Box the compass
You are encouraged to solve this task according to the task description, using any language you may know.
Avast me hearties!
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass!
Task description
- Create a function that takes a heading in degrees and returns the correct 32-point compass heading.
- Use the function to print and display a table of Index, Compass point, and Degree; rather like the corresponding columns from, the first table of the wikipedia article, but use only the following 33 headings as input:
[0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38]
. (They should give the same order of points but are spread throughout the ranges of acceptance).
Note
- The headings and indices can be calculated from this pseudocode:
for i in 0..32 inclusive: heading = i * 11.25 case i %3: if 1: heading += 5.62; break if 2: heading -= 5.62; break end index = ( i mod 32) + 1
ALGOL 68
<lang algol68>#!/usr/local/bin/a68g --script #
[]STRING
long by nesw = (" by ", "North", "East", "South", "West"), short by nesw = ("b", "N", "E", "S", "W");
MODE MINUTES = REAL; # minutes type # INT last minute=360*60; INT point width=last minute OVER 32;
PROC direction name = (REAL direction in minutes, []STRING locale directions)STRING: (
STRING by = locale directions[1]; []STRING nesw = locale directions[@-1];
PRIO MASK = 7; # same PRIOrity as * and / # OP MASK = (INT n, BITS lower)INT: ABS (BIN n AND NOT lower), DECAP = (STRING s)STRING: IF UPB s > 1 THEN REPR (ABS s[1]-ABS "A"+ABS "a")+s[2:] ELSE s FI;
PROC point name = (INT in point)STRING: (
INT point = in point MOD 32 # 32 points of a compass #; IF point MOD 8 = 0 THEN
- name the principle point: eg. N, E, S or W #
nesw[point OVER 8]
ELIF point MOD 4 = 0 THEN
- name the half: eg. NE, SE, SW or NW #
point name((point+8)MASK 2r1111)+DECAP point name(point MASK 2r1111 + 8)
ELIF point MOD 2 = 0 THEN
- name the quarter: eg. N-NE, E-NE, E-SE, S-SE, S-SW, W-SW, W-NW or N-NW #
point name((point+4)MASK 2r111)+"-"+point name(point MASK 2r111 + 4)
ELSE # Name the sixteenth point: #
- eg. NbE,NEbN,NEbE,EbN,EbS,SEbE,SEbS,SbE,SbW,SWbS,SWbW,WbS,WbN,NWbW,NWbN,NbW #
INT opp point = point OVER 8 + ABS NOT ODD (point OVER 2); point name((point+2)MASK 2r11)+ by +nesw(opp point MOD 4) FI ); point name(ROUND(direction in minutes/point width))
);
PROC traditional name = (MINUTES minutes)STRING: (
INT degrees = ROUND(minutes / 60); degrees=0 |"Tramontana" |: degrees=45 |"Greco or Bora" |: degrees=90 |"Levante" |: degrees=135|"Sirocco" |: degrees=180|"Ostro" |: degrees=225|"Libeccio" |: degrees=270|"Poniente or Zephyrus"|: degrees=315|"Mistral" |: degrees=360|"Tramontana" |""
);
- First generate the test set results #
test:(
printf($"Test:"l$); FOR i FROM 0 TO 32 DO REAL heading = i * 11.25 + CASE i MOD 3 IN +5.62, -5.62 OUT 0 ESAC; INT index = ( i MOD 32) + 1; printf(($zd" ", g23k, zzd.zzl$, index , direction name(heading*60, long by nesw), heading)) OD
);
table:(
OP OVER = (REAL r, INT base)INT: ENTIER ABS r OVER base, MOD = (REAL r, INT base)REAL: ( INT i = ENTIER r; i MOD base + r - i);
printf( $l"Table:"l " #|Compass point"22k"|Abbr|Traditional wind point| Lowest°′ | Middle°′ | Highest°′"l$ );
OP DEGMIN = (REAL minutes)STRUCT(INT d, REAL m): (minutes MOD last minute OVER 60, minutes MOD 60);
FOR point FROM 1 TO 32 DO REAL centre = (point-1) * point width; REAL from = centre - point width/2, to = centre + point width/2-1/120; printf(( $g(-2)"|"$, point, $g$, direction name(centre, long by nesw), $22k"|"g$, direction name(centre, short by nesw), $27k"|"g$, traditional name(centre), $50k$, $"|"g(-3)"°", dd.dd"′"$, DEGMIN from, DEGMIN centre, DEGMIN to, $l$ )) OD
)</lang> Output:
Test: 1 North 0.00 2 North by East 16.87 3 North-Northeast 16.88 4 Northeast by North 33.75 5 Northeast 50.62 6 Northeast by East 50.63 7 East-Northeast 67.50 8 East by North 84.37 9 East 84.38 10 East by South 101.25 11 East-Southeast 118.12 12 Southeast by East 118.13 13 Southeast 135.00 14 Southeast by South 151.87 15 South-Southeast 151.88 16 South by East 168.75 17 South 185.62 18 South by West 185.63 19 South-Southwest 202.50 20 Southwest by South 219.37 21 Southwest 219.38 22 Southwest by West 236.25 23 West-Southwest 253.12 24 West by South 253.13 25 West 270.00 26 West by North 286.87 27 West-Northwest 286.88 28 Northwest by West 303.75 29 Northwest 320.62 30 Northwest by North 320.63 31 North-Northwest 337.50 32 North by West 354.37 1 North 354.38 Table: #|Compass point |Abbr|Traditional wind point| Lowest°′ | Middle°′ | Highest°′ 1|North |N |Tramontana |354°22.50′| 0°00.00′| 5°37.49′ 2|North by East |NbE | | 5°37.50′| 11°15.00′| 16°52.49′ 3|North-Northeast |N-NE| | 16°52.50′| 22°30.00′| 28°07.49′ 4|Northeast by North|NEbN| | 28°07.50′| 33°45.00′| 39°22.49′ 5|Northeast |NE |Greco or Bora | 39°22.50′| 45°00.00′| 50°37.49′ 6|Northeast by East |NEbE| | 50°37.50′| 56°15.00′| 61°52.49′ 7|East-Northeast |E-NE| | 61°52.50′| 67°30.00′| 73°07.49′ 8|East by North |EbN | | 73°07.50′| 78°45.00′| 84°22.49′ 9|East |E |Levante | 84°22.50′| 90°00.00′| 95°37.49′ 10|East by South |EbS | | 95°37.50′|101°15.00′|106°52.49′ 11|East-Southeast |E-SE| |106°52.50′|112°30.00′|118°07.49′ 12|Southeast by East |SEbE| |118°07.50′|123°45.00′|129°22.49′ 13|Southeast |SE |Sirocco |129°22.50′|135°00.00′|140°37.49′ 14|Southeast by South|SEbS| |140°37.50′|146°15.00′|151°52.49′ 15|South-Southeast |S-SE| |151°52.50′|157°30.00′|163°07.49′ 16|South by East |SbE | |163°07.50′|168°45.00′|174°22.49′ 17|South |S |Ostro |174°22.50′|180°00.00′|185°37.49′ 18|South by West |SbW | |185°37.50′|191°15.00′|196°52.49′ 19|South-Southwest |S-SW| |196°52.50′|202°30.00′|208°07.49′ 20|Southwest by South|SWbS| |208°07.50′|213°45.00′|219°22.49′ 21|Southwest |SW |Libeccio |219°22.50′|225°00.00′|230°37.49′ 22|Southwest by West |SWbW| |230°37.50′|236°15.00′|241°52.49′ 23|West-Southwest |W-SW| |241°52.50′|247°30.00′|253°07.49′ 24|West by South |WbS | |253°07.50′|258°45.00′|264°22.49′ 25|West |W |Poniente or Zephyrus |264°22.50′|270°00.00′|275°37.49′ 26|West by North |WbN | |275°37.50′|281°15.00′|286°52.49′ 27|West-Northwest |W-NW| |286°52.50′|292°30.00′|298°07.49′ 28|Northwest by West |NWbW| |298°07.50′|303°45.00′|309°22.49′ 29|Northwest |NW |Mistral |309°22.50′|315°00.00′|320°37.49′ 30|Northwest by North|NWbN| |320°37.50′|326°15.00′|331°52.49′ 31|North-Northwest |N-NW| |331°52.50′|337°30.00′|343°07.49′ 32|North by West |NbW | |343°07.50′|348°45.00′|354°22.49′
C
<lang C>int main() {
int i, j; double degrees[] = { 0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38 }; char * names = "North " "North by east " "North-northeast " "Northeast by north " "Northeast " "Northeast by east " "East-northeast " "East by north " "East " "East by south " "East-southeast " "Southeast by east " "Southeast " "Southeast by south " "South-southeast " "South by east " "South " "South by west " "South-southwest " "Southwest by south " "Southwest " "Southwest by west " "West-southwest " "West by south " "West " "West by north " "West-northwest " "Northwest by west " "Northwest " "Northwest by north " "North-northwest " "North by west " "North ";
for (i = 0; i < 33; i++) { j = .5 + degrees[i] * 32 / 360;
printf("%2d %.22s %6.2f\n", i + 1, names + (j % 32) * 22, degrees[i]); }
return 0;
}</lang>Output:<lang>
1 North 0.00 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.50 8 East by north 84.37 9 East 84.38
10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135.00 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.50 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270.00 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.50 32 North by west 354.37 33 North 354.38 </lang>
C++
Using the Boost libraries
<lang cpp>#include <string>
- include <boost/array.hpp>
- include <boost/assign/list_of.hpp>
- include <boost/format.hpp>
- include <boost/foreach.hpp>
- include <iostream>
- include <math.h>
using std::string; using namespace boost::assign;
int get_Index(float angle) {
return static_cast<int>(floor(angle / 11.25 +0.5 )) % 32 + 1;
}
string get_Abbr_From_Index(int i) {
static boost::array<std::string, 32> points(list_of ("N")("NbE")("NNE")("NEbN")("NE")("NEbE")("ENE")("EbN") ("E")("EbS")("ESE")("SEbE")("SE")("SEbS")("SSE")("SbE") ("S")("SbW")("SSW")("SWbS")("SW")("SWbW")("WSW")("WbS") ("W")("WbN")("WNW")("NWbW")("NW")("NWbN")("NNW")("NbW")); return points[i-1];
}
string Build_Name_From_Abbreviation(string a) {
string retval; for (int i = 0; i < a.size(); ++i){ if ((1 == i) && (a[i] != 'b') && (a.size() == 3)) retval += "-"; switch (a[i]){ case 'N' : retval += "north"; break; case 'S' : retval += "south"; break; case 'E' : retval += "east"; break; case 'W' : retval += "west"; break; case 'b' : retval += " by "; break; } } retval[0] = toupper(retval[0]); return retval;
}
int main() {
boost::array<float,33> headings(list_of (0.0)(16.87)(16.88)(33.75)(50.62)(50.63)(67.5)(84.37)(84.38)(101.25) (118.12)(118.13)(135.0)(151.87)(151.88)(168.75)(185.62)(185.63)(202.5) (219.37)(219.38)(236.25)(253.12)(253.13)(270.0)(286.87)(286.88)(303.75) (320.62)(320.63)(337.5)(354.37)(354.38)); int i; boost::format f("%1$4d %2$-20s %3$_7.2f");
BOOST_FOREACH(float a, headings) { i = get_Index(a); std::cout << f % i % Build_Name_From_Abbreviation(get_Abbr_From_Index(i)) % a << std::endl; } return 0;
}</lang> Output:
1 North 0.00 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.50 8 East by north 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135.00 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.50 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270.00 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.50 32 North by west 354.37 1 North 354.38
Clojure
<lang lisp>(ns boxing-the-compass
(:use [clojure.string :only [capitalize]]))
(def headings
(for [i (range 0 (inc 32))] (let [heading (* i 11.25)]
(case (mod i 3) 1 (+ heading 5.62) 2 (- heading 5.62) heading))))
(defn angle2compass
[angle] (let [dirs ["N" "NbE" "N-NE" "NEbN" "NE" "NEbE" "E-NE" "EbN"
"E" "EbS" "E-SE" "SEbE" "SE" "SEbS" "S-SE" "SbE" "S" "SbW" "S-SW" "SWbS" "SW" "SWbW" "W-SW" "WbS" "W" "WbN" "W-NW" "NWbW" "NW" "NWbN" "N-NW" "NbW"] unpack {\N "north" \E "east" \W "west" \S "south" \b " by " \- "-"} sep (/ 360 (count dirs)) dir (int (/ (mod (+ angle (/ sep 2)) 360) sep))]
(capitalize (apply str (map unpack (dirs dir))))))
(apply str (map-indexed #(format "%2s %-18s %7.2f\n"
(inc (mod %1 32)) (angle2compass %2) %2) headings)))</lang> Output:
1 North 0.00 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.50 8 East by north 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135.00 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.50 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270.00 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.50 32 North by west 354.37 1 North 354.38
D
<lang d>import std.stdio, std.string, std.math, std.array;
struct boxTheCompass {
static string[32] points;
static this() { enum cardinal = ["north", "east", "south", "west"]; enum desc = ["1", "1 by 2", "1-C", "C by 1", "C", "C by 2", "2-C", "2 by 1"];
foreach (i; 0 .. 4) { auto s1 = cardinal[i]; auto s2 = cardinal[(i + 1) % 4]; auto sc = (s1 == "north" || s1 == "south") ? (s1 ~ s2) : (s2 ~ s1); foreach (j; 0 .. 8) points[i * 8 + j] = desc[j].replace("1", s1). replace("2", s2).replace("C",sc); } }
static string opCall(double degrees) { double testD = (degrees / 11.25) + 0.5; return capitalize(points[cast(int)floor(testD % 32)]); }
}
void main() {
foreach (i; 0 .. 33) { double heading = i * 11.25 + [0, 5.62, -5.62][i % 3]; writefln("%s\t%18s\t%s", i % 32 + 1, boxTheCompass(heading), heading); }
}</lang> Output:
1 North 0 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.5 8 East by north 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.5 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.5 32 North by west 354.37 1 North 354.38
Euphoria
<lang euphoria>constant names = {"North","North by east","North-northeast","Northeast by north",
"Northeast","Northeast by east","East-northeast","East by north","East", "East by south","East-southeast","Southeast by east","Southeast","Southeast by south", "South-southeast","South by east","South","South by west","South-southwest", "Southwest by south","Southwest","Southwest by west","West-southwest", "West by south","West","West by north","West-northwest","Northwest by west", "Northwest","Northwest by north","North-northwest","North by west"}
function deg2ind(atom degree)
return remainder(floor(degree*32/360+.5),32)+1
end function
sequence degrees degrees = {} for i = 0 to 32 do
degrees &= i*11.25 + 5.62*(remainder(i+1,3)-1)
end for
integer j for i = 1 to length(degrees) do
j = deg2ind(degrees[i]) printf(1, "%6.2f %2d %-22s\n", {degrees[i], j, names[j]})
end for</lang>
Output:
0.00 1 North 16.87 2 North by east 16.88 3 North-northeast 33.75 4 Northeast by north 50.62 5 Northeast 50.63 6 Northeast by east 67.50 7 East-northeast 84.37 8 East by north 84.38 9 East 101.25 10 East by south 118.12 11 East-southeast 118.13 12 Southeast by east 135.00 13 Southeast 151.87 14 Southeast by south 151.88 15 South-southeast 168.75 16 South by east 185.62 17 South 185.63 18 South by west 202.50 19 South-southwest 219.37 20 Southwest by south 219.38 21 Southwest 236.25 22 Southwest by west 253.12 23 West-southwest 253.13 24 West by south 270.00 25 West 286.87 26 West by north 286.88 27 West-northwest 303.75 28 Northwest by west 320.62 29 Northwest 320.63 30 Northwest by north 337.50 31 North-northwest 354.37 32 North by west 354.38 1 North
Fortran
<lang fortran>Program Compass
implicit none
integer :: i, ind real :: heading
do i = 0, 32 heading = i * 11.25 if (mod(i, 3) == 1) then heading = heading + 5.62 else if (mod(i, 3) == 2) then heading = heading - 5.62 end if ind = mod(i, 32) + 1 write(*, "(i2, a20, f8.2)") ind, compasspoint(heading), heading end do
contains
function compasspoint(h)
character(18) :: compasspoint character(18) :: points(32) = (/ "North ", "North by east ", "North-northeast ", & "Northeast by north", "Northeast ", "Northeast by east ", "East-northeast ", & "East by north ", "East ", "East by south ", "East-southeast ", & "Southeast by east ", "Southeast ", "Southeast by south", "South-southeast ", & "South by east ", "South ", "South by west ", "South-southwest ", & "Southwest by south", "Southwest ", "Southwest by west ", "West-southwest ", & "West by south ", "West ", "West by north ", "West-northwest ", & "Northwest by west ", "Northwest ", "Northwest by north", "North-northwest ", & "North by west " /) real, intent(in) :: h real :: x
x = h / 11.25 + 1.5 if (x >= 33.0) x = x - 32.0 compasspoint = points(int(x))
end function compasspoint end program Compass</lang> Output:
1 North 0.00 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.50 8 East by north 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135.00 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.50 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270.00 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.50 32 North by west 354.37 1 North 354.38
Go
<lang go>package main
import "fmt"
// function required by task func degrees2compasspoint(h float32) string {
return compassPoint[cpx(h)]
}
// cpx returns integer index from 0 to 31 corresponding to compass point. // input heading h is in degrees. Note this index is a zero-based index // suitable for indexing into the table of printable compass points, // and is not the same as the index specified to be printed in the output. func cpx(h float32) int {
x := int(h/11.25+.5) % 32 if x < 0 { x += 32 } return x
}
// printable compass points var compassPoint = []string{
"North", "North by east", "North-northeast", "Northeast by north", "Northeast", "Northeast by east", "East-northeast", "East by north", "East", "East by south", "East-southeast", "Southeast by east", "Southeast", "Southeast by south", "South-southeast", "South by east", "South", "South by west", "South-southwest", "Southwest by south", "Southwest", "Southwest by west", "West-southwest", "West by south", "West", "West by north", "West-northwest", "Northwest by west", "Northwest", "Northwest by north", "North-northwest", "North by west",
}
func main() {
fmt.Println("Index Compass point Degree") for i, h := range []float32{0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38} { index := i%32 + 1 // printable index computed per pseudocode fmt.Printf("%4d %-19s %7.2f°\n", index, degrees2compasspoint(h), h) }
}</lang>
Index Compass point Degree 1 North 0.00° 2 North by east 16.87° 3 North-northeast 16.88° 4 Northeast by north 33.75° 5 Northeast 50.62° 6 Northeast by east 50.63° 7 East-northeast 67.50° 8 East by north 84.37° 9 East 84.38° 10 East by south 101.25° 11 East-southeast 118.12° 12 Southeast by east 118.13° 13 Southeast 135.00° 14 Southeast by south 151.87° 15 South-southeast 151.88° 16 South by east 168.75° 17 South 185.62° 18 South by west 185.63° 19 South-southwest 202.50° 20 Southwest by south 219.37° 21 Southwest 219.38° 22 Southwest by west 236.25° 23 West-southwest 253.12° 24 West by south 253.13° 25 West 270.00° 26 West by north 286.87° 27 West-northwest 286.88° 28 Northwest by west 303.75° 29 Northwest 320.62° 30 Northwest by north 320.63° 31 North-northwest 337.50° 32 North by west 354.37° 1 North 354.38°
Haskell
<lang haskell> import Data.Char import Data.Maybe import Text.Printf
dirs = ["N", "NbE", "N-NE", "NEbN", "NE", "NEbE", "E-NE", "EbN",
"E", "EbS", "E-SE", "SEbE", "SE", "SEbS", "S-SE", "SbE", "S", "SbW", "S-SW", "SWbS", "SW", "SWbW", "W-SW", "WbS", "W", "WbN", "W-NW", "NWbW", "NW", "NWbN", "N-NW", "NbW"]
-- Given an index between 0 and 31 return the corresponding compass point name. pointName = capitalize . concatMap (fromMaybe "?" . fromChar) . (dirs !!)
where fromChar c = lookup c [('N', "north"), ('S', "south"), ('E', "east"), ('W', "west"), ('b', " by "), ('-', "-")] capitalize (c:cs) = toUpper c : cs
-- Convert degrees to a compass point index between 0 and 31. pointIndex d = (round (d*1000) + 5625) `mod` 360000 `div` 11250
printPointName d = let deg = read d :: Double
idx = pointIndex deg in printf "%2d %-18s %6.2f°\n" (idx+1) (pointName idx) deg
main = do
input <- getContents mapM_ printPointName $ lines input
</lang> Output:
1 North 0.00° 2 North by east 16.87° 3 North-northeast 16.88° 4 Northeast by north 33.75° 5 Northeast 50.62° 6 Northeast by east 50.63° 7 East-northeast 67.50° 8 East by north 84.37° 9 East 84.38° 10 East by south 101.25° 11 East-southeast 118.12° 12 Southeast by east 118.13° 13 Southeast 135.00° 14 Southeast by south 151.87° 15 South-southeast 151.88° 16 South by east 168.75° 17 South 185.62° 18 South by west 185.63° 19 South-southwest 202.50° 20 Southwest by south 219.37° 21 Southwest 219.38° 22 Southwest by west 236.25° 23 West-southwest 253.12° 24 West by south 253.13° 25 West 270.00° 26 West by north 286.87° 27 West-northwest 286.88° 28 Northwest by west 303.75° 29 Northwest 320.62° 30 Northwest by north 320.63° 31 North-northwest 337.50° 32 North by west 354.37° 1 North 354.38°
Icon and Unicon
<lang Icon>link strings,numbers
procedure main()
every heading := 11.25 * (i := 0 to 32) do {
case i%3 of { 1: heading +:= 5.62 2: heading -:= 5.62 } write(right(i+1,3)," ",left(direction(heading),20)," ",fix(heading,,7,2)) }
end
procedure direction(d) # compass heading given +/- degrees static dirs initial {
every put(dirs := [], replacem(!["N","NbE","N-NE","NEbN","NE","NEbE","E-NE","EbN", "E","EbS","E-SE","SEbE","SE","SEbS","S-SE","SbE",
"S","SbW","S-SW","SWbS","SW","SWbW","W-SW","WbS", "W","WbN","W-NW","NWbW","NW","NWbN","N-NW","NbW"],
"N","north","E","east","W","west","S","south","b"," by ")) } return dirs[round(((((d%360)+360)%360)/11.25)%32 + 1)]
end</lang>
strings for replacem numbers for round, fix
Output:
1 north 0.00 2 north by east 16.87 3 north-northeast 16.88 4 northeast by north 33.75 5 northeast 50.62 6 northeast by east 50.63 7 east-northeast 67.50 8 east by north 84.37 9 east 84.38 10 east by south 101.25 11 east-southeast 118.12 12 southeast by east 118.13 13 southeast 135.00 14 southeast by south 151.87 15 south-southeast 151.88 16 south by east 168.75 17 south 185.62 18 south by west 185.63 19 south-southwest 202.50 20 southwest by south 219.37 21 southwest 219.38 22 southwest by west 236.25 23 west-southwest 253.12 24 west by south 253.13 25 west 270.00 26 west by north 286.87 27 west-northwest 286.88 28 northwest by west 303.75 29 northwest 320.62 30 northwest by north 320.63 31 north-northwest 337.50 32 north by west 354.37
J
<lang j>require'strings' subs=: 'N,north,S,south,E,east,W,west,b, by ,' dirs=: subs (toupper@{., }.)@rplc~L:1 0&(<;._2) 0 :0 -. ' ',LF
N,NbE,N-NE,NEbN,NE,NEbE,E-NE,EbN,E,EbS,E-SE,SEbE,SE,SEbS,S-SE,SbE, S,SbW,S-SW,SWbS,SW,SWbW,W-SW,WbS,W,WbN,W-NW,NWbW,NW,NWbN,N-NW,NbW,
) indice=: 32 | 0.5 <.@+ %&11.25 deg2pnt=: dirs {~ indice</lang>
Example use:
<lang j> i.10 0 1 2 3 4 5 6 7 8 9
deg2pnt i.10
┌─────┬─────┬─────┬─────┬─────┬─────┬─────────────┬─────────────┬─────────────┬─────────────┐ │North│North│North│North│North│North│North by east│North by east│North by east│North by east│ └─────┴─────┴─────┴─────┴─────┴─────┴─────────────┴─────────────┴─────────────┴─────────────┘</lang>
Required example:
<lang j> (":@>:@indice,.' ',.>@deg2pnt,.' ',.":@,.)(*&11.25 + 5.62 * 0 1 _1 {~ 3&|) i.33 1 North 0 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.5 8 East by north 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.5 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.5 32 North by west 354.37 1 North 354.38</lang>
Java
<lang java>public class BoxingTheCompass{
private static String[] points = new String[32]; public static void main(String[] args){ buildPoints(); double heading = 0; for(int i = 0; i<= 32;i++){ heading = i * 11.25; switch(i % 3){ case 1: heading += 5.62; break; case 2: heading -= 5.62; break; default: } System.out.printf("%s\t%18s\t%s°\n",(i % 32) + 1, initialUpper(getPoint(heading)), heading); } } private static void buildPoints(){ String[] cardinal = {"north", "east", "south", "west"}; String[] pointDesc = {"1", "1 by 2", "1-C", "C by 1", "C", "C by 2", "2-C", "2 by 1"}; String str1, str2, strC; for(int i = 0;i <= 3;i++){ str1 = cardinal[i]; str2 = cardinal[(i + 1) % 4]; strC = (str1.equals("north") || str1.equals("south")) ? (str1 + str2): (str2 + str1); for(int j = 0;j <= 7;j++){ points[i * 8 + j] = pointDesc[j].replace("1", str1).replace("2", str2).replace("C", strC); } } } private static String initialUpper(String s){ return s.substring(0, 1).toUpperCase() + s.substring(1); } private static String getPoint(double degrees){ double testD = (degrees / 11.25) + 0.5; return points[(int)Math.floor(testD % 32)]; }
}</lang> Output:
1 North 0.0° 2 North by east 16.87° 3 North-northeast 16.88° 4 Northeast by north 33.75° 5 Northeast 50.62° 6 Northeast by east 50.63° 7 East-northeast 67.5° 8 East by north 84.37° 9 East 84.38° 10 East by south 101.25° 11 East-southeast 118.12° 12 Southeast by east 118.13° 13 Southeast 135.0° 14 Southeast by south 151.87° 15 South-southeast 151.88° 16 South by east 168.75° 17 South 185.62° 18 South by west 185.63° 19 South-southwest 202.5° 20 Southwest by south 219.37° 21 Southwest 219.38° 22 Southwest by west 236.25° 23 West-southwest 253.12° 24 West by south 253.13° 25 West 270.0° 26 West by north 286.87° 27 West-northwest 286.88° 28 Northwest by west 303.75° 29 Northwest 320.62° 30 Northwest by north 320.63° 31 North-northwest 337.5° 32 North by west 354.37° 1 North 354.38°
MUMPS
The TCL implementation was the starting point, but this isn't an exact translation. <lang MUMPS>BOXING(DEGREE)
;This takes in a degree heading, nominally from 0 to 360, and returns the compass point name. QUIT:((DEGREE<0)||(DEGREE>360)) "land lubber can't read a compass" NEW DIRS,UNP,UNPACK,SEP,DIR,DOS,D,DS,I,F SET DIRS="N^NbE^N-NE^NEbN^NE^NEbE^E-NE^EbN^E^EbS^E-SE^SEbE^SE^SEbS^S-SE^SbE^" SET DIRS=DIRS_"S^SbW^S-SW^SWbS^SW^SWbW^W-SW^WbS^W^WbN^W-NW^NWbW^NW^NWbN^N-NW^NbW" SET UNP="NESWb" SET UNPACK="north^east^south^west^ by " SET SEP=360/$LENGTH(DIRS,"^") SET DIR=(DEGREE/SEP)+1.5 SET DIR=$SELECT((DIR>33):DIR-32,1:DIR) SET DOS=$NUMBER(DIR-.5,0) SET D=$PIECE(DIRS,"^",DIR) SET DS="" FOR I=1:1:$LENGTH(D) DO . SET F=$FIND(UNP,$EXTRACT(D,I)) SET DS=DS_$SELECT((F>0):$PIECE(UNPACK,"^",F-1),1:$E(D,I)) KILL DIRS,UNP,UNPACK,SEP,DIR,D,I,F QUIT DOS_"^"_DS
BOXWRITE
NEW POINTS,UP,LO,DIR,P,X SET POINTS="0.0,16.87,16.88,33.75,50.62,50.63,67.5,84.37,84.38,101.25,118.12,118.13,135.0,151.87," SET POINTS=POINTS_"151.88,168.75,185.62,185.63,202.5,219.37,219.38,236.25,253.12,253.13,270.0,286.87," SET POINTS=POINTS_"286.88,303.75,320.62,320.63,337.5,354.37,354.38" SET UP="ABCDEFGHIJKLMNOPQRSTUVWXYZ" SET LO="abcdefghijklmnopqrstuvwxyz" FOR P=1:1:$LENGTH(POINTS,",") DO . SET X=$$BOXING($PIECE(POINTS,",",P)) . ;Capitalize the initial letter of the direction . SET DIR=$PIECE(X,"^",2) . SET DIR=$TRANSLATE($EXTRACT(DIR,1),LO,UP)_$EXTRACT(DIR,2,$LENGTH(DIR)) . WRITE $PIECE(X,"^"),?5,DIR,?40,$JUSTIFY($PIECE(POINTS,",",P),10,2),! KILL POINTS,UP,LO,DIR,P,X QUIT</lang>
Output:
Debugger executing 'BOXWRITE^COMPASS' 1 North 0.00 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.50 8 East by north 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135.00 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.50 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270.00 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.50 32 North by west 354.37 1 North 354.38
NetRexx
<lang NetRexx>/* NetRexx */ options replace format comments java crossref savelog symbols nobinary utf8
class RCBoxTheCompass
properties public constant
_FULL = '_FULL'
properties indirect
headings = Rexx rosepoints = Rexx
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method RCBoxTheCompass() public
setHeadings(makeHeadings) setRosepoints(makeRosepoints)
return
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method main(args = String[]) public static
box = RCBoxTheCompass()
cp = box.getCompassPoints loop r_ = 1 to cp[0] say cp[r_] end r_ say
hx = box.getHeadingsReport(box.getHeadings) loop r_ = 1 to hx[0] say hx[r_] end r_ say
return
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method getDecimalAngle(degrees, minutes, seconds) public static returns Rexx
degrees = degrees * 10 % 10 minutes = minutes * 10 % 10 angle = degrees + (minutes / 60 + (seconds / 60 / 60))
return angle
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method getDegreesMinutesSeconds(angle) public static returns Rexx
degrees = angle * 100 % 100 minutes = ((angle - degrees) * 60) * 100 % 100 seconds = ((((angle - degrees) * 60) - minutes) * 60) * 100 % 100
return degrees minutes seconds
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method getHeadingsReport(bearings) public returns Rexx
r_ = 0 table = r_ = r_ + 1; table[0] = r_; table[r_] = 'Idx' - 'Abbr' - 'Compass Point'.left(20) - 'Degrees'.right(10)
loop h_ = 1 to bearings[0] heading = bearings[h_] index = getRosepointIndex(heading) parse getRosepoint(index) p_abbrev p_full
r_ = r_ + 1; table[0] = r_; table[r_] = index.right(3) - p_abbrev.left(4) - p_full.left(20) - heading.format(6, 3).right(10) end h_
return table
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method getRosepointIndex(heading) public returns Rexx
one_pt = 360 / 32 hn = heading // 360 hi = hn % one_pt
if hn > hi * one_pt + one_pt / 2 then do hi = hi + 1 -- greater than max range for this point; bump to next point end
idx = hi // 32 + 1 -- add one to get index into rosepoints indexed string
return idx
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method getRosepoint(index) public returns Rexx
rp = getRosepoints return rp[index] rp[index, _FULL]
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method makeRosepoints() private returns Rexx
p_ = 0 rp = p_ = p_ + 1; rp[0] = p_; rp[p_] = 'N'; rp[p_, _FULL] = 'North' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NbE'; rp[p_, _FULL] = 'North by East' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NNE'; rp[p_, _FULL] = 'North-Northeast' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NEbn'; rp[p_, _FULL] = 'Northeast by North' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NE'; rp[p_, _FULL] = 'Northeast' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NEbE'; rp[p_, _FULL] = 'Northeast by East' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'ENE'; rp[p_, _FULL] = 'East-Northeast' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'EbN'; rp[p_, _FULL] = 'East by North' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'E'; rp[p_, _FULL] = 'East' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'EbS'; rp[p_, _FULL] = 'East by South' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'ESE'; rp[p_, _FULL] = 'East-Southeast' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SEbE'; rp[p_, _FULL] = 'Southeast by East' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SE'; rp[p_, _FULL] = 'Southeast' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SEbS'; rp[p_, _FULL] = 'Southeast by South' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SSE'; rp[p_, _FULL] = 'South-Southeast' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SbE'; rp[p_, _FULL] = 'South by East' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'S'; rp[p_, _FULL] = 'South' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SbW'; rp[p_, _FULL] = 'South by West' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SSW'; rp[p_, _FULL] = 'South-Southwest' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SWbS'; rp[p_, _FULL] = 'Southwest by South' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SW'; rp[p_, _FULL] = 'Southwest' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'SWbW'; rp[p_, _FULL] = 'Southwest by West' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'WSW'; rp[p_, _FULL] = 'Southwest' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'WbS'; rp[p_, _FULL] = 'West by South' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'W'; rp[p_, _FULL] = 'West' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'WbN'; rp[p_, _FULL] = 'West by North' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'WNW'; rp[p_, _FULL] = 'West-Northwest' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NWbW'; rp[p_, _FULL] = 'Northwest by West' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NW'; rp[p_, _FULL] = 'Northwest' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NWbN'; rp[p_, _FULL] = 'Northwest by North' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NNW'; rp[p_, _FULL] = 'North-Northwest' p_ = p_ + 1; rp[0] = p_; rp[p_] = 'NbW'; rp[p_, _FULL] = 'North by West'
return rp
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method makeHeadings() private returns Rexx
hdg = hdg[0] = 0 points = 32 loop i_ = 0 to points heading = i_ * 360 / points
select case i_ // 3 when 1 then heading_h = heading + 5.62 when 2 then heading_h = heading - 5.62 otherwise heading_h = heading end
ix = hdg[0] + 1; hdg[0] = ix; hdg[ix] = heading_h end i_
return hdg
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ method getCompassPoints() public returns Rexx
r_ = 0 table = r_ = r_ + 1; table[0] = r_; table[r_] = 'Idx' - 'Abbr' - 'Compass Point'.left(20) - 'Low (Deg.)'.right(10) - 'Mid (Deg.)'.right(10) - 'Hi (Deg.)'.right(10)
-- one point of the compass is 360 / 32 (11.25) degrees -- using functions to calculate this just for fun one_pt = 360 / 32 parse getDegreesMinutesSeconds(one_pt / 2) ad am as . points = 32 loop h_ = 0 to points - 1 heading = h_ * 360 / points hmin = heading - getDecimalAngle(ad, am, as) hmax = heading + getDecimalAngle(ad, am, as)
if hmin < 0 then do hmin = hmin + 360 end if hmax >= 360 then do hmax = hmax - 360 end
index = getRosepointIndex(heading) parse getRosepoint(index) p_abbrev p_full r_ = r_ + 1; table[0] = r_; table[r_] = index.right(3) - p_abbrev.left(4) - p_full.left(20) - hmin.format(6, 3).right(10) - heading.format(6, 3).right(10) - hmax.format(6, 3).right(10) end h_
return table
</lang>
- Output
Idx Abbr Compass Point Low (Deg.) Mid (Deg.) Hi (Deg.) 1 N North 354.375 0.000 5.625 2 NbE North by East 5.625 11.250 16.875 3 NNE North-Northeast 16.875 22.500 28.125 4 NEbn Northeast by North 28.125 33.750 39.375 5 NE Northeast 39.375 45.000 50.625 6 NEbE Northeast by East 50.625 56.250 61.875 7 ENE East-Northeast 61.875 67.500 73.125 8 EbN East by North 73.125 78.750 84.375 9 E East 84.375 90.000 95.625 10 EbS East by South 95.625 101.250 106.875 11 ESE East-Southeast 106.875 112.500 118.125 12 SEbE Southeast by East 118.125 123.750 129.375 13 SE Southeast 129.375 135.000 140.625 14 SEbS Southeast by South 140.625 146.250 151.875 15 SSE South-Southeast 151.875 157.500 163.125 16 SbE South by East 163.125 168.750 174.375 17 S South 174.375 180.000 185.625 18 SbW South by West 185.625 191.250 196.875 19 SSW South-Southwest 196.875 202.500 208.125 20 SWbS Southwest by South 208.125 213.750 219.375 21 SW Southwest 219.375 225.000 230.625 22 SWbW Southwest by West 230.625 236.250 241.875 23 WSW Southwest 241.875 247.500 253.125 24 WbS West by South 253.125 258.750 264.375 25 W West 264.375 270.000 275.625 26 WbN West by North 275.625 281.250 286.875 27 WNW West-Northwest 286.875 292.500 298.125 28 NWbW Northwest by West 298.125 303.750 309.375 29 NW Northwest 309.375 315.000 320.625 30 NWbN Northwest by North 320.625 326.250 331.875 31 NNW North-Northwest 331.875 337.500 343.125 32 NbW North by West 343.125 348.750 354.375 Idx Abbr Compass Point Degrees 1 N North 0.000 2 NbE North by East 16.870 3 NNE North-Northeast 16.880 4 NEbn Northeast by North 33.750 5 NE Northeast 50.620 6 NEbE Northeast by East 50.630 7 ENE East-Northeast 67.500 8 EbN East by North 84.370 9 E East 84.380 10 EbS East by South 101.250 11 ESE East-Southeast 118.120 12 SEbE Southeast by East 118.130 13 SE Southeast 135.000 14 SEbS Southeast by South 151.870 15 SSE South-Southeast 151.880 16 SbE South by East 168.750 17 S South 185.620 18 SbW South by West 185.630 19 SSW South-Southwest 202.500 20 SWbS Southwest by South 219.370 21 SW Southwest 219.380 22 SWbW Southwest by West 236.250 23 WSW Southwest 253.120 24 WbS West by South 253.130 25 W West 270.000 26 WbN West by North 286.870 27 WNW West-Northwest 286.880 28 NWbW Northwest by West 303.750 29 NW Northwest 320.620 30 NWbN Northwest by North 320.630 31 NNW North-Northwest 337.500 32 NbW North by West 354.370 1 N North 354.380
Perl
Don't waste brain cells calculating names, not worth the effort. Code is probably shorter, faster, and easier to read this way. <lang Perl>use utf8;
my @names = ( "North", "North by east", "North-northeast", "Northeast by north", "Northeast", "Northeast by east", "East-northeast", "East by north", "East", "East by south", "East-southeast", "Southeast by east", "Southeast", "Southeast by south", "South-southeast", "South by east", "South", "South by west", "South-southwest", "Southwest by south", "Southwest", "Southwest by west", "West-southwest", "West by south", "West", "West by north", "West-northwest", "Northwest by west", "Northwest", "Northwest by north", "North-northwest", "North by west", ); my @angles = (0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38);
for (@angles) { my $i = int(($_ * 32 / 360) + .5) % 32; printf "%3d %18s %6.2f°\n", $i + 1, $names[$i], $_; }</lang>output<lang> 1 North 0.00°
2 North by east 16.87° 3 North-northeast 16.88° 4 Northeast by north 33.75° 5 Northeast 50.62° 6 Northeast by east 50.63° 7 East-northeast 67.50° 8 East by north 84.37° 9 East 84.38° 10 East by south 101.25° 11 East-southeast 118.12° 12 Southeast by east 118.13° 13 Southeast 135.00° 14 Southeast by south 151.87° 15 South-southeast 151.88° 16 South by east 168.75° 17 South 185.62° 18 South by west 185.63° 19 South-southwest 202.50° 20 Southwest by south 219.37° 21 Southwest 219.38° 22 Southwest by west 236.25° 23 West-southwest 253.12° 24 West by south 253.13° 25 West 270.00° 26 West by north 286.87° 27 West-northwest 286.88° 28 Northwest by west 303.75° 29 Northwest 320.62° 30 Northwest by north 320.63° 31 North-northwest 337.50° 32 North by west 354.37° 1 North 354.38°</lang>
Perl 6
<lang perl6>sub point (Int $index) {
my $ix = $index % 32; if $ix +& 1 { "&point(($ix + 1) +& 28) by &point(((2 - ($ix +& 2)) * 4) + $ix +& 24)" } elsif $ix +& 2 { "&point(($ix + 2) +& 24)-&point(($ix +| 4) +& 28)" } elsif $ix +& 4 { "&point(($ix + 8) +& 16)&point(($ix +| 8) +& 24)" } else { <north east south west>[$ix div 8]; }
}
sub test-angle ($ix) { $ix * 11.25 + (0, 5.62, -5.62)[ $ix % 3 ] } sub angle-to-point($𝜽) { floor $𝜽 / 360 * 32 + 0.5 }
for 0 .. 32 -> $ix {
my $𝜽 = test-angle($ix); printf " %2d %6.2f%s %s\n", $ix % 32 + 1, $𝜽, '°', ucfirst point angle-to-point $𝜽;
}</lang>
Output:
1 0.00° North 2 16.87° North by east 3 16.88° North-northeast 4 33.75° Northeast by north 5 50.62° Northeast 6 50.63° Northeast by east 7 67.50° East-northeast 8 84.37° East by north 9 84.38° East 10 101.25° East by south 11 118.12° East-southeast 12 118.13° Southeast by east 13 135.00° Southeast 14 151.87° Southeast by south 15 151.88° South-southeast 16 168.75° South by east 17 185.62° South 18 185.63° South by west 19 202.50° South-southwest 20 219.37° Southwest by south 21 219.38° Southwest 22 236.25° Southwest by west 23 253.12° West-southwest 24 253.13° West by south 25 270.00° West 26 286.87° West by north 27 286.88° West-northwest 28 303.75° Northwest by west 29 320.62° Northwest 30 320.63° Northwest by north 31 337.50° North-northwest 32 354.37° North by west 1 354.38° North
PicoLisp
<lang PicoLisp>(scl 3)
(setq *Compass # Build lookup table
(let H -16.875 (mapcar '((Str) (cons (inc 'H 11.25) # Heading in degrees (pack # Compass point (replace (chop Str) "N" "north" "E" "east" "S" "south" "W" "west" "b" " by " ) ) ) ) '("N" "NbE" "N-NE" "NEbN" "NE" "NEbE" "E-NE" "EbN" "E" "EbS" "E-SE" "SEbE" "SE" "SEbS" "S-SE" "SbE" "S" "SbW" "S-SW" "SWbS" "SW" "SWbW" "W-SW" "WbS" "W" "WbN" "W-NW" "NWbW" "NW" "NWbN" "N-NW" "NbW" "N" ) ) ) )
(de heading (Deg)
(rank (% Deg 360.00) *Compass) )
(for I (range 0 32)
(let H (* I 11.25) (case (% I 3) (1 (inc 'H 5.62)) (2 (dec 'H 5.62)) ) (tab (3 1 -18 8) (inc (% I 32)) NIL (cdr (heading H)) (round H 2) ) ) )</lang>
Output:
1 north 0.00 2 north by east 16.87 3 north-northeast 16.88 4 northeast by north 33.75 5 northeast 50.62 6 northeast by east 50.63 7 east-northeast 67.50 8 east by north 84.37 9 east 84.38 10 east by south 101.25 11 east-southeast 118.12 12 southeast by east 118.13 13 southeast 135.00 14 southeast by south 151.87 15 south-southeast 151.88 16 south by east 168.75 17 south 185.62 18 south by west 185.63 19 south-southwest 202.50 20 southwest by south 219.37 21 southwest 219.38 22 southwest by west 236.25 23 west-southwest 253.12 24 west by south 253.13 25 west 270.00 26 west by north 286.87 27 west-northwest 286.88 28 northwest by west 303.75 29 northwest 320.62 30 northwest by north 320.63 31 north-northwest 337.50 32 north by west 354.37 1 north 354.38
PureBasic
<lang PureBasic>DataSection
Data.s "N", "north", "E", "east", "W", "west", "S", "south", "b", " by " ;abbreviations, expansions Data.s "N NbE N-NE NEbN NE NEbE E-NE EbN E EbS E-SE SEbE SE SEbS S-SE SbE" ;dirs Data.s "S SbW S-SW SWbS SW SWbW W-SW WbS W WbN W-NW NWbW NW NWbN N-NW NbW"
EndDataSection
- initialize data
NewMap dirSubst.s() Define i, abbr.s, expansion.s For i = 1 To 5
Read.s abbr Read.s expansion dirSubst(abbr) = expansion
Next
Dim dirs.s(32) Define j, s.s For j = 0 To 1
Read.s s.s For i = 0 To 15 abbr.s = StringField(s, i + 1, " ") dirs(j * 16 + i) = abbr Next
Next
- expand abbreviated compass point and capitalize
Procedure.s abbr2compassPoint(abbr.s)
Shared dirSubst() Protected i, compassPoint.s, key.s For i = 1 To Len(abbr) key.s = Mid(abbr, i, 1) If FindMapElement(dirSubst(), key) compassPoint + dirSubst(key) Else compassPoint + key EndIf Next ProcedureReturn UCase(Left(compassPoint, 1)) + Mid(compassPoint, 2)
EndProcedure
Procedure.s angle2compass(angle.f)
Shared dirs() Static segment.f = 360.0 / 32 ;width of each compass segment Protected dir ;work out which segment contains the compass angle dir = Int((Mod(angle, 360) / segment) + 0.5) ;convert to a named direction ProcedureReturn abbr2compassPoint(dirs(dir))
EndProcedure
- box the compass
If OpenConsole()
Define i, heading.f, index For i = 0 To 32 heading = i * 11.25 If i % 3 = 1 heading + 5.62 EndIf If i % 3 = 2 heading - 5.62 EndIf index = i % 32 + 1 PrintN(RSet(Str(index), 2) + " " + LSet(angle2compass(heading), 18) + RSet(StrF(heading, 2), 7)) Next Print(#CRLF$ + #CRLF$ + "Press ENTER to exit"): Input() CloseConsole()
EndIf</lang> Sample output:
1 North 0.00 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.50 8 East by north 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135.00 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.50 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270.00 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.50 32 North by west 354.37 1 354.38
Prolog
Part 1 : The following knowledge base takes a heading in degrees and returns the correct 32-point compass heading. It can also go in the other direction. <lang prolog> compassangle(1, 'North',n, 0.00). compassangle(2, 'North by east', nbe, 11.25). compassangle(3, 'North-northeast', nne,22.50). compassangle(4, 'Northeast by north', nebn,33.75). compassangle(5, 'Northeast', ne,45.00). compassangle(6, 'Norteast by east', nebe,56.25). compassangle(7, 'East-northeast', ene,67.50). compassangle(8, 'East by North', ebn,78.75). compassangle(9, 'East', e,90.00). compassangle(10, 'East by south', ebs, 101.25). compassangle(11, 'East-southeast', ese,112.50). compassangle(12, 'Southeast by east', sebe, 123.75). compassangle(13, 'Southeast', se, 135.00). compassangle(14, 'Southeast by south', sebs, 146.25). compassangle(15, 'South-southeast',sse, 157.50). compassangle(16, 'South by east', sbe, 168.75). compassangle(17, 'South', s, 180.00). compassangle(18, 'South by west', sbw, 191.25). compassangle(19, 'South-southwest', ssw, 202.50). compassangle(20, 'Southwest by south', swbs, 213.75). compassangle(21, 'Southwest', sw, 225.00). compassangle(22, 'Southwest by west', swbw, 236.25). compassangle(23, 'West-southwest', wsw, 247.50). compassangle(24, 'West by south', wbs, 258.75). compassangle(25, 'West', w, 270.00). compassangle(26, 'West by north', wbn, 281.25). compassangle(27, 'West-northwest', wnw, 292.50). compassangle(28, 'Northwest by west', nwbw, 303.75). compassangle(29, 'Northwest', nw, 315.00). compassangle(30, 'Northwest by north', nwbn, 326.25). compassangle(31, 'North-northwest', nnw, 337.50). compassangle(32, 'North by west', nbw, 348.75). compassangle(1, 'North', n, 360.00). compassangle(Index , Name, Heading, Angle) :- nonvar(Angle), resolveindex(Angle, Index),
compassangle(Index,Name, Heading, _).
resolveindex(Angle, Index) :- N is Angle / 11.25 + 0.5, I is floor(N),Index is (I mod 32) + 1. </lang> Part 2 : The following rules print a table of indexes. <lang prolog> printTableRow(Angle) :- compassangle(Index, Name, _, Angle),
write(Index), write(' '), write(Name), write(' '), write(Angle).
printTable([X|Xs]) :- printTableRow(X), nl, printTable(Xs),!. printTable([]). </lang> The following query prints the required table. <lang prolog> ?- printTable([0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62,
185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38]).
1 North 0.0 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Norteast by east 50.63 7 East-northeast 67.5 8 East by North 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135.0 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.5 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270.0 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.5 32 North by west 354.37 1 North 354.38 true. </lang>
Python
<lang python>majors = 'north east south west'.split() majors *= 2 # no need for modulo later quarter1 = 'N,N by E,N-NE,NE by N,NE,NE by E,E-NE,E by N'.split(',') quarter2 = [p.replace('NE','EN') for p in quarter1]
def degrees2compasspoint(d):
d = (d % 360) + 360/64 majorindex, minor = divmod(d, 90.) majorindex = int(majorindex) minorindex = int( (minor*4) // 45 ) p1, p2 = majors[majorindex: majorindex+2] if p1 in {'north', 'south'}: q = quarter1 else: q = quarter2 return q[minorindex].replace('N', p1).replace('E', p2).capitalize()
if __name__ == '__main__':
for i in range(33): d = i * 11.25 m = i % 3 if m == 1: d += 5.62 elif m == 2: d -= 5.62 n = i % 32 + 1 print( '%2i %-18s %7.2f°' % (n, degrees2compasspoint(d), d) )</lang>
- Output
1 North 0.00° 2 North by east 16.87° 3 North-northeast 16.88° 4 Northeast by north 33.75° 5 Northeast 50.62° 6 Northeast by east 50.63° 7 East-northeast 67.50° 8 East by north 84.37° 9 East 84.38° 10 East by south 101.25° 11 East-southeast 118.12° 12 Southeast by east 118.13° 13 Southeast 135.00° 14 Southeast by south 151.87° 15 South-southeast 151.88° 16 South by east 168.75° 17 South 185.62° 18 South by west 185.63° 19 South-southwest 202.50° 20 Southwest by south 219.37° 21 Southwest 219.38° 22 Southwest by west 236.25° 23 West-southwest 253.12° 24 West by south 253.13° 25 West 270.00° 26 West by north 286.87° 27 West-northwest 286.88° 28 Northwest by west 303.75° 29 Northwest 320.62° 30 Northwest by north 320.63° 31 North-northwest 337.50° 32 North by west 354.37° 1 North 354.38°
REXX
This example is written in ooRexx <lang REXX>/* Rexx */
Do
globs = '!DEG !MIN !SEC !FULL' Drop !DEG !MIN !SEC !FULL sign. = sign.!DEG = 'c2b0'x -- degree sign : U+00B0 sign.!MIN = 'e280b2'x -- prime : U+2032 sign.!SEC = 'e280b3'x -- double prime : U+2033 points. =
Call display_compass_points
Call display_sample Say
headings. = headings.0 = 0 Call make_headings
Call flush_queue Do h_ = 1 to headings.0 Queue headings.h_ End h_
Call display_sample Say
Return
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ flush_queue: Procedure Do
Do q_ = 1 to queued() Parse pull . End q_ Return
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ display_sample: Procedure Expose points. sign. (globs) Do
Do q_ = 1 to queued() Parse pull heading index = get_index(heading) Parse Value get_point(index) with p_abbrev p_full Say index~right(3), p_abbrev~left(4) p_full~left(20), heading~format(5, 3) || sign.!DEG '('format_degrees_minutes_seconds(heading)')', End q_
Return
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ display_compass_points: Procedure Expose points. sign. (globs) Do
points = 32 one_pt = 360 / points
Do h_ = 0 to points - 1 heading = h_ * 360 / points hmin = heading - one_pt / 2 hmax = heading + one_pt / 2
If hmin < 0 then Do hmin = hmin + 360 End If hmax >= 360 then Do hmax = hmax - 360 End
index = (h_ // points) + 1 Parse Value get_point(index) with p_abbrev p_full
Say index~right(3), p_abbrev~left(4) p_full~left(20), hmin~format(5, 3) || sign.!DEG '('format_degrees_minutes_seconds(hmin)')', heading~format(5, 3) || sign.!DEG '('format_degrees_minutes_seconds(heading)')', hmax~format(5, 3) || sign.!DEG '('format_degrees_minutes_seconds(hmax)')', End h_ Say
Return
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ make_headings: Procedure Expose headings. Do
points = 32 Do i_ = 0 to points heading = i_ * 360 / 32
it = i_ // 3 Select When it = 1 then Do heading_h = heading + 5.62 End
When it = 2 then Do heading_h = heading - 5.62 End
Otherwise Do heading_h = heading End End
index = (i_ // points) + 1 ix = headings.0 + 1; headings.0 = ix; headings.ix = heading_h End i_
Return
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ get_index: Procedure Do
Parse Arg heading .
one_pt = 360 / 32 hn = heading // 360 hi = hn % one_pt
If hn > hi * one_pt + one_pt / 2 then Do hi = hi + 1 -- greater than max range for this point; bump to next point End
idx = hi // 32 + 1 -- add one to get index into points. stem
Return idx
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ get_point: Procedure Expose points. sign. (globs) Do
Parse arg index .
Call get_points
Return points.index points.index.!FULL
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ get_points: Procedure Expose points. sign. (globs) Do
Drop !FULL
points. = p_ = 0 p_ = p_ + 1; points.0 = p_; points.p_ = 'N'; points.p_.!FULL = 'North' p_ = p_ + 1; points.0 = p_; points.p_ = 'NbE'; points.p_.!FULL = 'North by East' p_ = p_ + 1; points.0 = p_; points.p_ = 'NNE'; points.p_.!FULL = 'North-Northeast' p_ = p_ + 1; points.0 = p_; points.p_ = 'NEbn'; points.p_.!FULL = 'Northeast by North' p_ = p_ + 1; points.0 = p_; points.p_ = 'NE'; points.p_.!FULL = 'Northeast' p_ = p_ + 1; points.0 = p_; points.p_ = 'NEbE'; points.p_.!FULL = 'Northeast by East' p_ = p_ + 1; points.0 = p_; points.p_ = 'ENE'; points.p_.!FULL = 'East-Northeast' p_ = p_ + 1; points.0 = p_; points.p_ = 'EbN'; points.p_.!FULL = 'East by North' p_ = p_ + 1; points.0 = p_; points.p_ = 'E'; points.p_.!FULL = 'East' p_ = p_ + 1; points.0 = p_; points.p_ = 'EbS'; points.p_.!FULL = 'East by South' p_ = p_ + 1; points.0 = p_; points.p_ = 'ESE'; points.p_.!FULL = 'East-Southeast' p_ = p_ + 1; points.0 = p_; points.p_ = 'SEbE'; points.p_.!FULL = 'Southeast by East' p_ = p_ + 1; points.0 = p_; points.p_ = 'SE'; points.p_.!FULL = 'Southeast' p_ = p_ + 1; points.0 = p_; points.p_ = 'SEbS'; points.p_.!FULL = 'Southeast by South' p_ = p_ + 1; points.0 = p_; points.p_ = 'SSE'; points.p_.!FULL = 'South-Southeast' p_ = p_ + 1; points.0 = p_; points.p_ = 'SbE'; points.p_.!FULL = 'South by East' p_ = p_ + 1; points.0 = p_; points.p_ = 'S'; points.p_.!FULL = 'South' p_ = p_ + 1; points.0 = p_; points.p_ = 'SbW'; points.p_.!FULL = 'South by West' p_ = p_ + 1; points.0 = p_; points.p_ = 'SSW'; points.p_.!FULL = 'South-Southwest' p_ = p_ + 1; points.0 = p_; points.p_ = 'SWbS'; points.p_.!FULL = 'Southwest by South' p_ = p_ + 1; points.0 = p_; points.p_ = 'SW'; points.p_.!FULL = 'Southwest' p_ = p_ + 1; points.0 = p_; points.p_ = 'SWbW'; points.p_.!FULL = 'Southwest by West' p_ = p_ + 1; points.0 = p_; points.p_ = 'WSW'; points.p_.!FULL = 'Southwest' p_ = p_ + 1; points.0 = p_; points.p_ = 'WbS'; points.p_.!FULL = 'West by South' p_ = p_ + 1; points.0 = p_; points.p_ = 'W'; points.p_.!FULL = 'West' p_ = p_ + 1; points.0 = p_; points.p_ = 'WbN'; points.p_.!FULL = 'West by North' p_ = p_ + 1; points.0 = p_; points.p_ = 'WNW'; points.p_.!FULL = 'West-Northwest' p_ = p_ + 1; points.0 = p_; points.p_ = 'NWbW'; points.p_.!FULL = 'Northwest by West' p_ = p_ + 1; points.0 = p_; points.p_ = 'NW'; points.p_.!FULL = 'Northwest' p_ = p_ + 1; points.0 = p_; points.p_ = 'NWbN'; points.p_.!FULL = 'Northwest by North' p_ = p_ + 1; points.0 = p_; points.p_ = 'NNW'; points.p_.!FULL = 'North-Northwest' p_ = p_ + 1; points.0 = p_; points.p_ = 'NbW'; points.p_.!FULL = 'North by West'
Return
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ get_decimal_angle: Procedure Expose sign. (globs) Do
Parse Arg degrees ., minutes ., seconds .
degrees = degrees * 10 % 10 minutes = minutes * 10 % 10
angle = degrees + minutes / 60 + seconds / 60 / 60
Return angle
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ format_decimal_angle: Procedure Expose sign. (globs) Do
Parse Arg degrees ., minutes ., seconds .
Return get_decimal_angle(degrees, minutes, seconds)~format(5, 3) || sign.!DEG
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ get_degrees_minutes_seconds: Procedure Expose sign. (globs) Do
Parse arg angle .
degrees = angle * 100 % 100 minutes = ((angle - degrees) * 60) * 100 % 100 seconds = ((((angle - degrees) * 60) - minutes) * 60) * 100 % 100
Return degrees minutes seconds
End Exit
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ format_degrees_minutes_seconds: Procedure Expose sign. (globs) Do
Parse arg angle .
Parse Value get_degrees_minutes_seconds(angle) with degrees minutes seconds .
formatted = degrees~right(3) || sign.!DEG || minutes~right(2, 0) || sign.!MIN || seconds~right(2, 0) || sign.!SEC
Return formatted
End Exit </lang>
- Output
1 N North 354.375° (354°22′30″) 0.000° ( 0°00′00″) 5.625° ( 5°37′30″) 2 NbE North by East 5.625° ( 5°37′30″) 11.250° ( 11°15′00″) 16.875° ( 16°52′30″) 3 NNE North-Northeast 16.875° ( 16°52′30″) 22.500° ( 22°30′00″) 28.125° ( 28°07′30″) 4 NEbn Northeast by North 28.125° ( 28°07′30″) 33.750° ( 33°45′00″) 39.375° ( 39°22′30″) 5 NE Northeast 39.375° ( 39°22′30″) 45.000° ( 45°00′00″) 50.625° ( 50°37′30″) 6 NEbE Northeast by East 50.625° ( 50°37′30″) 56.250° ( 56°15′00″) 61.875° ( 61°52′30″) 7 ENE East-Northeast 61.875° ( 61°52′30″) 67.500° ( 67°30′00″) 73.125° ( 73°07′30″) 8 EbN East by North 73.125° ( 73°07′30″) 78.750° ( 78°45′00″) 84.375° ( 84°22′30″) 9 E East 84.375° ( 84°22′30″) 90.000° ( 90°00′00″) 95.625° ( 95°37′30″) 10 EbS East by South 95.625° ( 95°37′30″) 101.250° (101°15′00″) 106.875° (106°52′30″) 11 ESE East-Southeast 106.875° (106°52′30″) 112.500° (112°30′00″) 118.125° (118°07′30″) 12 SEbE Southeast by East 118.125° (118°07′30″) 123.750° (123°45′00″) 129.375° (129°22′30″) 13 SE Southeast 129.375° (129°22′30″) 135.000° (135°00′00″) 140.625° (140°37′30″) 14 SEbS Southeast by South 140.625° (140°37′30″) 146.250° (146°15′00″) 151.875° (151°52′30″) 15 SSE South-Southeast 151.875° (151°52′30″) 157.500° (157°30′00″) 163.125° (163°07′30″) 16 SbE South by East 163.125° (163°07′30″) 168.750° (168°45′00″) 174.375° (174°22′30″) 17 S South 174.375° (174°22′30″) 180.000° (180°00′00″) 185.625° (185°37′30″) 18 SbW South by West 185.625° (185°37′30″) 191.250° (191°15′00″) 196.875° (196°52′30″) 19 SSW South-Southwest 196.875° (196°52′30″) 202.500° (202°30′00″) 208.125° (208°07′30″) 20 SWbS Southwest by South 208.125° (208°07′30″) 213.750° (213°45′00″) 219.375° (219°22′30″) 21 SW Southwest 219.375° (219°22′30″) 225.000° (225°00′00″) 230.625° (230°37′30″) 22 SWbW Southwest by West 230.625° (230°37′30″) 236.250° (236°15′00″) 241.875° (241°52′30″) 23 WSW Southwest 241.875° (241°52′30″) 247.500° (247°30′00″) 253.125° (253°07′30″) 24 WbS West by South 253.125° (253°07′30″) 258.750° (258°45′00″) 264.375° (264°22′30″) 25 W West 264.375° (264°22′30″) 270.000° (270°00′00″) 275.625° (275°37′30″) 26 WbN West by North 275.625° (275°37′30″) 281.250° (281°15′00″) 286.875° (286°52′30″) 27 WNW West-Northwest 286.875° (286°52′30″) 292.500° (292°30′00″) 298.125° (298°07′30″) 28 NWbW Northwest by West 298.125° (298°07′30″) 303.750° (303°45′00″) 309.375° (309°22′30″) 29 NW Northwest 309.375° (309°22′30″) 315.000° (315°00′00″) 320.625° (320°37′30″) 30 NWbN Northwest by North 320.625° (320°37′30″) 326.250° (326°15′00″) 331.875° (331°52′30″) 31 NNW North-Northwest 331.875° (331°52′30″) 337.500° (337°30′00″) 343.125° (343°07′30″) 32 NbW North by West 343.125° (343°07′30″) 348.750° (348°45′00″) 354.375° (354°22′30″) 1 N North 0.000° ( 0°00′00″) 2 NbE North by East 16.870° ( 16°52′12″) 3 NNE North-Northeast 16.880° ( 16°52′48″) 4 NEbn Northeast by North 33.750° ( 33°45′00″) 5 NE Northeast 50.620° ( 50°37′12″) 6 NEbE Northeast by East 50.630° ( 50°37′48″) 7 ENE East-Northeast 67.500° ( 67°30′00″) 8 EbN East by North 84.370° ( 84°22′12″) 9 E East 84.380° ( 84°22′48″) 10 EbS East by South 101.250° (101°15′00″) 11 ESE East-Southeast 118.120° (118°07′12″) 12 SEbE Southeast by East 118.130° (118°07′48″) 13 SE Southeast 135.000° (135°00′00″) 14 SEbS Southeast by South 151.870° (151°52′12″) 15 SSE South-Southeast 151.880° (151°52′48″) 16 SbE South by East 168.750° (168°45′00″) 17 S South 185.620° (185°37′12″) 18 SbW South by West 185.630° (185°37′48″) 19 SSW South-Southwest 202.500° (202°30′00″) 20 SWbS Southwest by South 219.370° (219°22′12″) 21 SW Southwest 219.380° (219°22′48″) 22 SWbW Southwest by West 236.250° (236°15′00″) 23 WSW Southwest 253.120° (253°07′12″) 24 WbS West by South 253.130° (253°07′48″) 25 W West 270.000° (270°00′00″) 26 WbN West by North 286.870° (286°52′12″) 27 WNW West-Northwest 286.880° (286°52′48″) 28 NWbW Northwest by West 303.750° (303°45′00″) 29 NW Northwest 320.620° (320°37′12″) 30 NWbN Northwest by North 320.630° (320°37′48″) 31 NNW North-Northwest 337.500° (337°30′00″) 32 NbW North by West 354.370° (354°22′12″) 1 N North 354.380° (354°22′48″)
Ruby
First I want a hash Headings = {1 => "north", 2 => "north by east", ...}. This program outputs the hash so that I can skip typing all 32 pairs.
<lang ruby>h = [] ["north", "east", "south", "west", "north"].each_cons(2) do |a, b|
c = if ["north", "south"].include? a then "#{a}#{b}" else "#{b}#{a}" end h << a h << "#{a} by #{b}" h << "#{a}-#{c}" h << "#{c} by #{a}" h << "#{c}" h << "#{c} by #{b}" h << "#{b}-#{c}" h << "#{b} by #{a}"
end
puts "Headings = {" h.each_with_index { |n, i| puts " #{i+1} => #{n.inspect}," } puts "}"</lang>
I paste the output from the first program into a second program, then add a method to find a compass heading from degrees, and some code to output the table.
<lang ruby>Headings = {
1 => "north", 2 => "north by east", 3 => "north-northeast", 4 => "northeast by north", 5 => "northeast", 6 => "northeast by east", 7 => "east-northeast", 8 => "east by north", 9 => "east", 10 => "east by south", 11 => "east-southeast", 12 => "southeast by east", 13 => "southeast", 14 => "southeast by south", 15 => "south-southeast", 16 => "south by east", 17 => "south", 18 => "south by west", 19 => "south-southwest", 20 => "southwest by south", 21 => "southwest", 22 => "southwest by west", 23 => "west-southwest", 24 => "west by south", 25 => "west", 26 => "west by north", 27 => "west-northwest", 28 => "northwest by west", 29 => "northwest", 30 => "northwest by north", 31 => "north-northwest", 32 => "north by west",
}
- Finds the 32-point compass heading nearest _degrees_, and
- returns an array of the index and name.
- p heading(60)
- # => [6, "northeast by east"]
def heading(degrees)
i = degrees.quo(360).*(32).round.%(32).+(1) [i, Headings[i]]
end
- an array of angles, in degrees
angles = (0..32).map { |i| i * 11.25 + [0, 5.62, -5.62][i % 3] }
angles.each do |degrees|
index, name = heading degrees printf "%2d %20s %6g\n", index, name.center(20), degrees
end</lang>
The second program outputs this table:
1 north 0 2 north by east 16.87 3 north-northeast 16.88 4 northeast by north 33.75 5 northeast 50.62 6 northeast by east 50.63 7 east-northeast 67.5 8 east by north 84.37 9 east 84.38 10 east by south 101.25 11 east-southeast 118.12 12 southeast by east 118.13 13 southeast 135 14 southeast by south 151.87 15 south-southeast 151.88 16 south by east 168.75 17 south 185.62 18 south by west 185.63 19 south-southwest 202.5 20 southwest by south 219.37 21 southwest 219.38 22 southwest by west 236.25 23 west-southwest 253.12 24 west by south 253.13 25 west 270 26 west by north 286.87 27 west-northwest 286.88 28 northwest by west 303.75 29 northwest 320.62 30 northwest by north 320.63 31 north-northwest 337.5 32 north by west 354.37 1 north 354.38
Seed7
<lang seed7>$ include "seed7_05.s7i";
include "float.s7i";
const array string: names is [] ("North", "North by east", "North-northeast", "Northeast by north",
"Northeast", "Northeast by east", "East-northeast", "East by north", "East", "East by south", "East-southeast", "Southeast by east", "Southeast", "Southeast by south", "South-southeast", "South by east", "South", "South by west", "South-southwest", "Southwest by south", "Southwest", "Southwest by west", "West-southwest", "West by south", "West", "West by north", "West-northwest", "Northwest by west", "Northwest", "Northwest by north", "North-northwest", "North by west", "North");
const proc: main is func
local const array float: degrees is [] (0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38); var integer: index is 0; var integer: nameIndex is 0; begin for key index range degrees do nameIndex := round(degrees[index] * 32.0 / 360.0); writeln(index lpad 2 <& " " <& names[succ(nameIndex rem 32)] rpad 22 <& degrees[index] digits 2 lpad 6); end for; end func;</lang>
Output:
1 North 0.00 2 North by east 16.87 3 North-northeast 16.88 4 Northeast by north 33.75 5 Northeast 50.62 6 Northeast by east 50.63 7 East-northeast 67.50 8 East by north 84.37 9 East 84.38 10 East by south 101.25 11 East-southeast 118.12 12 Southeast by east 118.13 13 Southeast 135.00 14 Southeast by south 151.87 15 South-southeast 151.88 16 South by east 168.75 17 South 185.62 18 South by west 185.63 19 South-southwest 202.50 20 Southwest by south 219.37 21 Southwest 219.38 22 Southwest by west 236.25 23 West-southwest 253.12 24 West by south 253.13 25 West 270.00 26 West by north 286.87 27 West-northwest 286.88 28 Northwest by west 303.75 29 Northwest 320.62 30 Northwest by north 320.63 31 North-northwest 337.50 32 North by west 354.37 33 North 354.38
Tcl
<lang tcl>proc angle2compass {angle} {
set dirs {
N NbE N-NE NEbN NE NEbE E-NE EbN E EbS E-SE SEbE SE SEbS S-SE SbE S SbW S-SW SWbS SW SWbW W-SW WbS W WbN W-NW NWbW NW NWbN N-NW NbW
} set unpack {N "north" E "east" W "west" S "south" b " by "}
# Compute the width of each compass segment set sep [expr {360.0 / [llength $dirs]}]
# Work out which segment contains the compass angle set dir [expr {round((fmod($angle + $sep/2, 360) - $sep/2) / $sep)}]
# Convert to a named direction, capitalized as in the wikipedia article return [string totitle [string map $unpack [lindex $dirs $dir]]]
}
- Box the compass, using the variable generation algorithm described
for {set i 0} {$i < 33} {incr i} {
set heading [expr {$i * 11.25}] if {$i % 3 == 1} {set heading [expr {$heading + 5.62}]} if {$i % 3 == 2} {set heading [expr {$heading - 5.62}]} set index [expr {$i % 32 + 1}]
# Pretty-print the results of converting an angle to a compass heading puts [format "%2i %-18s %7.2f°" $index [angle2compass $heading] $heading]
}</lang> Output:
1 North 0.00° 2 North by east 16.87° 3 North-northeast 16.88° 4 Northeast by north 33.75° 5 Northeast 50.62° 6 Northeast by east 50.63° 7 East-northeast 67.50° 8 East by north 84.37° 9 East 84.38° 10 East by south 101.25° 11 East-southeast 118.12° 12 Southeast by east 118.13° 13 Southeast 135.00° 14 Southeast by south 151.87° 15 South-southeast 151.88° 16 South by east 168.75° 17 South 185.62° 18 South by west 185.63° 19 South-southwest 202.50° 20 Southwest by south 219.37° 21 Southwest 219.38° 22 Southwest by west 236.25° 23 West-southwest 253.12° 24 West by south 253.13° 25 West 270.00° 26 West by north 286.87° 27 West-northwest 286.88° 28 Northwest by west 303.75° 29 Northwest 320.62° 30 Northwest by north 320.63° 31 North-northwest 337.50° 32 North by west 354.37° 1 North 354.38°
Visual Basic .NET
<lang vbnet>Module BoxingTheCompass
Dim _points(32) As String
Sub Main() BuildPoints()
Dim heading As Double = 0D
For i As Integer = 0 To 32 heading = i * 11.25 Select Case i Mod 3 Case 1 heading += 5.62 Case 2 heading -= 5.62 End Select
Console.WriteLine("{0,2}: {1,-18} {2,6:F2}°", (i Mod 32) + 1, InitialUpper(GetPoint(heading)), heading) Next End Sub
Private Sub BuildPoints() Dim cardinal As String() = New String() {"north", "east", "south", "west"} Dim pointDesc As String() = New String() {"1", "1 by 2", "1-C", "C by 1", "C", "C by 2", "2-C", "2 by 1"}
Dim str1, str2, strC As String
For i As Integer = 0 To 3 str1 = cardinal(i) str2 = cardinal((i + 1) Mod 4) strC = IIf(str1 = "north" Or str1 = "south", str1 & str2, str2 & str1) For j As Integer = 0 To 7 _points(i * 8 + j) = pointDesc(j).Replace("1", str1).Replace("2", str2).Replace("C", strC) Next Next End Sub
Private Function InitialUpper(ByVal s As String) As String Return s.Substring(0, 1).ToUpper() & s.Substring(1) End Function
Private Function GetPoint(ByVal Degrees As Double) As String Dim testD As Double = (Degrees / 11.25) + 0.5 Return _points(CInt(Math.Floor(testD Mod 32))) End Function
End Module </lang> Output:
1: North 0.00° 2: North by east 16.87° 3: North-northeast 16.88° 4: Northeast by north 33.75° 5: Northeast 50.62° 6: Northeast by east 50.63° 7: East-northeast 67.50° 8: East by north 84.37° 9: East 84.38° 10: East by south 101.25° 11: East-southeast 118.12° 12: Southeast by east 118.13° 13: Southeast 135.00° 14: Southeast by south 151.87° 15: South-southeast 151.88° 16: South by east 168.75° 17: South 185.62° 18: South by west 185.63° 19: South-southwest 202.50° 20: Southwest by south 219.37° 21: Southwest 219.38° 22: Southwest by west 236.25° 23: West-southwest 253.12° 24: West by south 253.13° 25: West 270.00° 26: West by north 286.87° 27: West-northwest 286.88° 28: Northwest by west 303.75° 29: Northwest 320.62° 30: Northwest by north 320.63° 31: North-northwest 337.50° 32: North by west 354.37° 1: North 354.38°