SEDOLs: Difference between revisions
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Revision as of 06:48, 29 October 2011
You are encouraged to solve this task according to the task description, using any language you may know.
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030
Produce this output:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300
For extra credit, check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
C.f. Luhn test
ActionScript
<lang ActionScript>//Return the code corresponding to a given character. //ActionScript does not have a character type, so 1-digit strings //are used instead function toSEDOLCode(char:String):uint { //Make sure only a single character was sent. if(char.length != 1) throw new Error("toSEDOL expected string length of 1, got " + char.length); //Character is uppercase if (char >= "A" && char <= "Z") { return SEDOL.charCodeAt() + 10 - "A".charCodeAt(); } //Character is numeric else if (char >= "0" && char <= "9"){ return uint(char); } //Error: character is neither numeric nor uppercase else{ throw new Error("toSEDOLCode expected numeric or uppercase character, recieved " + char); } } //Calculate the weighted sum for the SEDOL. function toSum(str:String):uint { if(str.length != 6) throw new Error("toSum expected length 6, recieved " + str.length); var sum:uint=0; for (var i:uint = 0; i < str.length; i++) sum+=toSEDOLCode(str.charAt(i))*[1,3,1,7,3,9][i]; return sum; } //Calculate the check digit from the weighted sum. function toCheck(num:int):uint { return (10 -(num % 10)) % 10; } //Print the SEDOL with the check digit added. function printWithCheck(SEDOL:String):void { trace(SEDOL + toCheck(toSum(SEDOL))); } printWithCheck("710889"); printWithCheck("B0YBKJ"); printWithCheck("406566"); printWithCheck("B0YBLH"); printWithCheck("228276"); printWithCheck("B0YBKL"); printWithCheck("557910"); printWithCheck("B0YBKR"); printWithCheck("585284"); printWithCheck("B0YBKT"); printWithCheck("B00030");</lang>
Ada
<lang ada>with Ada.Text_IO; use Ada.Text_IO;
procedure Test_SEDOL is
subtype SEDOL_String is String (1..6); type SEDOL_Sum is range 0..9;
function Check (SEDOL : SEDOL_String) return SEDOL_Sum is Weight : constant array (SEDOL_String'Range) of Integer := (1,3,1,7,3,9); Sum : Integer := 0; Item : Integer; begin for Index in SEDOL'Range loop Item := Character'Pos (SEDOL (Index)); case Item is when Character'Pos ('0')..Character'Pos ('9') => Item := Item - Character'Pos ('0'); when Character'Pos ('B')..Character'Pos ('D') | Character'Pos ('F')..Character'Pos ('H') | Character'Pos ('J')..Character'Pos ('N') | Character'Pos ('P')..Character'Pos ('T') | Character'Pos ('V')..Character'Pos ('Z') => Item := Item - Character'Pos ('A') + 10; when others => raise Constraint_Error; end case; Sum := Sum + Item * Weight (Index); end loop; return SEDOL_Sum ((-Sum) mod 10); end Check;
Test : constant array (1..10) of SEDOL_String := ( "710889", "B0YBKJ", "406566", "B0YBLH", "228276", "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT" );
begin
for Index in Test'Range loop Put_Line (Test (Index) & Character'Val (Character'Pos ('0') + Check (Test (Index)))); end loop;
end Test_SEDOL;</lang> The function Check raises Constraint_Error upon an invalid input. The calculated sum is trimmed using (-sum) mod 10, which is mathematically equivalent to (10 - (sum mod 10)) mod 10.
Sample output:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7
ALGOL 68
<lang algol68>[]INT sedol weights = (1, 3, 1, 7, 3, 9); STRING reject = "AEIOUaeiou";
PROC strcspn = (STRING s,reject)INT: (
INT out:=0; FOR i TO UPB s DO IF char in string(s[i], LOC INT, reject) THEN return out FI; out:=i OD; return out: out
);
PROC sedol checksum = (REF STRING sedol6)INT: (
INT out;
INT len := UPB sedol6; INT sum := 0; IF sedol6[len-1] = REPR 10 THEN len-:=1; sedol6[len]:=null char FI; IF len = 7 THEN putf(stand error, ($"SEDOL code already checksummed? ("g")"l$, sedol6)); out := ABS ( BIN ABS sedol6[6] AND 16r7f); return out FI; IF len > 7 OR len < 6 OR strcspn(sedol6, reject) /= 6 THEN putf(stand error, ($"not a SEDOL code? ("g")"l$, sedol6)); out := -1; return out FI; FOR i TO UPB sedol6 DO sum+:=sedol weights[i]* IF is digit(sedol6[i]) THEN ABS sedol6[i]- ABS "0" ELIF is alpha(sedol6[i]) THEN (ABS to upper(sedol6[i])-ABS "A") + 10 ELSE putf(stand error, $"SEDOL with not alphanumeric digit"l$); out:=-1; return out FI OD; out := (10 - (sum MOD 10)) MOD 10 + ABS "0"; return out: out
);
main: (
STRING line; on logical file end(stand in, (REF FILE f)BOOL: done); DO getf(stand in, ($gl$,line)); INT sr := sedol checksum(line); IF sr > 0 THEN printf(($ggl$, line, REPR sedol checksum(line))) FI OD; done: SKIP
)</lang> Output:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7
AutoHotkey
ahk forum: discussion <lang AutoHotkey>MsgBox % SEDOL("710889") ;7108899 MsgBox % SEDOL("B0YBKJ") ;B0YBKJ7 MsgBox % SEDOL("406566") ;4065663 MsgBox % SEDOL("B0YBLH") ;B0YBLH2 MsgBox % SEDOL("228276") ;2282765 MsgBox % SEDOL("B0YBKL") ;B0YBKL9 MsgBox % SEDOL("557910") ;5579107 MsgBox % SEDOL("B0YBKR") ;B0YBKR5 MsgBox % SEDOL("585284") ;5852842 MsgBox % SEDOL("B0YBKT") ;B0YBKT7
SEDOL(w) {
Static w1:=1,w2:=3,w3:=1,w4:=7,w5:=3,w6:=9 Loop Parse, w s += ((c:=Asc(A_LoopField))>=Asc("A") ? c-Asc("A")+10 : c-Asc("0")) * w%A_Index% Return w mod(10-mod(s,10),10)
}</lang>
AWK
Validate or calculate checksum of SEDOL codes read from standard input (one per line) <lang awk>function ord(a) {
return amap[a]
}
function sedol_checksum(sed) {
sw[1] = 1; sw[2] = 3; sw[3] = 1 sw[4] = 7; sw[5] = 3; sw[6] = 9 sum = 0 for(i=1; i <= 6; i++) { c = substr(toupper(sed), i, 1) if ( c ~ /digit:/ ) { sum += c*sw[i] } else { sum += (ord(c)-ord("A")+10)*sw[i] } } return (10 - (sum % 10)) % 10
}
BEGIN { # prepare amap for ord
for(_i=0;_i<256;_i++) { astr = sprintf("%c", _i) amap[astr] = _i }
}
/[AEIOUaeiou]/ {
print "'" $0 "' not a valid SEDOL code" next
} {
if ( (length($0) > 7) || (length($0) < 6) ) { print "'" $0 "' is too long or too short to be valid SEDOL" next } sedol = substr($0, 1, 6) sedolcheck = sedol_checksum(sedol) if ( length($0) == 7 ) { if ( (sedol sedolcheck) != $0 ) { print sedol sedolcheck " (original " $0 " has wrong check digit" } else { print sedol sedolcheck } } else { print sedol sedolcheck }
}</lang>
BASIC
<lang qbasic>DECLARE FUNCTION getSedolCheckDigit! (str AS STRING) DO
INPUT a$ PRINT a$ + STR$(getSedolCheckDigit(a$))
LOOP WHILE a$ <> ""
FUNCTION getSedolCheckDigit (str AS STRING)
IF LEN(str) <> 6 THEN PRINT "Six chars only please" EXIT FUNCTION END IF str = UCASE$(str) DIM mult(6) AS INTEGER mult(1) = 1: mult(2) = 3: mult(3) = 1 mult(4) = 7: mult(5) = 3: mult(6) = 9 total = 0 FOR i = 1 TO 6 s$ = MID$(str, i, 1) IF s$ = "A" OR s$ = "E" OR s$ = "I" OR s$ = "O" OR s$ = "U" THEN PRINT "No vowels" EXIT FUNCTION END IF IF ASC(s$) >= 48 AND ASC(s$) <= 57 THEN total = total + VAL(s$) * mult(i) ELSE total = total + (ASC(s$) - 55) * mult(i) END IF
NEXT i getSedolCheckDigit = (10 - (total MOD 10)) MOD 10
END FUNCTION</lang>
C
Notes: it reads the codes from standard input, one per line (linefeed terminated); the input encoding must meet the following specifications: single byte encoding, digits (0-9) must have codes that follow the same order of the digits (0, 1, 2, ...) and similar for letters, the encoding must match the one used with the compiled source (likely, ASCII based encodings). This should happen 99% of the time (for ASCII, ISO-8859 family and UTF-8 have the same byte encoding for alphanumeric characters).
<lang c>#include <stdio.h>
- include <ctype.h>
- include <string.h>
int sedol_weights[] = {1, 3, 1, 7, 3, 9}; const char *reject = "AEIOUaeiou";
int sedol_checksum(const char *sedol6) {
int len = strlen(sedol6); int sum = 0, i;
if ( len == 7 ) { fprintf(stderr, "SEDOL code already checksummed? (%s)\n", sedol6); return sedol6[6] & 0x7f; } if ( (len > 7) || (len < 6) || ( strcspn(sedol6, reject) != 6 )) { fprintf(stderr, "not a SEDOL code? (%s)\n", sedol6); return -1; } for(i=0; i < 6; i++) { if ( isdigit(sedol6[i]) ) { sum += (sedol6[i]-'0')*sedol_weights[i]; } else if ( isalpha(sedol6[i]) ) { sum += ((toupper(sedol6[i])-'A') + 10)*sedol_weights[i]; } else { fprintf(stderr, "SEDOL with not alphanumeric digit\n"); return -1; } } return (10 - (sum%10))%10 + '0';
}
- define MAXLINELEN 10
int main() {
char line[MAXLINELEN]; int sr, len; while( fgets(line, MAXLINELEN, stdin) != NULL ) { len = strlen(line); if ( line[len-1] == '\n' ) line[len-1]='\0'; sr = sedol_checksum(line); if ( sr > 0 ) printf("%s%c\n", line, sr); } return 0;
}</lang>
Fed the input list from the task description, the output is:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7
C++
<lang cpp>
- include <numeric>
- include <algorithm>
- include <cctype>
- include <iostream>
- include <stdexcept>
- include <iterator>
- include <vector>
using namespace std;
const int weights[] = {1,3,1,7,3,9}; const string valid_chars = "BCDFGHJKLMNPQRSTVWXYZ0123456789";
int char_value(char c){ return isalpha(c) ? c -'A' + 10 : c - '0'; }
int sedol_checksum(string const& sedol) {
//Check contents if(sedol.size() != 6) throw length_error("length of sedol string != 6"); if(sedol.find_first_not_of(valid_chars) != std::string::npos) throw invalid_argument("sedol string contains disallowed characters");
vector<int> char_values; transform(sedol.begin(), sedol.end(), back_inserter(char_values), char_value); const int weighted_sum = inner_product(char_values.begin(), char_values.end(), weights, 0); return (10 - (weighted_sum % 10)) % 10;
}
int main() {
char * inputs[] = { "710889", "B0YBKJ", "406566", "B0YBLH", "228276", "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT", "B00030" }; const size_t n_inputs = sizeof(inputs) / sizeof(*inputs);
for(size_t i = 0; i != n_inputs; ++i) { cout << inputs[i] << sedol_checksum(inputs[i]) << "\n"; }
} </lang>
C#
<lang csharp>static int[] sedol_weights = { 1, 3, 1, 7, 3, 9 }; static int sedolChecksum(string sedol) {
int len = sedol.Length; int sum = 0;
if (len == 7) //SEDOL code already checksummed? return (int)sedol[6];
if ((len > 7) || (len < 6) || System.Text.RegularExpressions.Regex.IsMatch(sedol, "[AEIOUaeiou]+")) //invalid SEDOL return -1;
for (int i = 0; i < 6; i++) { if (Char.IsDigit(sedol[i])) sum += (((int)sedol[i] - 48) * sedol_weights[i]);
else if (Char.IsLetter(sedol[i])) sum += (((int)Char.ToUpper(sedol[i]) - 55) * sedol_weights[i]);
else return -1;
}
return (10 - (sum % 10)) % 10;
}</lang>
Common Lisp
Implemented from scratch using the description on Wikipedia as specification.
<lang lisp>(defun append-sedol-check-digit (sedol &key (start 0) (end (+ start 6)))
(assert (<= 0 start end (length sedol))) (assert (= (- end start) 6)) (loop :with checksum = 0 :for weight :in '(1 3 1 7 3 9) :for index :upfrom start :do (incf checksum (* weight (digit-char-p (char sedol index) 36))) :finally (let* ((posn (- 10 (mod checksum 10)))
(head (subseq sedol start end)) (tail (digit-char posn))) (return (concatenate 'string head (list tail))))))</lang>
D
Functional style: <lang d>import std.stdio, std.algorithm, std.string, std.numeric, std.ctype;
char checksum(in char[] sedol) in {
assert(sedol.length == 6); foreach (c; sedol) assert(std.ctype.isdigit(c) || (c > 'A' && c <= 'Z' && !canFind("AEIOU", c)));
} body {
int c2v(in dchar c){ return isdigit(c) ? c-'0' : c-'A'+10; } int d = dotProduct(map!c2v(sedol), [1,3,1,7,3,9]); return cast(char)('0' + 10 - (d % 10));
}
void main() {
foreach (sedol; "710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT".split()) writeln(sedol, checksum(sedol));
}</lang> Output:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7
Longer faster lower-level version, same output: <lang d>import std.stdio, std.algorithm, std.string, std.numeric, std.ctype;
/*nothrow pure*/ char sedolChecksum(in char[] sedol) in {
assert(sedol.length == 6, "SEDOL must be 6 chars long."); enum uint mask = 0b11_1110_1111_1011_1110_1110_1110;
foreach (c; sedol) assert(std.ctype.isdigit(c) || (c > 'A' && c <= 'Z' && ((1U << (c - 'A')) & mask)), "SEDOL with wrong char.");
} out(result) {
assert(isdigit(result)); int c2v(in dchar c){ return isdigit(c) ? c-'0' : c-'A'+10; } int d = dotProduct(map!c2v(sedol), [1,3,1,7,3,9]); assert((d + result - '0') % 10 == 0);
} body {
enum int[] weights = [1, 3, 1, 7, 3, 9];
int sum = 0; foreach (i, c; sedol) { if (std.ctype.isdigit(c)) sum += (c - '0') * weights[i]; else sum += (c - 'A' + 10) * weights[i]; }
return cast(char)('0' + 10 - (sum % 10));
}
void main() {
foreach (s; ["710889", "B0YBKJ", "406566", "B0YBLH", "228276", "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT"]) writeln(s, sedolChecksum(s));
}</lang> Short version (same output): <lang d>import std.stdio, std.algorithm, std.string, std.numeric;
auto checksum(string s) {
auto m = map!q{ a>='0' && a<='9' ? a-'0' : a-'A'+10 }(s); return '0' + 10 - dotProduct(m, [1,3,1,7,3,9]) % 10;
}
void main() {
foreach (sedol; "710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT".split()) writeln(sedol, checksum(sedol));
}</lang>
E
<lang e>def weights := [1,3,1,7,3,9] def Digit := ('0'..'9') def Letter := ('B'..'D'|'F'..'H'|'J'..'N'|'P'..'T'|'V'..'Z') def sedolCharValue(c) {
switch (c) { match digit :Digit { return digit - '0' } match letter :Letter { return letter - 'A' } }
}
def checksum(sedol :String) {
require(sedol.size() == 6) var sum := 0 for i => c in sedol { sum += weights[i] * sedolCharValue(c) } return E.toString((10 - sum %% 10) %% 10)
}
def addChecksum(sedol :String) {
return sedol + checksum(sedol)
}
for sedol in "710889
B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT".trim().split("\n") { println(addChecksum(sedol.trim()))
}</lang>
Forth
<lang forth>create weight 1 , 3 , 1 , 7 , 3 , 9 ,
- char>num ( '0-9A-Z' -- 0..35 )
dup [char] 9 > 7 and - [char] 0 - ;
- check+ ( sedol -- sedol' )
6 <> abort" wrong SEDOL length" 0 ( sum ) 6 0 do over I + c@ char>num weight I cells + @ * + loop 10 mod 10 swap - 10 mod [char] 0 + over 6 + c! 7 ;
- sedol" [char] " parse check+ type ;
sedol" 710889" 7108899 ok sedol" B0YBKJ" B0YBKJ7 ok sedol" 406566" 4065663 ok sedol" B0YBLH" B0YBLH2 ok sedol" 228276" 2282765 ok sedol" B0YBKL" B0YBKL9 ok sedol" 557910" 5579107 ok sedol" B0YBKR" B0YBKR5 ok sedol" 585284" 5852842 ok sedol" B0YBKT" B0YBKT7 ok</lang>
Fortran
<lang fortran>MODULE SEDOL_CHECK
IMPLICIT NONE CONTAINS FUNCTION Checkdigit(c) CHARACTER :: Checkdigit CHARACTER(6), INTENT(IN) :: c CHARACTER(36) :: alpha = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" INTEGER, DIMENSION(6) :: weights = (/ 1, 3, 1, 7, 3, 9 /), temp INTEGER :: i, n
DO i = 1, 6 temp(i) = INDEX(alpha, c(i:i)) - 1 END DO temp = temp * weights n = MOD(10 - (MOD(SUM(temp), 10)), 10) Checkdigit = ACHAR(n + 48) END FUNCTION Checkdigit
END MODULE SEDOL_CHECK
PROGRAM SEDOLTEST
USE SEDOL_CHECK IMPLICIT NONE CHARACTER(31) :: valid = "0123456789BCDFGHJKLMNPQRSTVWXYZ" CHARACTER(6) :: codes(10) = (/ "710889", "B0YBKJ", "406566", "B0YBLH", "228276" , & "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT" /) CHARACTER(7) :: sedol INTEGER :: i, invalid
DO i = 1, 10 invalid = VERIFY(codes(i), valid) IF (invalid == 0) THEN sedol = codes(i) sedol(7:7) = Checkdigit(codes(i)) ELSE sedol = "INVALID" END IF WRITE(*, "(2A9)") codes(i), sedol END DO
END PROGRAM SEDOLTEST</lang> Output
710889 7108899 B0YBKJ B0YBKJ7 406566 4065663 B0YBLH B0YBLH2 228276 2282765 B0YBKL B0YBKL9 557910 5579107 B0YBKR B0YBKR5 585284 5852842 B0YBKT B0YBKT7
Go
<lang go> package main
import (
"fmt" "strings"
)
const input = `710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030
B B0003 B000300 A00030 E00030 I00030 O00030 U00030 β00030 β0003`
var weight = [...]int{1,3,1,7,3,9}
func csd(code string) string {
switch len(code) { case 6: case 0: return "No data" default: return "Invalid length" } var n, sum int for i, c := range code { switch { case c >= '0' && c <= '9': n = c - '0' case c >= 'B' && c <= 'Z' && c != 'E' && c != 'I' && c != 'O' && c != 'U': n = c - 'B' + 11 default: return "Invalid character" } sum += n*weight[i] } return string('9'-(sum-1)%10)
}
func main() {
for _, s := range strings.Split(input, "\n") { d := csd(s) if len(d) > 1 { fmt.Printf(":%s: %s\n", s, d) } else { fmt.Println(s + d) } }
} </lang> Output:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 :: No data :B: Invalid length :B0003: Invalid length :B000300: Invalid length :A00030: Invalid character :E00030: Invalid character :I00030: Invalid character :O00030: Invalid character :U00030: Invalid character :β00030: Invalid length :β0003: Invalid character
Haskell
<lang haskell>import Data.Char
char2value c | c `elem` "AEIOU" = error "No vowels."
| c >= '0' && c <= '9' = ord c - ord '0' | c >= 'A' && c <= 'Z' = ord c - ord 'A' + 10
sedolweight = [1,3,1,7,3,9]
checksum sedol = show ((10 - (tmp `mod` 10)) `mod` 10)
where tmp = sum $ zipWith (*) sedolweight $ map char2value sedol
main = mapM_ (\sedol -> putStrLn $ sedol ++ checksum sedol)
[ "710889", "B0YBKJ", "406566", "B0YBLH", "228276", "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT" ]</lang>
Icon and Unicon
<lang Icon>procedure main() every write(sedol("710889"|"B0YBKJ"|"406566"|"B0YBLH"|"228276"|
"B0YBKL"|"557910"|"B0YBKR"|"585284"|"B0YBKT"|"B00030"))
end
procedure sedol(x) #: return the completed sedol with check digit static w,c initial {
every (i := -1, c := table())[!(&digits||&ucase)] := i +:= 1 # map chars every c[!"AEIOU"] := &null # delete vowels w := [1,3,1,7,3,9] # weights }
if *(x := map(x,&lcase,&ucase)) = *w then { # match lengths
every (t :=0, i := 1 to *x) do t +:= \c[x[i]]*w[i] | fail # accumulate weighted chars return x || (10 - (t%10)) % 10 # complete }
end</lang>
J
There are several ways to perform this in J. This most closely follows the algorithmic description at Wikipedia: <lang j>sn =. '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ' ac0 =: (, 10 | 1 3 1 7 3 9 +/@:* -)&.(sn i. |:)</lang> However, because J is so concise, having written the above, it becomes clear that the negation (-) is unneccsary.
The fundamental operation is the linear combination (+/@:*) and neither argument is "special". In particular, the coefficients are just another array participating in the calculation, and there's no reason we can't modify them as easily as the input array. Having this insight, it is obvious that manipulating the coefficients, rather than the input array, will be more efficient (because the coefficients are fixed at small size, while the input array can be arbitrarily large).
Which leads us to this more efficient formulation: <lang j>ac1 =: (, 10 | (10 - 1 3 1 7 3 9) +/@:* ])&.(sn i. |:)</lang> which reduces to: <lang j>ac1 =: (, 10 | 9 7 9 3 7 1 +/@:* ])&.(sn i. |:)</lang> Which is just as concise as ac0, but faster.
Following this train of thought, our array thinking leads us to realize that even the modulous isn't neccesary. The number of SEDOL numbers is finite, as is the number of coefficients; therefore the number of possible linear combinations of these is finite. In fact, there are only 841 possible outcomes. This is a small number, and can be efficiently stored as a lookup table (even better, since the outcomes will be mod 10, they are restricted to the digits 0-9, and they repeat).
Which leads us to: <lang j>ac2 =. (,"1 0 (841 $ '0987654321') {~ 1 3 1 7 3 9 +/ .*~ sn i. ])</lang> Which is more than twice as fast as even the optimized formulation (ac1), though it is slightly longer.
Java
<lang java>import java.util.Scanner;
public class SEDOL{ public static void main(String[] args){ Scanner sc = new Scanner(System.in); while(sc.hasNext()){ String sedol = sc.next(); System.out.println(sedol + getSedolCheckDigit(sedol)); } }
private static final int[] mult = {1, 3, 1, 7, 3, 9};
public static int getSedolCheckDigit(String str){ if(!validateSedol(str)){ System.err.println("SEDOL strings must contain six characters with no vowels."); return -1; } str = str.toUpperCase(); int total = 0; for(int i = 0;i < 6; i++){ char s = str.charAt(i); total += Character.digit(s, 36) * mult[i]; } return (10 - (total % 10)) % 10; }
public static boolean validateSedol(String str){ return (str.length() == 6) && !str.toUpperCase().matches(".*?[AEIOU].*?"); } }</lang>
JavaScript
<lang javascript>function sedol(input) {
return input + sedol_check_digit(input);
}
var weight = [1, 3, 1, 7, 3, 9, 1]; function sedol_check_digit(char6) {
if (char6.search(/^[0-9BCDFGHJKLMNPQRSTVWXYZ]{6}$/) == -1) throw "Invalid SEDOL number '" + char6 + "'"; var chars = char6.split(); var sum = 0; for (var i in chars) sum += weight[i] * char_to_value(chars[i]); var check = (10 - sum%10) % 10; return check.toString();
}
function char_to_value(ch) {
var val = ch.charCodeAt(0); if (48 <= val && val <= 57) return val - 48; else return val - 65 + 10;
}
var input = [
'710889', 'B0YBKJ', '406566', 'B0YBLH', '228276', 'B0YBKL', '557910', 'B0YBKR', '585284', 'B0YBKT', "BOATER" , "12345", "123456", "1234567"
];
var expected = [
'7108899', 'B0YBKJ7', '4065663', 'B0YBLH2', '2282765', 'B0YBKL9', '5579107', 'B0YBKR5', '5852842', 'B0YBKT7', null, null, '1234563', null
];
for (var i in input) {
try { var sedolized = sedol(input[i]); if (sedolized == expected[i]) print(sedolized); else print("error: calculated sedol for input " + input[i] + " is " + sedolized + ", but it should be " + expected[i] ); } catch (e) { print("error: " + e); }
}</lang> output
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 error: Invalid SEDOL number 'BOATER' error: Invalid SEDOL number '12345' 1234563 error: Invalid SEDOL number '1234567'
M4
<lang M4>divert(-1) changequote(`[',`]') define([_bar],include(sedol.inp)) define([eachlineA],
[ifelse(eval($2>0),1, [$3(substr([$1],0,$2))[]eachline(substr([$1],incr($2)),[$3])])])
define([eachline],[eachlineA([$1],index($1,[ ]),[$2])]) define([_idx],
[index([0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ],substr($1,$2,1))])
define([_wsum],
[eval(_idx($1,0)+_idx($1,1)*3+_idx($1,2)+_idx($1,3)*7+_idx($1,4)*3+_idx($1,5)*9)])
define([checksum],
[$1[]eval((10-_wsum($1)%10)%10)
]) divert eachline(_bar,[checksum])</lang>
Modula-3
<lang modula3>MODULE SEDOL EXPORTS Main;
IMPORT IO, Fmt, Text, Stdio;
EXCEPTION BadSedol(TEXT);
VAR test := ARRAY [1..10] OF TEXT {"710889", "B0YBKJ", "406566", "B0YBLH",
"228276", "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT" };
PROCEDURE Check(sed: TEXT): INTEGER RAISES {BadSedol}=
VAR weights := ARRAY [0..5] OF INTEGER {1, 3, 1, 7, 3, 9}; result, d: INTEGER; char: CHAR; BEGIN IF Text.Length(sed) # 6 THEN RAISE BadSedol("ERROR: Must be 6 digits."); END; result := 0; FOR i := 0 TO 5 DO char := Text.GetChar(sed, i); CASE char OF | '0'..'9' => d := ORD(char) - ORD('0'); | 'B'..'D', 'F'..'H', 'J'..'N', 'P'..'T', 'V'..'Z' => d := ORD(char) - ORD('A') + 10; ELSE RAISE BadSedol("ERROR: Must be numbers or (non-vowel) letters."); END; INC(result, d * weights[i]); END; result := (10 - (result MOD 10)) MOD 10; RETURN result; END Check;
BEGIN
TRY FOR i := FIRST(test) TO LAST(test) DO IO.Put(test[i] & Fmt.Char(VAL(ORD('0') + Check(test[i]), CHAR)) & "\n"); END; EXCEPT | BadSedol(text) => IO.Put(text & "\n", Stdio.stderr); END;
END SEDOL.</lang> Output:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7
MUMPS
<lang MUMPS>SEDOL
NEW A,B
SEDOL1
READ !,"Enter the first 6 digits of a SEDOL: ",A SET B=$$SEDOLCHK(A) WRITE !,$SELECT($LENGTH(B)=1:"Full SEDOL is "_A_B,1:B) GOTO SEDOL1 QUIT
SEDOLCHK(STOCK)
NEW WT,VAL,I,CHK,C,FLAG SET WT="1317391",VAL=0,FLAG=0 FOR I=1:1:6 SET C=$$TOUPPER($EXTRACT(STOCK,I)),VAL=VAL+($$SEDVAL(C)*$EXTRACT(WT,I)) SET:"AEIOUaeiou"[C FLAG=1 SET:$LENGTH(STOCK)'=6 FLAG=1 KILL WT,I,CHK,C QUIT $SELECT(FLAG:"INVALID",'FLAG:(10-(VAL#10))#10)
SEDVAL(X)
QUIT $SELECT($ISVALIDNUM(X):X,1:$ASCII(X)-$ASCII("@")+9)
TOUPPER(X)
NEW UP,LO SET UP="ABCDEFGHIJKLMNOPQRSTUVWXYZ",LO="abcdefghijklmnopqrstuvwxyz" QUIT $TRANSLATE(X,LO,UP)</lang>
Examples:
USER>D SEDOL^ROSETTA Enter the first 6 digits of a SEDOL: 710889 Full SEDOL is 7108899 Enter the first 6 digits of a SEDOL: B0YBKJ Full SEDOL is B0YBKJ7 Enter the first 6 digits of a SEDOL: 406566 Full SEDOL is 4065663 Enter the first 6 digits of a SEDOL: B0YBLH Full SEDOL is B0YBLH2 Enter the first 6 digits of a SEDOL: 228276 Full SEDOL is 2282765 Enter the first 6 digits of a SEDOL: B0YBKL Full SEDOL is B0YBKL9 Enter the first 6 digits of a SEDOL: 557910 Full SEDOL is 5579107 Enter the first 6 digits of a SEDOL: B0YBKR Full SEDOL is B0YBKR5 Enter the first 6 digits of a SEDOL: 585284 Full SEDOL is 5852842 Enter the first 6 digits of a SEDOL: B0YBKT Full SEDOL is B0YBKT7 Enter the first 6 digits of a SEDOL: B00030 Full SEDOL is B000300 Enter the first 6 digits of a SEDOL: Booo3o INVALID Enter the first 6 digits of a SEDOL: B123456 INVALID
OCaml
<lang ocaml>let char2value c =
assert (not (String.contains "AEIOU" c)); match c with '0'..'9' -> int_of_char c - int_of_char '0' | 'A'..'Z' -> int_of_char c - int_of_char 'A' + 10
let sedolweight = [1;3;1;7;3;9]
let explode s =
let result = ref [] in String.iter (fun c -> result := c :: !result) s; List.rev !result
let checksum sedol =
let tmp = List.fold_left2 (fun sum ch weight -> sum + char2value ch * weight) 0 (explode sedol) sedolweight in string_of_int ((10 - (tmp mod 10)) mod 10)
List.iter (fun sedol -> print_endline (sedol ^ checksum sedol))
[ "710889"; "B0YBKJ"; "406566"; "B0YBLH"; "228276"; "B0YBKL"; "557910"; "B0YBKR"; "585284"; "B0YBKT" ]</lang>
Perl
This program reads from standard input. <lang perl>use List::Util qw(sum); use POSIX qw(strtol);
sub zip(&\@\@) {
my $f = shift; my @a = @{shift()}; my @b = @{shift()}; my @result; push(@result, $f->(shift @a, shift @b)) while @a && @b; return @result;
}
my @weights = (1, 3, 1, 7, 3, 9); sub sedol($) {
my $s = shift; $s =~ /[AEIOU]/ and die "No vowels"; my @vs = map {(strtol $_, 36)[0]} split //, $s; my $checksum = sum (zip {$_[0] * $_[1]} @vs, @weights); my $check_digit = (10 - $checksum % 10) % 10; return $s . $check_digit;
}
while (<>) {
chomp; print sedol($_), "\n";
}</lang>
Perl 6
Note: Change %base36 and @weights from `my` to `constant` when Rakudo implements them. <lang perl6>sub sedol( Str $s ) {
die 'No vowels allowed' if $s ~~ /<[AEIOU]>/; die 'Invalid format' if $s !~~ /^ <[0..9B..DF..HJ..NP..TV..Z]>**6 $ /;
my %base36 = ( 0..9, 'A'..'Z' ) Z ( ^36 ); my @weights = 1, 3, 1, 7, 3, 9;
my @vs = %base36{ $s.comb }; my $checksum = [+] @vs Z* @weights; my $check_digit = (10 - $checksum % 10) % 10; return $s ~ $check_digit;
}
say sedol($_) for <
710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030
>;</lang>
PHP
<lang php>function char2value($c) {
assert(stripos('AEIOU', $c) === FALSE); return intval($c, 36);
}
$sedolweight = array(1,3,1,7,3,9);
function checksum($sedol) {
global $sedolweight; $tmp = array_sum(array_map(create_function('$ch, $weight', 'return char2value($ch) * $weight;'), str_split($sedol), $sedolweight) ); return strval((10 - ($tmp % 10)) % 10);
}
foreach (array('710889',
'B0YBKJ', '406566', 'B0YBLH', '228276', 'B0YBKL', '557910', 'B0YBKR', '585284', 'B0YBKT') as $sedol) echo $sedol, checksum($sedol), "\n";</lang>
PicoLisp
<lang PicoLisp>(de sedol (Str)
(pack Str (char (+ `(char "0") (% (- 10 (% (sum '((W C) (cond ((>= "9" C "0") (* W (- (char C) `(char "0"))) ) ((>= "Z" (setq C (uppc C)) "A") (* W (+ 10 (- (char C) `(char "A")))) ) ) ) (1 3 1 7 3 9) (chop Str) ) 10 ) ) 10 ) ) ) ) )
(for S '("710889" "B0YBKJ" "406566" "B0YBLH" "228276" "B0YBKL" "557910" "B0YBKR" "585284" "B0YBKT" "B00030")
(prinl (sedol S)) )</lang>
PureBasic
<lang PureBasic>Procedure.s SEDOLs(rawstring$)
Protected i, j, sum, c, m For i=1 To Len(rawstring$) c=Asc(Mid(rawstring$,i,1)) Select c Case Asc("0") To Asc("9") j=Val(Mid(rawstring$,i,1)) Default j=c-Asc("A") EndSelect Select i Case 1, 3, 7: m=1 Case 2, 5: m=3 Case 4: m=7 Default: m=9 EndSelect sum+j*m Next sum=(10-(sum%10))%10 ProcedureReturn rawstring$+Str(sum)
EndProcedure
Define result$, i Restore Tests For i=0 To 10
Read.s SEDOL$ result$+SEDOLs(SEDOL$) If i%2 result$+#CRLF$ ElseIf i<10 result$+", " EndIf
Next MessageRequester("SEDOLs","Result"+#CRLF$+result$)
DataSection
Tests: Data.s "710889","B0YBKJ","406566","B0YBLH","228276" Data.s "B0YBKL","557910","B0YBKR","585284","B0YBKT","B00030"
EndDataSection</lang>
Python
<lang python>def char2value(c):
assert c not in 'AEIOU', "No vowels" return int(c, 36)
sedolweight = [1,3,1,7,3,9]
def checksum(sedol):
tmp = sum(map(lambda ch, weight: char2value(ch) * weight, sedol, sedolweight) ) return str((10 - (tmp % 10)) % 10)
for sedol in
710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT .split(): print sedol + checksum(sedol)</lang>
R
<lang r># Read in data from text connection datalines <- readLines(tc <- textConnection("710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT")); close(tc)
- Check data valid
checkSedol <- function(datalines) {
ok <- grep("^[[:digit:][:upper:]]{6}$", datalines) if(length(ok) < length(datalines)) { stop("there are invalid lines") }
} checkSedol(datalines)
- Append check digit
appendCheckDigit <- function(x) {
if(length(x) > 1) return(sapply(x, appendCheckDigit)) ascii <- as.integer(charToRaw(x)) scores <- ifelse(ascii < 65, ascii - 48, ascii - 55) weights <- c(1, 3, 1, 7, 3, 9) chkdig <- (10 - sum(scores * weights) %% 10) %% 10 paste(x, as.character(chkdig), sep="")
} withchkdig <- appendCheckDigit(datalines)
- Print in format requested
writeLines(withchkdig)</lang>
REXX
<lang rexx> /*REXX program computes the check (last) digit for 6 or 7 char SEDOLs.*/
/*if the SEDOL is 6 characters, a */ /*check digit is added. */
/*if the SEDOL is 7 characters, a */ /*check digit is created and it is*/ /*verified that it's equal to the */ /*check digit already on the SEDOL*/
@.=
parse arg @.1 . /*allow user-specified SEDOL. */ if @.1== then do /*if none, then assume 11 defaults*/
@.1 ='710889' @.2 ='B0YBKJ' @.3 ='406566' @.4 ='B0YBLH' @.5 ='228276' @.6 ='B0YBKL' @.7 ='557910' @.8 ='B0YBKR' @.9 ='585284' @.10='B0YBKT' @.11='B00030' end
@abc='abcdefghijklmnopqrstuvwxyz' /*the alphabet, lower case. */ @abcU=@abc; upper @abcU /* " " upper case. */ alphaDigs='0123456789'@abcU /*legal chars, and then some. */ allowable=translate(alphaDigs,,'AEIOU') /*now, remove the vowels. */ allowable=space(allowable,0) /*now, remove the blanks. */ weights='1317391' /*various weights for SEDOL chars*/
/*an alternative would be to use:*/ /* weights='1 3 1 7 3 9 1' if */ /*any weights were greater than 9*/
do j=1 while @.j\== /*process each specified SEDOL. */ sedol=@.j; upper sedol /*uppercase it, just in case. */ L=length(sedol) if L<6 | L>7 then call ser "SEDOL isn't a valid length" if left(sedol,1)==9 then call swa 'SEDOL is reserved for end user allocation' _=verify(sedol,allowable) if _\==0 then call ser 'illegal character in SEDOL:' substr(sedol,_,1) sum=0 /*checkDigit sum (so far). */
do k=1 for 6 /*process each character in SEDOL*/ sum=sum+(pos(substr(sedol,k,1),alphaDigs)-1)*substr(weights,k,1) end
chkDig=(10-sum//10)//10 r=right(sedol,1) if L==7 & chkDig\==r then call ser sedol,'invalid check digit:' r say 'SEDOL:' left(sedol,9) 'SEDOL + check digit:' left(sedol,6)chkDig end /*j*/
exit
/*─────────────────────────────────────subroutines──────────────────────*/ sed: say; say 'SEDOL:' sedol; say; return ser: say; say '*** error! ***'; say; say arg(1); call sed; exit 13 swa: say; say '*** warning! ***' arg(1); say; return </lang> Output when using the defaults:
SEDOL: 710889 SEDOL + check digit: 7108899 SEDOL: B0YBKJ SEDOL + check digit: B0YBKJ7 SEDOL: 406566 SEDOL + check digit: 4065663 SEDOL: B0YBLH SEDOL + check digit: B0YBLH2 SEDOL: 228276 SEDOL + check digit: 2282765 SEDOL: B0YBKL SEDOL + check digit: B0YBKL9 SEDOL: 557910 SEDOL + check digit: 5579107 SEDOL: B0YBKR SEDOL + check digit: B0YBKR5 SEDOL: 585284 SEDOL + check digit: 5852842 SEDOL: B0YBKT SEDOL + check digit: B0YBKT7 SEDOL: B00030 SEDOL + check digit: B000300
Ruby
<lang ruby>def char2value(c)
raise "No vowels" if 'AEIOU'.include?(c) c.to_i(36)
end
Sedolweight = [1,3,1,7,3,9]
def checksum(sedol)
tmp = sedol.split().zip(Sedolweight).map { |ch, weight| char2value(ch) * weight }.inject(0) { |sum, x| sum + x } ((10 - (tmp % 10)) % 10).to_s
end
for sedol in %w{
710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT } puts sedol + checksum(sedol)
end</lang>
Scala
<lang scala>class SEDOL(s: String) {
require(s.size == 6 || s.size == 7, "SEDOL length must be 6 or 7 characters") require(s.size == 6 || s(6).asDigit == chksum, "Incorrect SEDOL checksum") require(s forall (c => !("aeiou" contains c.toLower)), "Vowels not allowed in SEDOL") def chksum = 10 - ((s zip List(1, 3, 1, 7, 3, 9) map { case (c, w) => c.asDigit * w } sum) % 10) override def toString = s.take(6) + chksum
}</lang>
Test cases:
scala> """710889 | B0YBKJ | 406566 | B0YBLH | 228276 | B0YBKL | 557910 | B0YBKR | 585284 | B0YBKT""".lines.map(_.trim).foreach(s => println(new SEDOL(s))) 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7
Validations:
scala> new SEDOL("12") java.lang.IllegalArgumentException: requirement failed: SEDOL length must be 6 or 7 characters scala> new SEDOL("7108890") java.lang.IllegalArgumentException: requirement failed: Incorrect SEDOL checksum scala> new SEDOL("71088A") java.lang.IllegalArgumentException: requirement failed: Vowels not allowed in SEDOL
Seed7
<lang seed7>$ include "seed7_05.s7i";
const func char: sedolCheckDigit (in string: sedol) is func
result var char: checkDigit is ' '; local const array integer: weight is [] (1, 3, 1, 7, 3, 9); var char: ch is ' '; var integer: index is 0; var integer: item is 0; var integer: sum is 0; begin for ch key index range sedol do case ch of when {'0' .. '9'}: item := ord(ch) - ord('0'); when {'A' .. 'Z'} - {'A', 'E', 'I', 'O', 'U'}: item := ord(ch) - ord('A') + 10; otherwise: raise RANGE_ERROR; end case; sum +:= item * weight[index]; end for; checkDigit := chr(-sum mod 10 + ord('0')); end func;
const proc: main is func
local var string: sedol is ""; begin for sedol range [] ("710889", "B0YBKJ", "406566", "B0YBLH", "228276", "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT", "B00030") do writeln(sedol <& sedolCheckDigit(sedol)); end for; end func;</lang>
Output:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300
Smalltalk
<lang smalltalk>String extend [
includesAnyOf: aSet [ aSet do: [ :e | (self includes: e) ifTrue: [ ^true ] ]. ^false ]
].</lang>
<lang smalltalk>Object subclass: SEDOL [
|weight charList|
initialize [ weight := Array from: { 1. 3. 1. 7. 3. 9 }. charList := ('ABCDEFGHIJKLMNOPQRSTUVWXYZ' asOrderedCollection) collect: [ :c | ('AEIOU' includes: c) ifTrue: [ nil ] ifFalse: [ c ] ]. ]
SEDOL class >> new [ ^ (self basicNew) initialize ]
"to be considered private" blindCheckDigit: aSEDOL [ |sum| sum := 0. aSEDOL keysAndValuesDo: [ :i :c | ('0123456789' includes: c) ifTrue: [ sum := sum + ((weight at: i) * (Number readFrom: (c asString readStream))). ] ifFalse: [ sum := sum + (((charList indexOf: c) + 9) * (weight at: i)) ] ]. ^ ((10 - (sum rem: 10)) rem: 10) displayString ]
checked: aSEDOL [ (aSEDOL size < 6) | (aSEDOL size > 7) | (aSEDOL asUppercase includesAnyOf: 'AEIOU' asSet ) ifTrue: [ SystemExceptions.InvalidArgument signalOn: aSEDOL reason: 'Not a valid SEDOL' ] ifFalse: [ |t| t := aSEDOL copyFrom: 1 to: 6. ^ t , (self blindCheckDigit: t) ] ]
].</lang>
<lang smalltalk>|sedol| sedol := SEDOL new. { '710889'.
'B0YBKJ'. '406566'. 'B0YBLH'. '228276'. 'B0YBKL'. '557910'. 'B0YBKR'. '585284'. 'B0YBKT' } do: [ :c | (sedol checked: c) displayNl ]</lang>
Standard ML
<lang sml>fun char2value c =
if List.exists (fn x => x = c) (explode "AEIOU") then raise Fail "no vowels" else if Char.isDigit c then ord c - ord #"0" else if Char.isUpper c then ord c - ord #"A" + 10 else raise Match
val sedolweight = [1,3,1,7,3,9]
fun checksum sedol = let
val tmp = ListPair.foldlEq (fn (ch, weight, sum) => sum + char2value ch * weight) 0 (explode sedol, sedolweight)
in
Int.toString ((10 - (tmp mod 10)) mod 10)
end
app (fn sedol => print (sedol ^ checksum sedol ^ "\n"))
[ "710889", "B0YBKJ", "406566", "B0YBLH", "228276", "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT" ];</lang>
Tcl
<lang tcl>namespace eval sedol {
variable chars {0 1 2 3 4 5 6 7 8 9 "" B C D "" F G H "" J K L M N "" P Q R S T "" V W X Y Z} variable weight {1 3 1 7 3 9 1}
proc checksum {alnum6} { variable chars variable weight set sum 0 set col 0 foreach char [split [string toupper [string range $alnum6 0 5]] ""] { if {[set idx [lsearch -exact $chars $char]] == -1} { error "invalid character: $char" } incr sum [expr {$idx * [lindex $weight $col]}] incr col } return [expr {(10 - ($sum % 10)) % 10}] } proc valid {alnum7} { expr {[checksum [string range $alnum7 0 5]] == [string index $alnum7 6]} }
}
proc assert {condition {message "Assertion failed!"}} {
if { ! [uplevel 1 [list expr $condition]]} { return -code error $message }
}
set codes {710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT} set answers {7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7}
foreach code $codes answer $answers {
set sedol "${code}[sedol::checksum $code]" assert {$sedol eq $answer} "assertion failed: $sedol ne $answer" puts $sedol
}</lang>
T-SQL
SQL Server transact-SQL implementation. Compatible with all versions from 6.5 to 2008 Returns empty string if invalid
examples: print dbo.fn_CheckSEDOL('710889') print dbo.fn_CheckSEDOL('B0YBKJ') print dbo.fn_CheckSEDOL('406566') print dbo.fn_CheckSEDOL('B0YBLH') print dbo.fn_CheckSEDOL('228276') print dbo.fn_CheckSEDOL('B0YBKL') print dbo.fn_CheckSEDOL('557910') print dbo.fn_CheckSEDOL('B0YBKR') print dbo.fn_CheckSEDOL('585284') print dbo.fn_CheckSEDOL('B0YBKT') print dbo.fn_CheckSEDOL('B00030')
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300
<lang tsql>
CREATE FUNCTION [dbo].[fn_CheckSEDOL] ( @SEDOL varchar(50) ) RETURNS varchar(7) AS BEGIN declare @true bit = 1, @false bit = 0, @isSEDOL bit, @sedol_weights varchar(6) ='131739', @sedol_len int = LEN(@SEDOL), @sum int = 0
if ((@sedol_len = 6))
begin
select @SEDOL = UPPER(@SEDOL)
Declare @vowels varchar(5) = 'AEIOU',
@letters varchar(21) = 'BCDFGHJKLMNPQRSTVWXYZ',
@i int=1,
@isStillGood bit = @true,
@char char = ,
@weighting int =0
select @isSEDOL = @false
while ((@i < 7) and (@isStillGood = @true)) begin select @char = SUBSTRING(@SEDOL,@i,1), @weighting = CONVERT (INT,SUBSTRING(@sedol_weights, @i, 1)) if (CHARINDEX(@char, @vowels) > 0) -- no vowels please begin select @isStillGood=@false end else begin if (ISNUMERIC(@char) = @true) -- is a number begin select @sum = @sum + (ASCII(@char) - 48) * @weighting end else if (CHARINDEX(@char, @letters) > 0) -- test for the rest of the alphabet begin select @isStillGood=@false end else begin select @sum = @sum + (ASCII(@char) - 55) * @weighting end end select @i = @i +1 end -- of while loop if (@isStillGood = @true) begin declare @checksum int = (10 - (@sum%10))%10 select @SEDOL = @SEDOL + CONVERT(CHAR,@checksum) end end else begin select @SEDOL = end -- Return the result of the function RETURN @SEDOL END
</lang>
TUSCRIPT
<lang tuscript> $$ MODE TUSCRIPT check="1'3'1'7'3'9" values="123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" value=STRINGS (values,":<%:") BUILD r_TABLE/or illegal=":A:E:I:O:U:" LOOP input="710889'B0YBKJ'406566'B0YBLH'228276'B0YBKL'557910'B0YBKR'585284'B0YBKT'BOYAKT'B00030",sum=""
IF (input.ma.illegal) THEN PRINT/ERROR input, " illegal" CYCLE ENDIF strings=STRINGS (input,":<%:") LOOP d,nr=strings c=SELECT (check,#d) IF (nr!='digits') nr=FILTER_INDEX (value,":{nr}:",-) x=nr*c, sum=APPEND(sum,x) ENDLOOP endsum=SUM(sum), checksum=10-(endsum%10) IF (checksum==10) checksum=0 PRINT input, " checkdigit: ", checksum
ENDLOOP </lang> Output:
710889 checkdigit: 9 B0YBKJ checkdigit: 7 406566 checkdigit: 3 B0YBLH checkdigit: 2 228276 checkdigit: 5 B0YBKL checkdigit: 9 557910 checkdigit: 7 B0YBKR checkdigit: 5 585284 checkdigit: 2 B0YBKT checkdigit: 7 @@@@@@@@ BOYAKT illegal B00030 checkdigit: 0
Ursala
The straightforward approach closely follows the published specification, using a table-driven finite map (charval) from characters to numbers, and calculating the inner product as a cumulative sum of the weight vector zipped with the product function to the list of character values.
<lang Ursala>#import std
- import nat
alphabet = digits-- ~=`A-~r letters weights = <1,3,1,7,3,9> charval = -:@rlXS num alphabet iprod = sum:-0+ product*p/weights+ charval* checksum = difference/10+ remainder\10+ iprod</lang>
An optimization following the J solution avoids a run-time subtraction by complementing the coefficients at compile time using these definitions in place of those above. <lang Ursala>weights = difference/*10 <1,3,1,7,3,9> checksum = remainder\10+ iprod</lang>
A further performance improvement subsumes the character value lookup and multiplcation table within the same finite map in the version shown below.
<lang Ursala>lookup = -: (^/~& product^|/~& charval)*lsPrK0/weights alphabet iprod = sum:-0+ lookup*p/weights</lang>
To optimize further, we can build a separate smaller multiplication table for each coefficient, letting the coefficient be hard coded and allowing faster lookups. The zipwith operation (*p) is also avoided by having each map index directly into the input list.
<lang Ursala>lookups = (-:+ * ^/~&l product^|/charval ~&)* *-* -*weights alphabet iprod = sum:-0+ gang +^|(~&,~)*lNrXXK9 ^(~&,&h!)* lookups</lang> Here is a test program. <lang Ursala>#show+
examples = ^T(~&,~&h+ %nP+ checksum)*t
-[ 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT]-</lang> output:
7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7