Align columns: Difference between revisions
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Further,$allow$for$each$word$in$a$column$to$be$either$left$ |
Further,$allow$for$each$word$in$a$column$to$be$either$left$ |
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justified,$right$justified,$or$center$justified$within$its$column.</pre> |
justified,$right$justified,$or$center$justified$within$its$column.</pre> |
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Note that: |
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# The example input texts lines may, or may not, have trailing dollar characters. |
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# Consecutive space characters produced adjacent to the end of lines is insignificant for the purposes of the task. |
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=={{header|Ada}}== |
=={{header|Ada}}== |
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{{libheader|Simple components for Ada}} |
{{libheader|Simple components for Ada}} |
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Revision as of 03:50, 2 December 2008
You are encouraged to solve this task according to the task description, using any language you may know.
Given a text file of many lines, where fields within a line are delineated by a single 'dollar' character, write a program that aligns each column of fields by ensuring that words in each column are separated by at least one space. Further, allow for each word in a column to be either left justified, right justified, or center justified within its column.
Use the following text to test your programs:
Given$a$text$file$of$many$lines,$where$fields$within$a$line$ are$delineated$by$a$single$'dollar'$character,$write$a$program that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$ column$are$separated$by$at$least$one$space. Further,$allow$for$each$word$in$a$column$to$be$either$left$ justified,$right$justified,$or$center$justified$within$its$column.
Note that:
- The example input texts lines may, or may not, have trailing dollar characters.
- Consecutive space characters produced adjacent to the end of lines is insignificant for the purposes of the task.
Ada
<ada> with Ada.Characters.Latin_1; use Ada.Characters.Latin_1; with Ada.Text_IO; use Ada.Text_IO; with Strings_Edit; use Strings_Edit;
procedure Column_Aligner is
Text : constant String :=
"Given$a$text$file$of$many$lines,$where$fields$within$a$line$" & NUL &
"are$delineated$by$a$single$'dollar'$character,$write$a$program" & NUL &
"that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$" & NUL &
"column$are$separated$by$at$least$one$space." & NUL &
"Further,$allow$for$each$word$in$a$column$to$be$either$left$" & NUL &
"justified,$right$justified,$or$center$justified$within$its$column." & NUL;
File : File_Type;
Width : array (1..1_000) of Natural := (others => 0);
Line : String (1..200);
Column : Positive := 1;
Start : Positive := 1;
Pointer : Positive;
begin
Create (File, Out_File, "columned.txt");
-- Determining the widths of columns
for I in Text'Range loop
case Text (I) is
when '$' | NUL =>
Width (Column) := Natural'Max (Width (Column), I - Start + 1);
Start := I + 1;
if Text (I) = NUL then
Column := 1;
else
Column := Column + 1;
end if;
when others =>
null;
end case;
end loop;
-- Formatting
for Align in Alignment loop
Column := 1;
Start := 1;
Pointer := 1;
for I in Text'Range loop
case Text (I) is
when '$' | NUL =>
Put -- Formatted output of a word
( Destination => Line,
Pointer => Pointer,
Value => Text (Start..I - 1),
Field => Width (Column),
Justify => Align
);
Start := I + 1;
if Text (I) = NUL then
Put_Line (File, Line (1..Pointer - 1));
Pointer := 1;
Column := 1;
else
Column := Column + 1;
end if;
when others =>
null;
end case;
end loop;
end loop;
Close (File);
end Column_Aligner; </ada> Formatted file sample:
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.
ALGOL 68
STRING nl = REPR 10;
STRING text in list := "Given$a$text$file$of$many$lines,$where$fields$within$a$line$"+nl+
"are$delineated$by$a$single$'dollar'$character,$write$a$program"+nl+
"that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$"+nl+
"column$are$separated$by$at$least$one$space."+nl+
"Further,$allow$for$each$word$in$a$column$to$be$either$left$"+nl+
"justified,$right$justified,$or$center$justified$within$its$column.";
MODE PAGE = FLEX[0,0]STRING;
PAGE page;
PROC flex page = (PAGE in page, INT row, col)PAGE:(
HEAP FLEX[row, col]STRING out page;
out page[:1 UPB in page, :2 UPB in page] := in page;
FOR r TO row DO
FOR c FROM 2 UPB in page + 1 TO col DO out page[r,c]:="" OD
OD;
FOR r FROM 1 UPB in page + 1 TO row DO
FOR c FROM 1 TO col DO out page[r,c]:="" OD
OD;
out page
);
FILE text in file;
associate(text in file, text in list);
make term(text in file, "$");
on physical file end(text in file, (REF FILE skip)BOOL: stop iteration);
on logical file end(text in file, (REF FILE skip)BOOL: stop iteration);
FOR row DO
on line end(text in file, (REF FILE skip)BOOL: stop iteration);
FOR col DO
STRING tok;
getf(text in file, ($gx$,tok));
IF row > 1 UPB page THEN page := flex page(page, row, 2 UPB page) FI;
IF col > 2 UPB page THEN page := flex page(page, 1 UPB page, col) FI;
page[row,col]:=tok
OD;
stop iteration:
SKIP
OD;
stop iteration:
SKIP;
BEGIN
PROC aligner = (PAGE in page, PROC (STRING,INT)STRING aligner)VOID:(
PAGE page := in page;
[2 UPB page]INT max width;
FOR col TO 2 UPB page DO
INT max len:=0; FOR row TO UPB page DO IF UPB page[row,col]>max len THEN max len:=UPB page[row,col] FI OD;
FOR row TO UPB page DO page[row,col] := aligner(page[row,col], maxlen) OD
OD;
printf(($n(UPB page)(n(2 UPB page -1)(gx)gl)$,page))
);
PROC left = (STRING in, INT len)STRING: in + " "*(len - UPB in),
right = (STRING in, INT len)STRING: " "*(len - UPB in) + in,
centre = (STRING in, INT len)STRING: ( INT pad=len-UPB in; pad%2*" "+ in + (pad-pad%2)*" " );
[]STRUCT(STRING name, PROC(STRING,INT)STRING align) aligners = (("Left",left), ("Left",right), ("Centre",centre));
FOR index TO UPB aligners DO
print((new line, "# ",name OF aligners[index]," Column-aligned output:",new line));
aligner(page, align OF aligners[index])
OD
END
J
In this program the justification is optionally specified by a left argument, and may be specified independently for each column.
colalign=: verb define
'L' colalign y NB. default to left-justify all columns
:
D=. '$' NB. the column delimiter
afD=. ,&.> (#&D&.> @: (D&~: @: {: &.>)) NB. assure final delimiter (verb)
T0=. afD <;._2 y NB. text arranged as lines
T1=. > <;._2&.> T0 NB. as word grid
Alignment=. x, (({:$T1)-#x) # {:x
if. 'C' e. Alignment do.
Colwidths=. >./"2 Sizes=. > #&.>"0 T1
CPad=. ('C'=Alignment)*"1 <.2%~ Sizes -~"1 Colwidths
T2=. T1 ,~&.>"0 CPad #&.>"0 ' ' NB. as center-justify-padded grid
else. T2=. T1 end.
if. doesR=. 'R' e. Alignment do.
whereR=.'R'=Alignment
T3=. (($T2)$whereR)}(,: |.&.>) T2 NB. as right-justify-prepared grid
else. T3=. T2 end.
T4=. >@{."1&.> 1 <@|:;.1 |: T3 NB. as columns
if. doesR do.
T5=. whereR }(,: |."1&.>) T4 NB. as rt-jstfy-completed columns
else. T5=. T4 end.
SP=. <|:,:' '#~#T0 NB. space-column to interleave with text columns
>,"1&.>/ }. ,|: SP,,:T5
)
text=: noun define
Given$a$text$file$of$many$lines,$where$fields$within$a$line$
are$delineated$by$a$single$'dollar'$character,$write$a$program
that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$
column$are$separated$by$at$least$one$space.
Further,$allow$for$each$word$in$a$column$to$be$either$left$
justified,$right$justified,$or$center$justified$within$its$column.
)
Examples of use:
colalign text
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.
'C' colalign text
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.
'RRRRCCCL' colalign text
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.
OCaml
<ocaml>#load "str.cma" open Str
let input = "\ Given$a$text$file$of$many$lines,$where$fields$within$a$line$ are$delineated$by$a$single$'dollar'$character,$write$a$program that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$ column$are$separated$by$at$least$one$space. Further,$allow$for$each$word$in$a$column$to$be$either$left$ justified,$right$justified,$or$center$justified$within$its$column."
let () =
let lines = split (regexp_string "\n") input in
let fields_l = List.map (split (regexp_string "$")) lines in
let fields_l = List.map Array.of_list fields_l in
let n = (* number of columns *)
List.fold_left
(fun n fields -> max n (Array.length fields))
0 fields_l
in
let pads = Array.make n 0 in
List.iter (
(* calculate the max padding for each column *)
Array.iteri
(fun i word -> pads.(i) <- max pads.(i) (String.length word))
) fields_l;
let print f =
List.iter (fun fields ->
Array.iteri (fun i word ->
f word (pads.(i) - (String.length word))
) fields;
print_newline()
) fields_l;
in
(* left column-aligned output *) print (fun word pad -> let spaces = String.make pad ' ' in Printf.printf "%s%s " word spaces);
(* right column-aligned output *) print (fun word pad -> let spaces = String.make pad ' ' in Printf.printf "%s%s " spaces word);
(* center column-aligned output *) print (fun word pad -> let pad1 = pad / 2 in let pad2 = pad - pad1 in let sp1 = String.make pad1 ' ' in let sp2 = String.make pad2 ' ' in Printf.printf "%s%s%s " sp1 word sp2);
- </ocaml>
Python
<python>from StringIO import StringIO
textinfile = Given$a$text$file$of$many$lines,$where$fields$within$a$line$ are$delineated$by$a$single$'dollar'$character,$write$a$program that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$ column$are$separated$by$at$least$one$space. Further,$allow$for$each$word$in$a$column$to$be$either$left$ justified,$right$justified,$or$center$justified$within$its$column.
j2justifier = dict(L=str.ljust, R=str.rjust, C=str.center)
def aligner(infile, justification = 'L'):
\
Justify columns of textual tabular input where the record separator is the newline
and the field separator is a 'dollar' character.
justification can be L, R, or C; (Left, Right, or Centered).
Return the justified output as a string
assert justification in 'LRC', "justification can be L, R, or C; (Left, Right, or Centered)."
justifier = j2justifier[justification]
fieldsbyrecord= [line.strip().split('$') for line in infile]
# pad to same number of fields per record
maxfields = max(len(record) for record in fieldsbyrecord)
fieldsbyrecord = [fields + []*(maxfields - len(fields))
for fields in fieldsbyrecord]
# rotate
fieldsbycolumn = zip(*fieldsbyrecord)
# calculate max fieldwidth per column
colwidths = [max(len(field) for field in column)
for column in fieldsbycolumn]
# pad fields in columns to colwidth with spaces
fieldsbycolumn = [ [justifier(field, width) for field in column]
for width, column in zip(colwidths, fieldsbycolumn) ]
# rotate again
fieldsbyrecord = zip(*fieldsbycolumn)
return "\n".join( " ".join(record) for record in fieldsbyrecord)
for align in 'Left Right Center'.split():
infile = StringIO(textinfile) print "\n# %s Column-aligned output:" % align print aligner(infile, align[0])</python>
Example output:
# Left Column-aligned output:
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.
# Right Column-aligned output:
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.
# Center Column-aligned output:
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, or center justified within its column.