Align columns
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.
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.