Write multiple lines to text file with many %s in string

Question

I am trying to write many lines to a text file but it contains many dates for each line.

The code looks like this:

directory = 'C:\SPAN'
with open(os.path.join(directory, 'SPANscript.txt'), 'w') as OPATH:
    OPATH.writelines([r'Load C:\SPAN\RiskFiles\%s\SGX.%s.s.pa2'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y%m%d")),
                      r'Load C:\SPAN\RiskFiles\%s\cfe.%s.s.pa2'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y%m%d")), 
                      r'Load C:\SPAN\RiskFiles\%s\cme.%s.s.pa2'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y%m%d")), 
                      r'Load C:\SPAN\RiskFiles\%s\hkex.%s.s.pa2'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y%m%d")),
                      r'Load C:\SPAN\RiskFiles\%s\Jsc%s_1700.pa2'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y%m%d")), 
                      r'Load C:\SPAN\Positions\%s\CME_Span_pos_%s.pos'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y-%m-%d")),
                      r'Load C:\SPAN\Positions\%s\HKFE_Span_pos_%s.pos'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y-%m-%d")),
                      r'Load C:\SPAN\Positions\%s\OSE_Span_pos_%s.pos'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y-%m-%d")),
                      r'Load C:\SPAN\Positions\%s\SGX_Span_pos_%s.pos'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y-%m-%d")),
                      r'Load C:\SPAN\Positions\%s\XCME_Span_pos_%s.pos'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y-%m-%d")),
                      r'Load C:\SPAN\Positions\%s\XNYM_Span_pos_%s.pos'% (rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y-%m-%d")),
                      'Calc',
                      r'SaveCalcSummary C:\SPAN\Reports\%s\%s.csv' %(rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y%m%d")),
                      r'Save C:\SPAN\Reports\%s\%s.xml' %(rundate.strftime("%Y-%m-%d"),rundate.strftime("%Y%m%d")),
                      r'LogSave C:\SPAN\Reports\%s\logtest.txt'%rundate.strftime("%Y-%m-%d")])

I would like to make it neater. Saw this post: Python - multiple %s string, but where do i put the format portion? at each line or can i put it outside?

Which version of Python do you have?

iz_
– iz_

2019-01-25 03:37:56 +00:00
Commented Jan 25, 2019 at 3:37 — iz_
– iz_, Commented Jan 25, 2019 at 3:37
I am using Spyder and version 2.7.9

lakshmen
– lakshmen

2019-01-25 03:38:32 +00:00
Commented Jan 25, 2019 at 3:38 — lakshmen
– lakshmen, Commented Jan 25, 2019 at 3:38

iz_ · Accepted Answer · 2019-01-25 03:46:45Z

0

I would recommend using str.format instead of old-style formatting.

directory = r'C:\SPAN'

names = [
    r'Load C:\SPAN\RiskFiles\%s\SGX.%s.s.pa2',
    r'Load C:\SPAN\RiskFiles\%s\cfe.%s.s.pa2', 
    r'Load C:\SPAN\RiskFiles\%s\cme.%s.s.pa2', 
    r'Load C:\SPAN\RiskFiles\%s\hkex.%s.s.pa2',
    r'Load C:\SPAN\RiskFiles\%s\Jsc%s_1700.pa2', 
    r'Load C:\SPAN\Positions\%s\CME_Span_pos_%s.pos',
    r'Load C:\SPAN\Positions\%s\HKFE_Span_pos_%s.pos',
    r'Load C:\SPAN\Positions\%s\OSE_Span_pos_%s.pos',
    r'Load C:\SPAN\Positions\%s\SGX_Span_pos_%s.pos',
    r'Load C:\SPAN\Positions\%s\XCME_Span_pos_%s.pos',
    r'Load C:\SPAN\Positions\%s\XNYM_Span_pos_%s.pos',
    'Calc',
    r'SaveCalcSummary C:\SPAN\Reports\%s\%s.csv',
    r'Save C:\SPAN\Reports\%s\%s.xml',
    r'LogSave C:\SPAN\Reports\%s\logtest.txt'
]
with open(os.path.join(directory, 'SPANscript.txt'), 'w') as OPATH:
    OPATH.writelines(name.replace('%s', '{0}').format(rundate.strftime("%Y-%m-%d")) for name in names)

Of course, if you could manually modify your file names to have {0} instead of %s, you could ditch the .replace('%s', '{0}').

answered Jan 25, 2019 at 3:46

iz_

16.7k4 gold badges29 silver badges43 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

zwer Over a year ago

Word of caution: file.writelines() won't add new lines at the end of each element in the sequence despite what its name might suggest. It's an example of a bad API but the rationale was to have it as a counterpart to file.readlines() which does the opposite and keeps the EOL character(s) so that the result can be used directly in file.writelines().

zwer Over a year ago

Also, it might be a good idea to store rundate.strftime('%Y-%m-%d') outside of the loop and just reuse it instead of executing it for each line.

Selcuk · Accepted Answer · 2019-01-25 03:46:47Z

0

You can use a list comprehension here. For example

...
lines = [
    r'Load C:\SPAN\RiskFiles\%s\SGX.%s.s.pa2', 
    r'Load C:\SPAN\RiskFiles\%s\cfe.%s.s.pa2',
    ...]
formatted_date = rundate.strftime("%Y-%m-%d")
OPATH.writelines([line % (formatted_date, formatted_date) for line in lines])

It is also a good idea to switch to the newer method of string formatting as @Tomothy32 suggested.

answered Jan 25, 2019 at 3:46

Selcuk

60.1k12 gold badges114 silver badges119 bronze badges

Comments

zwer · Accepted Answer · 2019-01-25 04:32:27Z

I don't see the value in adding complexity by introducing loops when you have a preset list of lines to write - all you need is a neater way to inject the date into your template, so something like this:

directory = r'C:\SPAN'
date = rundate.strftime('%Y-%m-%d')

with open(os.path.join(directory, 'SPANscript.txt'), 'w') as f:
    f.write(r'Load C:\SPAN\RiskFiles\{d}\SGX.{d}.s.pa2' '\n'
            r'Load C:\SPAN\RiskFiles\{d}\cfe.{d}.s.pa2' '\n'
            r'Load C:\SPAN\RiskFiles\{d}\cfe.{d}.s.pa2' '\n'
            r'Load C:\SPAN\RiskFiles\{d}\cme.{d}.s.pa2' '\n'
            r'Load C:\SPAN\RiskFiles\{d}\hkex.{d}.s.pa2' '\n'
            r'Load C:\SPAN\RiskFiles\{d}\Jsc{d}_1700.pa2' '\n'
            r'Load C:\SPAN\Positions\{d}\CME_Span_pos_{d}.pos' '\n'
            r'Load C:\SPAN\Positions\{d}\HKFE_Span_pos_{d}.pos' '\n'
            r'Load C:\SPAN\Positions\{d}\OSE_Span_pos_{d}.pos' '\n'
            r'Load C:\SPAN\Positions\{d}\SGX_Span_pos_{d}.pos' '\n'
            r'Load C:\SPAN\Positions\{d}\XCME_Span_pos_{d}.pos' '\n'
            r'Load C:\SPAN\Positions\{d}\XNYM_Span_pos_{d}.pos' '\n'
            'Calc\n'
            r'SaveCalcSummary C:\SPAN\Reports\{d}\{d}.csv' '\n'
            r'Save C:\SPAN\Reports\{d}\{d}.xml' '\n'
            r'LogSave C:\SPAN\Reports\{d}\logtest.txt'.format(d=date))

should be more than enough, plus it will handle newlines properly unlike file.writelines() (see my comment to @Tomothy32's answer).

Collectives™ on Stack Overflow

Write multiple lines to text file with many %s in string

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related