topic Re: Add header to csv file in Python Questions

Add header to csv file

jaykapalczynski — Sat, 11 Dec 2021 15:03:34 GMT

I am creating a csv file via the SearchCursor. This Works great....although I am not getting the field names in there. I went about this 2 ways. I have tried a ton of forums but just cant seem to get the right syntax to create this ONLY once and when I bring it into Excel it has a header for each field.

Any thoughts?

I add the headers IN the "for row in cursor"

This adds them BUT it creates a set of headers for each record imported

with arcpy.da.SearchCursor(fc, [var_region_1 ,var_county_1,var_ramp_1], where_clause=expression) as cursor:
   for row in cursor:
       zval = str('{0},{1},{2}'.format(row[0],row[1],row[2]))
       headers = ['region_1','county_1','ramp_1']
       outFile.write('\t'.join(headers) + '\n')        
       outFile.write(zval + "%s\n")

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Add headers BEFORE the "for row in cursor"

This adds them but when I bring into excel they are all crammed into the first box, not spread out for each field.

headers = ['region_1','county_1','ramp_1']
outFile.write('\t'.join(headers) + '\n')

with arcpy.da.SearchCursor(fc, [var_region_1 ,var_county_1,var_ramp_1], where_clause=expression) as cursor:
   for row in cursor:
      zval = str('{0},{1},{2}'.format(row[0],row[1],row[2]))
      outFile.write(zval + "%s\n")

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Re: Add header to csv file

JoshuaBixby — Tue, 22 Nov 2016 19:51:27 GMT

You are creating a CSV, which is comma delimited, but you are inserting tabs between your headers, so they are all getting treated as a header for a single field/column.

Re: Add header to csv file

jaykapalczynski — Tue, 22 Nov 2016 19:52:32 GMT

I got it...answered my own question! Just added , inside the quotes.

headers = ['region_1,','county_1,','ramp_1,']‍

Re: Add header to csv file

jaykapalczynski — Tue, 22 Nov 2016 20:07:31 GMT

I have one last issue. I have many many fields...when I write the header in it writes to the second line when I bring the csv into excel.

BUT the data that I am writing to the same csv file does not. The individual records are all on the same line.

Why is this? Can I specify to not return to the 2nd line ?

Re: Add header to csv file

JoshuaBixby — Tue, 22 Nov 2016 20:08:11 GMT

Although that works, it isn't very Pythonic. Your original code can be modified slightly to make it work with existing header format:

outFile.write(','.join(headers) + '\n')‍

Re: Add header to csv file

jaykapalczynski — Tue, 22 Nov 2016 20:22:26 GMT

I changed to that...but when using the below it writes header values to the 1st and 2nd line.

NOTE: I have 78 fields. The header line below is just showing 3. Might be hitting a limit in Excel from a CSV file?

headers = ["region_1,county_1,ramp_1,date,"]

Re: Add header to csv file

JoshuaBixby — Sat, 11 Dec 2021 15:03:36 GMT

What does this produce, using either 3 or 78? (Note, commas outside of strings)

headers = ['region_1', 'county_1', 'ramp_1']
outFile.write(','.join(headers) + '\n')‍‍

Re: Add header to csv file

jaykapalczynski — Tue, 22 Nov 2016 20:38:21 GMT

When i use 3 it places them in the correct location.

When I use all 78 it gets to a point it cuts off the text between the ' '

It then throws the rest of what go cut off to the next line and then all the others that follow are placed in the proper locations albeit in the 2nd row.

It appears that I am hitting some sort of character limit in the CSV as it returns to the next line for the header....too many characters?

See attached csv and excel file outputs.

Re: Add header to csv file

jaykapalczynski — Tue, 22 Nov 2016 20:51:48 GMT

I think I am running into this issue....researching now...

Maximum length of CSV file

Re: Add header to csv file

JoshuaBixby — Tue, 22 Nov 2016 20:52:21 GMT

When I open the CSV, everything looks fine. When I open the CSV directly in Excel, it displays fine. When I open your XLS, I see your issue. What version of Excel are you using? I am looking at the CSV using Excel 2013?

Re: Add header to csv file

jaykapalczynski — Tue, 22 Nov 2016 20:56:14 GMT

Excel 2010...

Yea something weird is going on...If I copy the created .csv file from my server to my PC, then go File>open (not drag and drop it woks fine). Drag and drop it carries to the next line. But that only works once....then it gets all screwed up again...Very puzzled...going to try and decrease the characters being used in the header to see if that helps.

Re: Add header to csv file

jaykapalczynski — Tue, 22 Nov 2016 21:03:04 GMT

I stripped down a bunch of characters from the Header...it appears to be working now...definitely think I was hitting some sort of Character limit...I thank you very much for you help...spent way to long on this already...seems to be working...just watch how many characters I have from now on....