Python, DictReader, DictWriter

Because I can never, ever, remember exactly how to code these. Example of both, basic.

data_list = []

with open(input_file, 'rU') as f:
  data_file = csv.DictReader(f)
  for line in data_file:
    data_list.append(line) # gets you a list of dicts

the_header = ['h1', 'h2', 'etc'] # column headers, a list of text strings

with open(output_file, 'w') as f:
  file_writer = csv.DictWriter(f, fieldnames=the_header)
  file_writer.writeheader()
  for line in data_list:
     file_writer.writerow(line)

Here I am going to experiment linking it as a script-tagged element from Gist via GitHub:

	# Because I always forget exactly how to do these.
	# Note that in function calls the exact code will be a little different (may need additional code).
	# Reading
	data_list = [] # Will be output, list of dicts.
	with open(input_file, 'rU') as f:
	data_file = csv.DictReader(f)
	for line in data_file:
	data_list.append(line) # Gets you a list of dicts.
	# Writing
	the_header = ['h1', 'h2', 'etc'] # Your column headers, a list of text strings. These are placeholders.
	with open(output_file, 'w') as f: # Don't forget your output file has to have a location/name.
	file_writer = csv.DictWriter(f, fieldnames=the_header)
	file_writer.writeheader()
	for line in data_list: # data_list is the list of dicts you are writing.
	file_writer.writerow(line)
	# Done!

view raw csvDict_read_write.py hosted with ❤ by GitHub