I am attempting to read a CSV file, edit a specific entry, then write back to disk. I am having trouble writing back to disk. I used split to separate fields and change. I can print the changes, but now I cannot write them back to the file. Can someone show me a quick simple example? (for simplicity I am using a small data file with 10 entries, seperated with commas, no headers)
Thank you
3  2826  bvdet 2,851
Recognized Expert Moderator Specialist
Let's say you read the csv file into a list of lists named dataList and you want to change the last element in the first line. - import csv
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dataList = [0.0, 5.0, 10.0, 15.0, 20.0, 25.0, 30.0, 35.0, 40.0, 45.0, 50.0],\
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[0.0, 5.0, 10.0, 15.0, 20.0, 25.0, 30.0, 30.0, 30.0, 30.0, 30.0], \
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[0.0, 0.0, 0.0, 5.0, 10.0, 15.0, 20.0, 25.0, 30.0, 30.0, 30.0],\
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[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 5.0, 10.0, 15.0, 20.0, 25.0]
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dataList[0][-1] = "XXXX"
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fn = r'D:\tmp\some.csv'
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f = open(fn, 'wb')
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w = csv.writer(f)
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w.writerows(dataList)
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f.close()
Ok good. How would I allow user input to choose which entry?
bvdet 2,851
Recognized Expert Moderator Specialist
That depends on what you want. You could prompt the user using built-in function raw_input (input in Python 3.x) for the line and column to change and the new value, or you could build a GUI with Tkinter or other GUI toolkit with rows and columns of widgets where the user could edit whatever he wants.
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