python - Reading a compressed/deflated (csv) file line by line -


this question has answer here:

i'm using following generator iterate through given csv file row row in memory efficient way:

def csvreader(file):     open(file, 'rb') csvfile:         reader = csv.reader(csvfile, delimiter=',',quotechar='"')         row in reader:             yield row`

this works , able handle large files incredibly well. csv file of several gigabytes seems no problem @ small virtual machine instance limited ram.

however, when files grow large, disk space becomes problem. csv files seem high compression rates, allows me store files @ fraction of uncompressed size, before can use above code handle file, have decompress/inflate file , run through script.

my question: there way build efficient generator above (given file, yield csv rows array), inflating parts of file, till newline reached, , running through csv reader, without ever having deflate/decompress file whole?

thanks consideration!

try using gzip

just replace with open(file, 'rb') csvfile: with gzip.open(file, 'rb') csvfile: , add import gzip @ top of script.

see this question more


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