🔒 🔒 csv reader

[misty compass]

filename = 'SJOB11251_diann_search_DIANN_report.stats_3.0_fix.csv'
with open(filename) as f:
    reader = csv.reader(f)
    header_row = next(reader)

    # Get filenames and peptides/proteins from this file.
    filenames, proteins, peptides = [], [], []
    for row in reader:
        filename = str(row[0][0:8])
        peptide = int(row[1])
        protein = int(row[2])
        filenames.append(filename)
        peptides.append(peptide)
        proteins.append(protein)

why do i need the "header_row = next(reader)" line? it makes my code fail if i remove it even though i dont explicitly reference the "header_row" variable again

[warm dove]

@misty compass

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[restive venture]

it just consumes the first line from reader. and if the first line is what the names of the columns are, and not an actual row of data, then you don't want to treat it like a regular row.

[misty compass]

!close

[warm dove]

Python help channel closed

This help channel has been closed and it's no longer possible to send messages here. If your question wasn't answered, feel free to create a new post in #1035199133436354600. To maximize your chances of getting a response, check out this guide on asking good questions.

🔒 csv reader

[restive venture]

did you figure it out, or what?

[misty compass]

no

i thought that would get rid of the help text stuff

sorry

[restive venture]

the help text stuff?

[misty compass]

yeah from @warm dove never mind though i didnt mean to close it

and no im not sure i follow what ur saying

i have my csv in front of me though

[restive venture]

so if you look at the csv, the first line of text in the file is not actual data. it's just telling you the name of each column. right?

[misty compass]

yeah

[restive venture]

so doing next(reader) gives you the next line of reader. which in this case is the first line.

[misty compass]

is header_row a variable im making up or is it inherent to the csv reader

so it's pointing the reader variable to another line ?

why am i using a variable to do that

[restive venture]

it doesn't change what object the reader variable refers to, no. it changes reader on the inside to advance to the next line.

[misty compass]

why do i need to do that with "header_row"

[restive venture]

so that when you do for row in reader:, reader continues from the second line, where the actual data starts.

[misty compass]

is there a way to do that without using a variable

[restive venture]

I don't know exactly what you mean by "using a variable", but it's not required that you assign the result of next(reader) to a variable, if you're sure you don't want to use it.

with open(filename) as f:
    reader = csv.reader(f)
    next(reader)  # no variable
    # continue as before

[misty compass]

let me try that

ok it works the same

thanks

im not sure why it was written like that but you can make a permanent action still happen even if it's in a variable assignment ?

[restive venture]

I don't know what you mean by "permanent action". If you do next(reader) it consumes the next line of reader, whether you save it to a variable or not.

next(reader) returns a string of whatever the next line is

print(next(reader).upper())

you could do this if you wanted to print the next line in all caps. idk why you would.

[misty compass]

ok

i'll close thanks

[restive venture]

bye bye

[misty compass]

!close

[warm dove]

Python help channel closed

This help channel has been closed and it's no longer possible to send messages here. If your question wasn't answered, feel free to create a new post in #1035199133436354600. To maximize your chances of getting a response, check out this guide on asking good questions.