Putting a line from a text file into a variable, then moving to nextline

[Vernon Wenberg III]

I'm not really sure how readline() works. Is there a way to iterate
through a file with multiple lines and then putting each line in a
variable in a loop?

[Jorge Godoy]

Vernon Wenberg III wrote:

I'm not really sure how readline() works. Is there a way to iterate
through a file with multiple lines and then putting each line in a
variable in a loop?

To know how something works you can always check the docs about this
specific functionality:

>>a = open('a')
help(a.readline)

Help on built-in function readline:

readline(...)
readline([size]) -next line from the file, as a string.

Retain newline. A non-negative size argument limits the maximum
number of bytes to return (an incomplete line may be returned then).
Return an empty string at EOF.

>>help(a.readlines)

Help on built-in function readlines:

readlines(...)
readlines([size]) -list of strings, each a line from the file.

Call readline() repeatedly and return a list of the lines so read.
The optional size argument, if given, is an approximate bound on the
total number of bytes in the lines returned.

>>>

If you are creating new variables on every loop iteration you might be
interested in two things:

- you can loop directly through the file, on a line by line basis
- you can assign the read line to a an array

[Tim Chase]

I'm not really sure how readline() works. Is there a way to iterate

through a file with multiple lines and then putting each line in a
variable in a loop?

You can use readlines() to get the whole line (including the
newline):

lines = file('x.txt').readlines()

or you can iterate over the file building a list without the newline:

lines = [line.rstrip('\n') for line in file('x.txt')]

Thus, line[0] will be the first line in your file, line[1] will
be the second, etc.

-tkc

[Michal Bozon]

On Sun, 07 Oct 2007 12:00:44 +0000, Vernon Wenberg III wrote:

I'm not really sure how readline() works. Is there a way to iterate
through a file with multiple lines and then putting each line in a
variable in a loop?

There are always more ways how to do it.. one of them is:

f = open(filename)
for line in f:
# you may then strip the newline:
line = line.strip('\n')
# do anything you want with the line
f.close()

[Tim Williams]

On 07/10/2007, Tim Chase <py*********@tim.thechases.comwrote:

I'm not really sure how readline() works. Is there a way to iterate
through a file with multiple lines and then putting each line in a
variable in a loop?

You can use readlines() to get the whole line (including the
newline):

lines = file('x.txt').readlines()

or you can iterate over the file building a list without the newline:

lines = [line.rstrip('\n') for line in file('x.txt')]

Thus, line[0] will be the first line in your file, line[1] will
be the second, etc.

or splitlines()

>> lines = open('x.txt').read().splitlines()

:)