Difference between revisions of "Python:Files"

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;open (filename,"r")
 
;open (filename,"r")
:open filname for read and return the filehandle. Use w for write.
+
:open filename for read and return the filehandle. Use w for write.
  
 
Code example:
 
Code example:
Line 30: Line 30:
  
 
;f1.read(size)
 
;f1.read(size)
:Return 'size' bytest from the file as string if size is omited the entire file is returned.
+
:Return 'size' bytes from the file as string. If size is omitted or 0 the entire file is returned.
  
;f1.readlines(size)
+
;f1.readlines()
 
;list(f1)
 
;list(f1)
:Return ('size') lines from file as list.
+
:Return all lines from file as list.
  
Read through all files specified on the commandline.
+
;fileinput.input()
If there are no files on the commandline read standard input
+
:Read through all files specified on the commandline.
 +
:If there are no files on the commandline read standard input
 
<syntaxhighlight lang=python>
 
<syntaxhighlight lang=python>
 
import fileinput
 
import fileinput

Revision as of 14:20, 16 March 2018


glob.glob(filespec)
Return a list of files matching 'filespec'.

Code example:

import glob
files = glob.glob(filespec)
open (filename,"r")
open filename for read and return the filehandle. Use w for write.

Code example:

import os
if os.path.isfile(filename):
    f1 =  open (filename,"r")
with open (filename,"r") as file
Open filename for read and close at the end of the loop

Code example:

with open (filename,"r") as file:
    for line in file:
        <codeblock>
f1.read(size)
Return 'size' bytes from the file as string. If size is omitted or 0 the entire file is returned.
f1.readlines()
list(f1)
Return all lines from file as list.
fileinput.input()
Read through all files specified on the commandline.
If there are no files on the commandline read standard input
import fileinput

for line in fileinput.input():
    <codeblock>

Read from standard input and keyboard

Read from standard input

import sys

for line in sys.stdin:
    <codeblock>

Prompt and read from keyboard into a

a = input("Prompt: ")

In python2

a = raw_input("Prompt: ")