Labels: Python, Keyboard Input, Files
Ref: Python Files I/O https://www.tutorialspoint.com/python/python_files_io.htm
raw_input([prompt]): reads one line from standard input and returns it as a string. For example:
Enter your input: Hello Python Received input is : Hello Python
input([prompt]): assumes the input is a valid Python expression and returns the evaluated result to you. For example:
Enter your input: [x*5 for x in range(2,10,2)] Recieved input is : [10, 20, 30, 40]
- file object
|file.closed||Returns true if file is closed, false otherwise.|
|file.mode||Returns access mode with which file was opened.|
|file.name||Returns name of the file.|
|file.softspace||Returns false if space explicitly required with print, true otherwise.|
Creates a file object, which would be utilized to call other support methods associated with it.
file object = open(file_name [, access_mode][, buffering])
file_name: The file_name argument is a string value that contains the name of the file that you want to access.
access_mode: The access_mode determines the mode in which the file has to be opened, i.e., read, write, append, etc. A complete list of possible values is given below in the table. This is optional parameter and the default file access mode is read (r).
buffering: If the buffering value is set to 0, no buffering takes place. If the buffering value is 1, line buffering is performed while accessing a file. If you specify the buffering value as an integer greater than 1, then buffering action is performed with the indicated buffer size. If negative, the buffer size is the system default(default behavior).
A file object flushes any unwritten information and closes the file object.
The write() method writes any string to an open file.
The write() method does not add a newline character ('\n') to the end of the string
# Open a file fo = open("foo.txt", "wb") fo.write( "Python is a great language.\nYeah its great!!\n"); # Close opend file fo.close()
The read() method reads a string from an open file.
count is the number of bytes to be read from the opened file. This method starts reading from the beginning of the file and if count is missing, then it tries to read as much as possible, maybe until the end of file.
- File position
- tell(): returns the current position within the file.
- seek(offset[, from]): changes the current file position. The offset argument indicates the number of bytes to be moved. The from argument specifies the reference position from where the bytes are to be moved.
# Open a file fo = open("foo.txt", "r+") str = fo.read(10); print "Read String is : ", str # Check current position position = fo.tell(); print "Current file position : ", position # Reposition pointer at the beginning once again position = fo.seek(0, 0); str = fo.read(10); print "Again read String is : ", str # Close opend file fo.close()
Needed to import Python
rename() takes two arguments, the current filename and the new filename.
import os # Rename a file from test1.txt to test2.txt os.rename( "test1.txt", "test2.txt" )
Needed to import Python
remove() deletes files by supplying the name of the file to be deleted as the argument.
import os # Delete file test2.txt os.remove("text2.txt")
|mkdir()||os.mkdir("newdir")||create directories in the current directory.|
|chdir()||os.chdir("newdir")||change the current directory.|
|getcwd()||os.getcwd()||displays the current working directory.|
|rmdir()||os.rmdir('dirname')||deletes the directory.|