Python is a scripting language.
There are two versions, 2.x and 3.x
main
Use the __name__
parameter to determine if you are calling your script from the command line.
#!/usr/bin/python
__author__ = 'magicmonster'
def main():
print __name__
if __name__ == "__main__":
main()
Modules
import
Before using a module you must import it. e.g. if you want to use the sys module, add the following to the top of your python script file.
import sys
args
Command line arguments are accessible via sys.argv
. As with C, argv[0]
contains your script file.
Strings
Join
You can join a list of strings to make one string.
long_string = ",".join(["apple","banana","carrot"])
Casting
To convert an int into a string, use str
String value present in a set
Use the in
operator to test whether a value is present in a set.
>>> 'apple' in ('apple','pear','banana')
True
trim
Use strip
instead. e.g. to trim a trailing slash, use rstrip
>>> "dir/".rstrip("/")
'dir'
Built-in functions
len
len
returns the length of a String or array.
>>> len("apple")
5
>>> len(["red", "green"])
2
Classes
It is possible to define a class that holds state.