Printf: print formatting ^{[21 May 2009]}

(Python environment -see also the unix man page "man printf")

strings: value

print "http://%s:234678" % "127.0.0.1"

It means that '%s' will be replace with the value '127.0.0.1':

http://127.0.0.1:234678

strings: variable

ip = '192.168.0.1'
print "http://%s:234678" % ip

It means that '%s' will be replace with the value of the variable 'ip':

http://192.168.0.1:234678

list of strings

item = "you"
print "%s and %s" % ("me", item)

It means that the first '%s' will be replace with the first element of the list (the string 'me'; the second '%s' will be replaced with the second value of the list (the value of the variable 'item'). Be sure to use brackets.

me and you

integers and floating point numbers

It's the same but you must use '%d' for integers and '%f' for floating points.