"Gary Herron" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] [EMAIL PROTECTED] wrote:
You have several ways to import a module, and your choice determines how you access things. Method 1: import math Then use: math.pi, math.sqrt, math.sin, math.cos, ... Method 2: from math import pi, sqrt Then use pi, and sqrt. But other module attributes (like sin, and cos) are not accessible. Method 3: from math import * Then use pi, sqrt, cos, sin, and anything else defined by the module. (This is sometime frowned upon, but there's no reason to do so here.) | ===================================== | There are two good reasons for the frown. One is for the potential conflict between builtin names, imported names (from possibly multiple modules), and names defined in the module. Builtins and math both have 'pow' functions that I believe are slightly different (or maybe once were). Math and cmath have 13 functions with duplicate names but different input and output (2.5). Importing * from both would be disasterous. The other is that someone not familiar with the imported module(s) will not know where a particular name came from when reading the code. Both problems are obvious worse with multiple imports. Method 4: (my favorite when using multiple names from a module) import math as m Then use m.pi, etc. tjr -- http://mail.python.org/mailman/listinfo/python-list
