Algorithms For Dummies

Creating functions with a variable  

number of arguments

In most cases, you know precisely how many arguments to provide with your 

function. It pays to work toward this goal whenever you can because functions 

with  a  fixed  number  of  arguments  are  easier  to  troubleshoot  later.  However, 

sometimes you simply can’t determine how many arguments the function will 

receive  at  the  outset.  For  example,  when  you  create  a  Python  application  that 

works at the command line, the user might provide no arguments, the maximum 

number of arguments (assuming there is one), or any number of arguments in 

between.

Fortunately, Python provides a technique for sending a variable number of argu-

ments to a function. You simply create an argument that has an asterisk in front 

of it, such as 

*VarArgs

. The usual technique is to provide a second argument that 

contains the number of arguments passed as an input. To see how this works, 

open a copy of IPython and type the following code:

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CHAPTER 4