MathGroup Archive 2010

[Date Index] [Thread Index] [Author Index]

Search the Archive

Default and head in function argument


Hi,

I know how to define a function so that it evaluates only when the
head of the argument is of a certain type:

Clear[f];
f[x_Integer?Positive] := x^3
f[3]
f[3.1]
f[-3]

27
f[3.1]
f[-3]

and I also know how to set default to an argument of a function like
so:

Clear[f]
f[x_:3]
f[]

27

How do I do both i.e., specify head and default value?

Thanks,

NP


  • Prev by Date: Re: A new graphic user interface
  • Next by Date: parallel computing and message disabling
  • Previous by thread: Re: Rearrange equation II
  • Next by thread: Re: Default and head in function argument