Re: Mixing optional parameters and options
- To: mathgroup at smc.vnet.net
- Subject: [mg116180] Re: Mixing optional parameters and options
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Fri, 4 Feb 2011 01:39:41 -0500 (EST)
Since your definition didn't start with Clear, I suspect that old
definitions for f were still in effect.
Clear[f]
Options[f] = {bla -> True};
f[x_, y_: 11, OptionsPattern[]] := If[OptionValue[bla], x*y, y/x]
f[5]
55
f[7]
77
f[5, 7, bla -> False]
7/5
Bobby
On Thu, 03 Feb 2011 04:34:59 -0600, Peter Breitfeld <phbrf at t-online.de>
wrote:
>
> To give a simpe example which, I hope, makes clear my issue:
> Suppose I define this (silly) example function:
>
>
> Options[f]={bla->True};
> f[x_,y_:11,OptionsPattern[]:=If[OptionValue[bla],x*y,y/x]
>
> Now:
> f[5] ----> 55 (ok)
> f[5,7] ----> 35 (ok)
>
> f[5,7,bla->False] ----> 7/5 (ok)
> f[5,bla->False] ----> 5*(bla->False)
>
> I expected the result 11/5
>
> The only way I found was to define f like this:
>
> f[{x_,y_:11},OptionsPattern[]]
>
> Can it be done without the curly braces?
>
> Thank you
--
DrMajorBob at yahoo.com