Re: Conditional evaluations of functions

*To*: mathgroup at smc.vnet.net*Subject*: [mg96506] Re: Conditional evaluations of functions*From*: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>*Date*: Sun, 15 Feb 2009 03:20:06 -0500 (EST)*References*: <gn5udh$gsv$1@smc.vnet.net>

Hi, your function does not work because you use the wrong syntax, you mean g[x_?(VectorQ[#, NumericQ] &)] := Total[x] Regards Jens Asim wrote: > Hi > > I am not sure why the function g does not work, but the function f > works as expected on Mathematica 7.0 on Windows XP. I want to get the > sum of a vector only if the argument supplied is a numeric vector. > > In[1]:= g[x_?VectorQ[ x, NumericQ]] := Total[x] > > In[2]:= g[{a, b , c}] > > Out[2]= g[{a, b, c}] > > In[3]:= g[{1, 2, 3}] > > Out[3]= g[{1, 2, 3}] > > In[4]:= f[x_ /; VectorQ[x, NumericQ]] := Total[x] > > In[5]:= f[{a, b, c}] > > Out[5]= f[{a, b, c}] > > In[6]:= f[{1, 2, 3}] > > Out[6]= 6 > > I also found different behavior for the function g, in Mathematica > 6.0, which also was not what I wanted. > > Thanks > > Asim >