Re: how to test where a list contains constant(s) or not
- To: mathgroup at smc.vnet.net
- Subject: [mg91996] Re: how to test where a list contains constant(s) or not
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Tue, 16 Sep 2008 19:24:35 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <gal3iu$e0a$1@smc.vnet.net>
Aya wrote:
> case1: { a, b, c, Pi } gives true because of Pi
> case2: { a, b, c, 0.0001} gives true because of 0.0001
> case3: { a, b, c, 2 + Pi I } gives ture becase of 2 + Pi I
> case4: { a, b, c} gives false
>
> is this function right ?
>
> ComplexQ[z_] := NumericQ[ z ] || ( NumericQ[ z ] && SameQ[ Head[ z ],
> Complex] )
> IsConstantsIn[ lstList_ ] :=
> Module[ { intLength },
> intLength = Length@Select[ lstList, ComplexQ[ # ]& ];
> If[ intLength > 0, Return[ True ], Return[ False ] ];
> Return[ False ];
> ]
>
As written above, the predicate ComplexQ is equivalent to NumericQ. So
you could write your function directly as follows:
In[1]:= IsConstantsIn[lstList_] :=
If[Length@Select[lstList, NumericQ[#] &] > 0, True, False]
(* Now, is this what you are looking for? I do no know. You should
describe precisely what you intent to do. *)
case = {{a, b, c, Pi}, {a, b, c, 0.0001}, {a, b, c, 2 + Pi I}, {a, b,
c}};
IsConstantsIn /@ case
Out[3]= {True, True, True, False}
In[4]:= NumericQ /@ case[[4]]
Out[4]= {False, False, False}
In[5]:= Head /@ case[[4]]
Out[5]= {Symbol, Symbol, Symbol}
Regards,
-- Jean-Marc