Re: how to test where a list contains constant(s) or not

*To*: mathgroup at smc.vnet.net*Subject*: [mg91984] Re: how to test where a list contains constant(s) or not*From*: Szabolcs Horvát <szhorvat at gmail.com>*Date*: Tue, 16 Sep 2008 19:22:20 -0400 (EDT)*Organization*: University of Bergen*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 ? > Most of what you've written is completely redundant. > ComplexQ[z_] := NumericQ[ z ] || ( NumericQ[ z ] && SameQ[ Head[ z ], > Complex] ) This ComplexQ function is completely equivalent to NumericQ. p || (p && q) is just p, right? > IsConstantsIn[ lstList_ ] := > Module[ { intLength }, > intLength = Length@Select[ lstList, ComplexQ[ # ]& ]; One could just use ComplexQ instead of ComplexQ[#]&. > If[ intLength > 0, Return[ True ], Return[ False ] ]; > Return[ False ]; > ] > You almost never need to use Return in Mathematica. The above two lines are equivalent to the simple expression intLength > 0 in this context. With all these simplifications your function becomes f[lst_List] := Length@Select[lst, NumericQ] > 0 But the following approach is simpler and more efficient: g[lst_List] := MemberQ[lst, _?NumericQ]