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Re: how to check for NumericQ arbitrary data structure

• To: mathgroup at smc.vnet.net
• Subject: [mg126220] Re: how to check for NumericQ arbitrary data structure
• From: Christoph Lhotka <christoph.lhotka at fundp.ac.be>
• Date: Thu, 26 Apr 2012 05:24:46 -0400 (EDT)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <201204201144.HAA21808@smc.vnet.net> <201204210431.AAA29236@smc.vnet.net> <201204240932.FAA24447@smc.vnet.net>

Hi,

  I would like to add an "old"-style way of programming to tackle the 
problem:

data1 = {2, {Pi, 0.5}, {1/2, {I, 3 Sin[2]}, {6}}};
data2 = {a, {Pi, 0.5}, {1/2, {I, 3 Sin[2]}, {6}}};

testQ[expr_] := Block[{},
   If[
    Head[expr] === List,
    Do[testQ[expr[[i]]], {i, 1, Length[expr]}],
    If[! NumericQ[expr], Throw[False]]];
   Throw[True]
   ]

TestQ[expr_] := Catch[testQ[expr]]


TestQ[data1]
True

TestQ[data2]
False


Note, that TestQ is needed to catch the False thrown by testQ if 
!NumericQ returns True.

Best,

Christoph



On 04/24/2012 11:32 AM, Ted Sariyski wrote:
> Hi,
> I have a data structure e.g. {a,{b,c},{d,{e,f},{g}}}, which I want to
> check for NumericQ. For vectors and matrices I can use
> VectorQ[x,NumericQ] or MatrixQ[x,NumericQ]. Is there a way to check an
> arbitrary data structure that all elements are NumericQ or I have to
> construct a function for each data structure?
> Thanks in advance,
> --Ted
>
>

• References:
  • Find all roots with FindRoot
    • From: Sam Takoy <sam.takoy@yahoo.com>
  • Re: Find all roots with FindRoot
    • From: "Harvey P. Dale" <hpd1@nyu.edu>
  • how to check for NumericQ arbitrary data structure
    • From: Ted Sariyski <tsariysk@craft-tech.com>