Re: ListDimension function
- To: mathgroup at smc.vnet.net
- Subject: [mg72571] Re: [mg72595] ListDimension function
- From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
- Date: Thu, 11 Jan 2007 02:00:12 -0500 (EST)
- References: <200701100907.EAA13288@smc.vnet.net>
On 10 Jan 2007, at 09:07, carlos at colorado.edu wrote:
> Hi - I need a short function ListDimension that
> given a list returns its "brace dimensionality" =
> max number of brace levels to reach deepest entry.
> Examples
>
> List ListDimension
> a+b 0
> {1,2,x*y} 1
> {1,2,{3,0,1}} 2
> {{},{},{}} 2
> {{},{{1,2}},a} 3
>
> Built-in functions dont seem to be of help.
> Dimensions is restricted to matrix or tensor type of lists.
> Depth (minus 1) doesnt help as it is entry type dependent:
>
> Depth[{1,2,3}] -> 2
> Depth[{1,2,3+a}] -> 3
> Depth[{1,2,3+a+Sqrt[x+y]}] -> 5
>
> For the above three, ListDimension=1.
>
I think the following should work:
ListDimension[expr_]:=Depth[0*expr]-1
for example:
ListDimension[a + b]
0
ListDimension[{1, 2, x*y}]
1
ListDimension[{{}, {{1, 2}}, a}]
3
Andrzej Kozlowski
Oxford, UK.
- References:
- ListDimension function
- From: carlos@colorado.edu
- ListDimension function