Re: Count Function
- To: mathgroup at smc.vnet.net
- Subject: [mg65519] Re: [mg65501] Count Function
- From: János <janos.lobb at yale.edu>
- Date: Thu, 6 Apr 2006 06:52:01 -0400 (EDT)
- References: <200604051055.GAA21742@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
On Apr 5, 2006, at 6:55 AM, Gregory Lypny wrote:
> The syntax will be the death of me.
>
> Count[X[[All,14]], -9.] will tally how many elements in column 14 of
> matrix X are equal to -9, but I can't for the life of me figure out
> how to get how many are greater than -9. Any hint would be most
> appreciated.
>
> Greg
>
Here is a newbie approach:
In[1]:=
xmat = Table[Table[
Random[Integer,
{1, 100}], {i, 1, 20}],
{j, 1, 30}]
In[6]:=
Length[Select[xmat[[All,14]],
#1 > 9 & ]]
Out[6]=
25
János
----------------------------------------------
Trying to argue with a politician is like lifting up the head of a
corpse.
(S. Lem: His Master Voice)
- References:
- Count Function
- From: Gregory Lypny <gregory.lypny@videotron.ca>
- Count Function