Re: Count Function
- To: mathgroup at smc.vnet.net
- Subject: [mg65520] Re: [mg65501] Count Function
- From: Gregory Lypny <gregory.lypny at videotron.ca>
- Date: Thu, 6 Apr 2006 06:52:02 -0400 (EDT)
- References: <200604051055.GAA21742@smc.vnet.net> <55DC5ED6-AB89-4A5A-B93F-694BAD259CF6@yale.edu>
- Sender: owner-wri-mathgroup at wolfram.com
Thanks János,
That would be my natural inclination: to combine two functions,
Length and Select in this case, to get a result that serves as a
check of whatever I'm able to hammer out directly using something
like Count.
Regards,
Gregory
On Wed, Apr 5, 2006, at 12:47 PM, János wrote:
>
> 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