Re: ordering a large matrix and referring to the named rows later
- To: mathgroup at smc.vnet.net
- Subject: [mg75353] Re: ordering a large matrix and referring to the named rows later
- From: dh <dh at metrohm.ch>
- Date: Thu, 26 Apr 2007 03:32:13 -0400 (EDT)
- References: <f0n8n0$s99$1@smc.vnet.net>
Hi,
please try to word you question more accurately. Do you mean that the
first row and first 8 column contain headers? If so, you can strip them by:
Drop[mat,{1},Range[8]]
Now, we have the matrix with values. How do you want to sort them?
Assuming we sort them according to size, we can do this by first flatten
the value into a list. Ordering[Flatten[mat]] gives you the indices of
the sorted values in the list. To get the row/col of the matrix from the
list index, say i1, assuming the matrix has cols columns:
{1+Quotient[i1-1,cols],1+Mod[i1-1,cols]}
hope this helps, Daniel
newbie wrote:
> Hi,
> I have a large matrix {5165, 26}, the first row and first 8 columns
> identify the values in the matrix. I need to be able to sort the data
> without losing the ability to reference the labels. Any ideas?
> Thank you very much for any help!
>
>