count element in column
On 05-Jan-05 Frederic renaud wrote:
Hi,
I 've a matrix n*1 (thus a column) and I would like to
count the number of negative element inside.
Can you help me?
Thanks!
eg:
res[,1]= 1
-3
-1
How obtain the number 2 (number of negative-element)?
If there is only one column, then either sum(x<0) or sum(x[,1]<0) If there is more than one column, then sum(x[,1]<0) sum(x[,2]<0) ... does it for each column, one at a time, and colSums(x<0) does it for all the columns at once (but separately), while sum(x<0) does it for the whole matrix (without regard for columns). Best wishes, Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk> Fax-to-email: +44 (0)870 094 0861 [NB: New number!] Date: 05-Jan-05 Time: 17:43:03 ------------------------------ XFMail ------------------------------