can anybody help me with this error???

 x1=sortrows(xf,2);
 p=round(x1);
 classes=20;
 array=zeros(size(classes),3)
 min1=min(p(:,2));
 max1=max(p(:,2));
 classwidth=(max1-min1)/classes;
 d=ceil(classwidth);
 sum=0; j=1;k=1;n=0;
 lowerlimit=min1:d:max1;
 cw=d-1;
 upperlimit=cw+lowerlimit;
 ll=lowerlimit';
 ul=upperlimit'; 
for k=1:classes
    for i=1:size(p)
      if p(i,2)>=ll(k) && p(i,2)<=ul(k) 
          sum=sum+p(i,1);
      end
    end
    array(k,1)=sum;    
    array(k,2)=ll(k);
    array(k,3)=ul(k);
    sum=0;

 end
The error is in this line 
Index exceeds matrix dimensions.

Error in ==> if p(i,2)>=ll(k) && p(i,2)<=ul(k)

[Wayne King]

I don't think this can work:

 classes=20;
 array=zeros(size(classes),3)

size(classes) should be a scalar

also, please give the size of x1.

[Jan]

Please use meaningful tags. Of course all questions in a Matlab forum concern "matlab".

[Sony]

size of x1 and xf is 63 rows and 2 columns

Answer 1

[Jan]

You can use the debugger to check, what's going on:

dbstop if error

Then start the program again. When Matlab stops at the error inspect the values of i and k as well as the sizes of p, ll and ul.

It is not possible in theory that we can fix the problem, because all we have is the failing code, but we cannot guess its intention reliably.