reading n columns and n rows from a file

0,-69.1127,-68.9,-65.2096,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-66.5,-2,-2,-2,0,0,0

0.027,-69.1062,-68.8937,-65.2083,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-66.4966,-2,-2,-2,0,0,0

0.054,-69.0996,-68.8874,-65.2069,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-66.4933,-2,-2,-2,0,0,0

0.081,-69.0931,-68.8811,-65.2056,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-66.4899,-2,-2,-2,0,0,0

0.108,-69.0865,-68.8747,-65.2043,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-66.4866,-2,-2,-2,0,0,0

0.135,-69.08,-68.8684,-65.2029,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-66.4833,-2,-2,-2,0,0,0

0.162,-69.0735,-68.8621,-65.2016,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-66.48,-2,-2,-2,0,0,0

0.189,-69.067,-68.8559,-65.2003,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-66.4766,-2,-2,-2,0,0,0

0.216,-69.0605,-68.8496,-65.1989,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-66.4733,-2,-2,-2,0,0,0

0.243,-69.054,-68.8433,-65.1976,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-66.47,-2,-2,-2,0,0,0

i want to read n lines and n columns from a file starting from line that reads 0.135 My output should look like this

-69.08,-68.8684,-65.2029,-66.4833

-69.0735,-68.8621,-65.2016,-66.48

-69.0605,-68.8496,-65.1989,-66.4733

-69.054,-68.8433,-65.1976,-66.47

[Paolo]

Can you please remove the first block of code and add the text file instead?

Answer 1

[Paolo]

Save your .txt file as file.dat. Then use:

 mydata = csvread('file.dat');
 [row,col]=find(ismembertol(mydata,0.1350));
 n = 4;
 mymatrix = mydata(row+1:row+n,col+1:col+n);