How to delete columns from a matrix, conditionally?

My data matrix consists of 400 colomns (about 25000 rows). Data set consists of number and NaN. I want to delete the columns having less than 100 data points.

My attempt is as below:

clear all
clc
%a=importdata('test_file.txt');
data=load('DATA_0.01.csv');

%My attempt

for k = 1:size(data,2);
 if sum(~isnan(data(:,k)))<100;
  data = [data(:,1:k-1),data(:,k+1:end)];
 end
end

Answer 1

[Jan]

keep = sum(~isnan(data), 1) >= 100;
data = data(:, keep);

Your approach does not work, because the matrix data is changed, but the counter k is not adjusted accordingly. With a loop:

remove = true(1, size(data, 2));
for k = 1:size(data,2);
    remove(k) = sum(~isnan(data(:,k))) < 100;
end
data(:, remove) = [];

[Andi]

Thank you!