remove row from matrix

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Jakob Hannibal
Jakob Hannibal 2014-10-31
评论： Jakob Hannibal 2014-11-4
Hello!
I have a problem where I need to remove som rows from a matrix. I need to remove all numbers under 10 and over 60 from the first row and all negative numbers from the second row. The third row has to be between 1:4. I need to print if a row has been removed, so I know which rows are missing, which I haven't implemented in the code below. I have tried in many ways and has come up with this that removes the right rows, but I am sure it can be done in a smarter way…
clc;clear; false_data = [8 20 15 35 65 35; 0.1090 -0.50 0.5170 1.0860 0.9340 0.1090;1 2 3 4 6 1]'; approved_bacteria = [1 2 3 4];
for i = 1:length(false_data(:,1)) indices = 10 > false_data(:,1) | (false_data(:,1) > 60)
false_data(indices,:) = []; end
for i = length(false_data(:,2)) indices = false_data(:,2) < 0; false_data(indices,:) = []; end
for i = length(false_data(:,3)) indices = false_data(i,3) < 1 false_data(i,3) > 4; false_data(indices,:) = []; end false_data

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Sean de Wolski
Sean de Wolski 2014-10-31
This is how I'd do it.
% Bounds
lb = [10 0 1];
ub = [60 inf 4];
% Simulate data
n = 1000;
data = [randi(100,[n,1]) randn(n,1) rand(n,1)*10];
% Apply conditions
idxrmv = any(bsxfun(@lt,data,lb) | bsxfun(@gt,data,ub),2);
% Remove
data(idxrmv,:) = [];
% print
fprintf('Removed row %3.0i\n',find(idxrmv));
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Sean de Wolski
Sean de Wolski 2014-10-31
loop over the rows of the matrix, find the columns in each row, print.
Jakob Hannibal
Jakob Hannibal 2014-11-4
When I run the function I get this errormessage:
Enter the filename to load: data0.txt
data =
25.0000 0.1090 1.0000
20.0000 0.0960 2.0000
100.0000 0 3.0000
15.0000 0.8000 5.0000
35.0000 1.0860 4.0000
40.0000 0.9340 2.0000
35.0000 0.1090 1.0000
22.0000 0.1000 1.0000
21.0000 0.1000 2.0000
16.0000 0.6000 3.0000
17.0000 0.8500 5.0000
32.0000 1.0800 4.0000
45.0000 0.9500 2.0000
37.0000 0.1100 1.0000
Error using bsxfun Non-singleton dimensions of the two input arrays must match each other.
Error in checkdata (line 10) idxrmv = any(bsxfun(@lt,data,lb) | bsxfun(@gt,data,ub),2);

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