Extracting values from a matrix

Hi Hello, i hope eveyrone is doing good, i have a matrix (6100,1000) and i would like to extract some values , the rows of my matrix contains values but most of it's -300, e,g first row ( -300 -300 -300 ......... -124 -300 -300 -300) so i would like to extract 10 values that are not equal to -300, but in the case where i dont have other values i can take -300 only to fill it, basically i would like to do this for my whole matrix

thank you

[dpb]

You know what your intent is; we don't except by the description you post. There's too much not explained here -- for example, are you just wanting some number of values out of the total number that are in the file, selecting all of those that aren't -300 first irrespective of their position in the file? Or do you want the rows that have something other than -300 by row; a specific number of rows overall? Or...???

Give us a an example -- explain precisely what your expected output would be.

It would help to have a sample file -- attach a .mat file

[MEHDI HAMIDI]

So, what i want, is to extract the 10 first not -300 values if there is, if there is not 10 values that are not equal to -300 i will take the -300 values only to fill my vector, the output should be 6100 vectors with a size of 10

i hope it is clear now

Answer 1

[Image Analyst]

Do they need to be in any particular order? Otherwise just sort and take the first 10 elements. Like for a single row, do this:

sortedValues = sort(oneRow, 'descend');
first10 = sortedValues(1:10);

Can you supply a sample matrix?

[MEHDI HAMIDI]

Hello sir thanks for answering me, but i am not looking to short the 10 first values, i think you misunderstood me, here's my matrix, i want to extract 10 values that are not equal to -300, ( if there is 10 values ), if there is not 10 values ( that are not equal to -300 ) in this case i take the value -300 only to fill my vector, e,g if on the first row there are values ( not equal to -300) i only take 10, if there are 7 values only ( not equal to -300) in this case i fill the 3 missing spots with the value -300

i hope it's clear now thank you

[dpb]

images do NO good whatsoever -- as noted above, attach a .mat file of a portion of your file that folks can download to play with. Particularly, they do no good when all they show is a single value so they have no bearing on illustrating the data pattern to be expected.

[dpb]

Unless position order in the original matrix is important, IA's answer will select and return to you the Nx10 array that, unless there are no elements larger then -300 but there are elements ~=-300 but smaller. It may not be robust depending upon the data characteristics but it would match the description posted so far..it's not precise enough to define a unique solution.

[MEHDI HAMIDI]

Here the data

[MEHDI HAMIDI]

Thanks so much you helped a lot this is what i wanted, i used that and i made this

SortedData = [];

for i = 1 : 1 : length(Data)

SortedData(i,:)=sort(Data(i,:), 'descend');

end

SortedData = SortedData(:,1:10);

[Jan]

@MEHDI HAMIDI: Or simpler without a loop:

SortedData = sort(Data, 2, 'descend')

[MEHDI HAMIDI]

Yes that works also thanks for sharing with me your solution i really appreciate it sir