Matrix calculation indexing conditional
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I have a matrxi of 500 rows and 6 columns. I need to sum all the rows of 2nd column of the matrix if their 3rd column and 4th coumns equal to specific numbers.
How can I do that?
Lets explain more: One column is the time. An other column is radius. We can have multiple rows of the same time. Or multiple rows that have the same radius. An other coulmn is number of cells. I want to say for all times=2 and all radius=3 sum the number of cells.
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Andrei Bobrov
2019-8-13
编辑：Andrei Bobrov
2019-8-13
Let A - your array (500 x 6):
T = array2table(A);
T_out = varfun(@sum,T,'InputVariables',2,'GroupingVariables',3:4);
9 个评论
Zeynab Mousavikhamene
2019-8-13
Andrei Bobrov
2019-8-13
编辑：Andrei Bobrov
2019-8-13
Please attach small part of your data and result for this part.
Zeynab Mousavikhamene
2019-8-13
Zeynab Mousavikhamene
2019-8-13
Andrei Bobrov
2019-8-14
T_out = varfun(@sum,T,'GroupingVariables',...
{'time','radius'},'InputVariables','cell_count');
Zeynab Mousavikhamene
2019-8-14
Thanks for the help. T_out is like this:
what is the GroupCount column?
Andrei Bobrov
2019-8-14
编辑：Andrei Bobrov
2019-8-14
GroupCount this is number of rows - ['time', 'radius'].
Zeynab Mousavikhamene
2019-8-14
Andrei Bobrov
2019-8-15
GroupCount this is numbers of the same rows in the sub-matrix of two columns - [time, radius]
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