Removing NaN from matrix

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Christian
Christian 2017-4-19
评论： Ashishkumar Gupta 2023-1-5
Hello everybody,
I have a 61x9 double matrix. The columns look like this:
Column 1: 0 1 2 3 4 5 6 7 ... NaN NaN NaN
Column 2: 0 2 3 4 5 6 7 8 4 5 6 3 NaN NaN
Column 3: 0 5 6 6 3 3 6 7 8 5 3 3 6 7 8 5 . . .
That means, every column has a certain amount of values and is filled up with NaNs to get a rectangular double matrix all in all.
Now I want to remove all the NaNs. And I am not quite sure if this is possible, because after removing the NaNs, the size of each column would differ.
For now I have tried something like this:
A(find(isnan(A)))=[]
This code removes the NaNs, but the result is a 1x445 double, where all columns are just add consecutively.
I hope you guys can help me!
Cheers
Christian
  2 个评论
Ganesh Hegade
Ganesh Hegade 2017-4-19
Its better you should replace the NaN with some values.
A(isnan(A)) = -1;
Pampa Dey
Pampa Dey 2021-8-25
how to remove nans from a column?
I have multiple .txt files in which some of them have completely nan values within my interested column how can we remove them in matlab?
could anyone please help?

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采纳的回答

Jan
Jan 2017-4-19
Exactly: This cannot work, because all columns of a matrix must have the same number of rows. You cannot remove all NaNs and keep the shape of the matrix. You have to decide, what you want instead:
X = X(~any(isnan(X, 2)))
X = X(~all(isnan(X, 2)))
X = X(~isnan(X))
Or perhaps you want a cell array containing the different columns vectors?
  2 个评论
Christian
Christian 2017-4-19
Ok, that's what I thought. So I will continue using cells instead.
Ashishkumar Gupta
Ashishkumar Gupta 2023-1-5
did not work for a .struct!!!
Any other way out to remove NaNs from a struct having 50-60 variables

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更多回答（1 个）

Biswajit Ojha
Biswajit Ojha 2019-4-30
"X = X(~any(isnan(X, 2)))
X = X(~all(isnan(X, 2)))
X = X(~isnan(X)) "
dear Jan,
can you please explain why you have used those '2' s in the command?
  1 个评论
Yuanhanqing Huang
Yuanhanqing Huang 2019-7-25
I think there are some little errors. Maybe the right code should be:
X = X(~all(isnan(X), 2))
It means that we find the rows the elements of which are all nan. '2' denotes the results are in column. That being said, the any operation is implemented regarding each row.

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