Replacing NaN with value in previous column
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Hi there, I am new in matlab and try to solve this problem for couple of hours, I need to replace all NaNs with the value in previous column and add 100:
so now I have> [14] [NaN] [9] [NaN] [13] [NaN] [13] [NaN] [9] [NaN] [15] [NaN] [11] [NaN] [10]
and I need to have> [14] [114] [9] [109] [13] [113] [13] [113] [9] [109] [15] [115] [11] [111] [10]
Thank you in advance.
采纳的回答
the cyclist
2016-5-17
Here is one way:
V = [9 nan 14 nan];
idx = find(isnan(V));
V(idx) = V(idx-1) + 100;
2 个评论
the cyclist
2016-5-17
Note that this will break if the first value is NaN, but that seems logical since you would need a different rule for that case.
Rene Sebena
2016-5-17
更多回答（1 个）
goerk
2016-5-17
Very simple solution/idea:
I suppose you have a vector
v = [14 NaN 9 NaN 13 NaN];
you can get a Mask with the positions of the NaN's
mask = isnan(v);
shift this mask one position to the left
maskValue = [mask(2:end) false];
now you can create the new vector
v2 = v;
v2(mask) = v(maskValue)+100;
Attention: Special cases (e.g. two NaN's in a row, or a NaN at the beginning) has to be handled.
3 个评论
goerk
2016-5-17
The Idea behind the proposed solutions are the same. But the two answers before need less code.
Rene Sebena
2016-5-17
goerk
2016-5-19
Do you mean something like
A.v = [14 NaN 9 NaN 13 NaN];
?
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