how to replace a sequence of specific length of NaNs?

Hello,

Please help me with the following:

Consider vector

A=[2.15,NaN,NaN,1.14,NaN,NaN,0.59,NaN,NaN,0.14,NaN,NaN,0,NaN,NaN,NaN,NaN,0.08,NaN,NaN,0.39];

How can replace all the NaN sequences that are not of length=2 (i.e. not equal with the rest) with another value, e.g. with 0;

In the above example all the sequences that need to be replaced are of length = 4.

Thanks,

Pavlos

Answer 1

[Walter Roberson]

replacement_value = 0;
mask = [false; isnan(A(:)); false].';
nan_start = strfind(mask, [0 1]);
nan_end = strfind(mask, [1 0]);
not_len_2_idx = find( (nan_end - nan_start) ~= 2 );
Anew = A;
for K = not_len_2_idx
  Anew( nan_start(K) : nan_end(K)-1 ) = replacement_value;
end