hello, how can I resolve this?

2	1	2	     1    
2	2	4	      1  
2	3	8	      1
2	4	16	      1
2	5	32	      1
2	6	64	      1
2	7	128	      1
2	8	256	      1
2	9	512	      1
2	10	1024	NaN
2	11	2048	NaN
2	12	4096	NaN

hi, suppose that I have the matrix below and (where NaN is a string) how can I calculate the number of NaNs of the fourth column of matrix and assign it to a variable called “N_NAN”? Thank you

[darova]

Replace NaN with 1

Answer 1

[KALYAN ACHARJYA]

data=[2	1	2	  1    
2	2	4	      1  
2	3	8	      1
2	4	16	      1
2	5	32	      1
2	6	64	      1
2	7	128	      1
2	8	256	      1
2	9	512	      1
2	10	1024	NaN
2	11	2048	NaN
2	12	4096	NaN];
NaN_sum=sum(isnan(data(:,4))); %Its gives the sum of NaN
% Find the  r and c of NaN
[r c]=find(isnan(data));

Now replace those r,c with new strings N_NAN, for that you may require to convert the array to cell array, right?

[Walter Roberson]

? Why are you doing (isnan(data)==1)==1 ? isnan(data) is the same test as isnan(data)==1 which is the same test as (isnan(data)==1)==1

[darova]

I agree. THere is no need fo such overcomplications

[KALYAN ACHARJYA]

Yes, its my bad. Thanks for pointing it out @Walter Sir

Thanks @Darova