interpolating row data in a matrix

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Natalie
Natalie on 15 Oct 2013
Answered: Natalie on 18 Oct 2013
I have a large set of data that I need to linearly interpolate evenly by a factor of 22. The way that the data is organised means that the each row of data needs to be interpolated instead of each column, how do I make it so that rows of data are interpolated instead of columns?

Accepted Answer

Natalie
Natalie on 18 Oct 2013
Sat down with someone and worked it out together:
num_rows = length(a); num_columns = 22;
b = zeros(num_rows,num_columns); c = zeros(num_rows,num_columns);
for i = 1:num_rows
count = a(i,13);
int_c(i,:) = (0:1/(num_columns - 1):1)*c(i,count);
int_b(i,:) = interp1(b(i,1:count), b(i,1:count), new_thick(i,:),'spline');
end
end

More Answers (2)

Walter Roberson
Walter Roberson on 15 Oct 2013
newV = interp1(X, V.', newX) .';
  1 Comment
Natalie
Natalie on 16 Oct 2013
Sorry, forgot to mention that there are a bunch of Nan values so this doesn't work

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Youssef  Khmou
Youssef Khmou on 15 Oct 2013
large data means down sampling?
If it is the other case, you can interpolate row by row as in this example :
r=randn(30);
for n=1:30
G(n,:)=interp(r(n,:),22);
end
  1 Comment
Natalie
Natalie on 16 Oct 2013
Sorry what I meant by large data I meant large in size, about 1000 rows and 100 columns. I wish to interpolate the data along the rows not columns, so interpolate the data present in each column of a row. Also I forgot to mention that there is also the problem of a lot of Nan values

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