CODEWITHSUNDEEP
matlabloopsindexing
gran_profaci
gran_profaci

Reputation: 8463

Sending a Data Range to Another Data Range in Matlab without a for loop

So here is what I have :

an index : [3;4;5;6;7;8;9] I have a vector that corresponds to that index : 

inVector = [10;20;30;40;50;60;70;80;90]

What I want is that I get the mean of every 3 rows in the invector. Hence,

outVector = mean(inVector[index - 2 : index]);

Hence, outVector now has [20;30;40;50;60;70;80];

Upvotes: 0

Views: 58

Answers (1)

Luis Mendo
Luis Mendo

Reputation: 112669

For arbitrary index, you can do it using cumsum:

N = 3;
aux = cumsum([0; inVector(:)]);
result = (aux(index+1)-aux(index-N+1))/N;

If index always consists of consecutive indices, it's easier to use conv (since a moving average is a convolution with a rectangular window):

N = 3;
result = conv(inVector,ones(1,N)/N,'valid');

Upvotes: 1

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