Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.


Curious
Posts:
2,359
Registered:
12/6/04


Re: Successive Matrix Midpoint Operations
Posted:
Mar 20, 2013 1:58 PM


"K" wrote in message <kicrhl$2r2$1@newscl01ah.mathworks.com>... > I'm having a tough time understanding how to do this properly. > > Imagine I have a matrix = NaN(9,1) with values at matrix(1,1) = 1 and matrix(end, 1) = 9. > So: [1;NaN;NaN;NaN;NaN;NaN;NaN;NaN;9]. I want to perform a mean of the numbers and place it in the center of the matrix so: [1;NaN;NaN;NaN;5.5;NaN;NaN;NaN;9], then I want to take a mean from the first to the center value and the mean from the center to the last value, so: [1;NaN;3.25;NaN;5.5;NaN;7.25;NaN;9] and so on until I have this: [1;2.125;3.25;4.375;5.5;6.35;7.25;8.125;9]
A couple of questions/clarifications  First, why wouldn't the first result be:
[1;NaN;NaN;NaN;5;NaN;NaN;NaN;9]
Second, is your vector (matrix) ALWAYS of odd length? Even so, what if its something like:
[1;NaN;NaN;NaN;NaN;NaN;7]
what do you want on the second iteration of:
[1;NaN;NaN;4;NaN;NaN;7]
Do you want:
[1;2.5;2.5;4;5.5;5.5;7]
or
[1;2;3;4;5;6;7]
> > I'm using mean as just an example in this case; I wish to perform other operations as I go, so the result won't be as uniform as described above, but the pattern is the same. > > Thanks for any insight, > KP



