13x8 Matrix Cubic Interpolation

I have a matrix [13x8]. I want to cubic interpolate it to [50x8]. I tried "csapi" but I couldn't manage to figure it out.

[0.0000 0.0000 0.0000 0.0000 0.0000 0.0890 0.2860 0.4380;

0.0177 0.0648 0.0888 0.1070 0.1640 0.3680 0.5720 0.7040;

0.0594 0.1778 0.2445 0.3140 0.4250 0.6140 0.7650 0.8540;

0.2652 0.4723 0.6038 0.7260 0.8250 0.8970 0.9500 0.9820;

0.5436 0.7547 0.8852 0.9570 0.9800 0.9910 0.9980 1.0000;

0.7409 0.9056 0.9870 1.0000 1.0000 1.0000 1.0000 1.0000

0.7710 0.9260 0.9980 1.0000 1.0000 1.0000 1.0000 1.0000

0.7695 0.9260 0.9980 1.0000 1.0000 1.0000 1.0000 1.0000

0.6399 0.8297 0.9401 0.9710 0.9800 0.9850 0.9900 0.9920

0.3369 0.5788 0.7226 0.7780 0.8020 0.8270 0.8510 0.8770

0.0771 0.2463 0.3493 0.3890 0.4070 0.4300 0.4720 0.5360

0.0200 0.1019 0.1577 0.1770 0.1840 0.1940 0.2290 0.2990

0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0200 0.0510];

Answer 1

[Chris]

Like this?

V = [0.0000 0.0000 0.0000 0.0000 0.0000 0.0890 0.2860 0.4380;
0.0177 0.0648 0.0888 0.1070 0.1640 0.3680 0.5720 0.7040;
0.0594 0.1778 0.2445 0.3140 0.4250 0.6140 0.7650 0.8540;
0.2652 0.4723 0.6038 0.7260 0.8250 0.8970 0.9500 0.9820;
0.5436 0.7547 0.8852 0.9570 0.9800 0.9910 0.9980 1.0000;
0.7409 0.9056 0.9870 1.0000 1.0000 1.0000 1.0000 1.0000
0.7710 0.9260 0.9980 1.0000 1.0000 1.0000 1.0000 1.0000
0.7695 0.9260 0.9980 1.0000 1.0000 1.0000 1.0000 1.0000
0.6399 0.8297 0.9401 0.9710 0.9800 0.9850 0.9900 0.9920
0.3369 0.5788 0.7226 0.7780 0.8020 0.8270 0.8510 0.8770
0.0771 0.2463 0.3493 0.3890 0.4070 0.4300 0.4720 0.5360
0.0200 0.1019 0.1577 0.1770 0.1840 0.1940 0.2290 0.2990
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0200 0.0510];
surf(V)

F = griddedInterpolant(V,'cubic');
X = linspace(1,13,50);
Y = 1:8;
[XX,YY] = ndgrid(X,Y);
interpolated = F(XX,YY);
surf(interpolated)

[Esat Akdöngel]

Yes thank you for the answer,how can i take the values from this model i need the values actually

[Chris]

The values are in the matrix "interpolated."

Or use interp2.

Answer 2

[Image Analyst]

You can use imresize() to do bicubic interpolation, if you have the image Processing Toolbox

resizedMatrix = imresize(m, [50,8])

Answer 3

[John D'Errico]

Simplest is to just read the help for interp2. It is silly to use a lower level tool when a high level tool does exactly what you want.