how can i use matlab with slope along the curve

Question

sabah 2015-2-8

回答： Star Strider 2015-2-8

i have w= 0.00229*r0^(-5/3)*f^(-11/3) how can i fond the slope from this forml where r0 is matrix (99*71)also f is (99*17)

Answer 1

Star Strider 2015-2-8

I assume both ‘f’ and ‘r0’ are the same size (either (99x17) or (99x71)), otherwise the calculation will not work.

For the slope, I would use the gradient function, with two outputs (since ‘w’ is a matrix):

w= 0.00229*r0.^(-5/3).*f.^(-11/3);  
[Wx, Wy] = gradient(w);

Here, ‘Wx’ and ‘Wy’ are the slopes in the x and y directions respectively. See the documentation for gradient for details.

Note that you need to vectorise your ‘w’ assignment calculation for it to work.