How to calculate volume of surf plot (3d plot) en matlab?

How to calculate volume of surf plot (3d plot) en matlab?

using variable x and y and function z

Answer 1

[Star Strider]

The surf plot arguments are matrices, so use trapz:

x = 1:10;
y = 1:20;
[X,Y] = meshgrid(x,y);
z = exp(-((X-5)/5.*(Y-10)/10).^2)

z = 20×10

0.5955 0.7471 0.8784 0.9681 1.0000 0.9681 0.8784 0.7471 0.5955 0.4449 0.6639 0.7942 0.9027 0.9747 1.0000 0.9747 0.9027 0.7942 0.6639 0.5273 0.7308 0.8383 0.9246 0.9806 1.0000 0.9806 0.9246 0.8383 0.7308 0.6126 0.7942 0.8784 0.9440 0.9857 1.0000 0.9857 0.9440 0.8784 0.7942 0.6977 0.8521 0.9139 0.9608 0.9900 1.0000 0.9900 0.9608 0.9139 0.8521 0.7788 0.9027 0.9440 0.9747 0.9936 1.0000 0.9936 0.9747 0.9440 0.9027 0.8521 0.9440 0.9681 0.9857 0.9964 1.0000 0.9964 0.9857 0.9681 0.9440 0.9139 0.9747 0.9857 0.9936 0.9984 1.0000 0.9984 0.9936 0.9857 0.9747 0.9608 0.9936 0.9964 0.9984 0.9996 1.0000 0.9996 0.9984 0.9964 0.9936 0.9900 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000

zvol = trapz(x,trapz(y,z))

zvol = 158.0451

figure
surf(x, y, z)
grid on

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[abdelmadjid benrabah]

thank you so much for your answer,

I would also ask when z is a function calculated by matrix 4X4, I have to use the comand trapz??

[Star Strider]

There are no specific requirements with respect to calculating it. The trapz function does trapezoidal integration, so is more accurate than sum in such instances. Use the method that provides the desired result.

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[abdelmadjid benrabah]

okay, thnx again

[Star Strider]

My pleasure!

If my Answer helped you solve your problem, please Accept it!

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