Create a mesh with four variables

Hello,

I've got my x, y and z components which contain four variables. I would like to know if there is a matlab function, similar to meshgrid, which creates a 4^n x 4^n matrix.

Thank you

Ben

Answer 1

[Honglei Chen]

doc ndgrid

http://www.mathworks.com/help/techdoc/ref/ndgrid.html

[Walter Roberson]

Maybe, but the output size would seem to be entirely wrong. ndgrid() would be used to create an (n x n x n x n) = n^4 array, not a 4^n x 4^n array.

[C1, C2, C3, C4] = ndgrid(component1_values, component2_values, component3_values, component4_values);
x = f1(C1, C2, C3, C4);
y = f2(C1, C2, C3, C4);
z = f3(C1, C2, C3, C4);

For example,

x = C1.^3 - 5*C2.^2 + cos(C3) - arctan(C4);

Answer 2

[kawak]

Thank you Honglein Chen for your answer,

However I don’t think that ndgrid() will create a full grid.

For example, if you tape the following commands

>> [X1,X2,X3,X4] = ndgrid(0:1:2); >> A=[X1 X2 X3 X4]

You will see that the mesh A does not have the point A=0 0 0 0.

Thanks

Ben

[Honglei Chen]

Hi Kawak,

You are not reading the result correctly. For example, X1 here is a 4-dimensional array. So to look for a given point, you need to find the corresponding element in each of these four matrices. For example

>> [X1(1,1,1,1) X2(1,1,1,1) X3(1,1,1,1) X4(1,1,1,1)]

ans =

       0     0     0     0

[kawak]

Ah ok.. :-) Thanks a lot Chen, it does work now.

Thanks again