Re: 3D plot from a matrix

[Juan Pablo Carbajal]

On Thu, May 15, 2014 at 12:09 PM, guido.bonalumi
<address@hidden> wrote:
> Hi everyone,
> I want to generate a 3D plot from a matrix but I do not know how to do it.
> The matrix (30x13) contains the Z values that I want to plot, but this
> values are not equally spaced:
> - in the X direction I have 30 step of data which I can consider equally
> spaced, but I want a scale from 0 to 1 on this axis (it represent a non
> dimensional coordinate);
> - in the Y direction the coordinates are from 0 to 67.9 but these values are
> not equally spaced (0, 6.8, 13.6, 20.4, 27.2, 34, 40.7, 47.5, 52.1, 56.6,
> 61.1, 65.6, 67.9); still I want the same scale as the X axis (from 0 to 1).
> Then I want to use a specific colormap, the blue to red rainbow.
>
> Can anybody help me with this?
>
> Thanks in advance to everyone.
>
>
>
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Is the data in the "meshgrid" format or is it isolated samples form
the z(x,y) surface?
If it is in meshgrid format, even though is not equally spaced, you
can  just use "mesh" or "surf" or any other plotting function.
If the data is just random samples from the z(x,y) surface, then you
have to create a mesh an interpolate your values.
Check griddata, delaunay, etc...