Surface Plots of Nonuniformly Sampled Data
You can use
meshgrid to create a grid of uniformly sampled data points at which to evaluate and graph the
sinc function. MATLAB then constructs the surface plot by connecting neighboring matrix elements to form a mesh of quadrilaterals.
To produce a surface plot from nonuniformly sampled data, first use
griddata to interpolate the values at uniformly spaced points, and then use
surf in the usual way.
Example -- Displaying Nonuniform Data on a Surface
This example evaluates the
sinc function at random points within a specific range and then generates uniformly sampled data for display as a surface plot. The process involves these tasks:
linspaceto generate evenly spaced values over the range of your unevenly sampled data.
meshgridto generate the plotting grid with the output of
griddatato interpolate the irregularly sampled data to the regularly spaced grid returned by
linspacefunction provides a convenient way to create uniformly spaced data with the desired number of elements. The following statements produce vectors over the range of the random data with the same resolution as that generated by the -8:.5:8 statement in the previous
griddatato interpolate the values of the function at the uniformly spaced points, based on the values of the function at the original data points (which are random in this example). This statement uses a triangle-based cubic interpolation to generate the new data.
|Visualizing Functions of Two Variables||Parametric Surfaces|
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