### LAPLACE

Performs a Laplacian convolution as an edge detector in a two-dimensional NDF

#### Description:

This routine calculates the Laplacian of the supplied two-dimensional NDF , and subtracts it from the original array to create the output NDF. The subtractions can be done a specified integer number of times. This operation can be approximated by a convolution with the kernel:

$\begin{array}{ccc}\hfill N\hfill & \hfill -N\hfill & \hfill -N\hfill \\ \hfill N\hfill & \hfill +8N\hfill & \hfill -N\hfill \\ \hfill N\hfill & \hfill -N\hfill & \hfill -N\hfill \end{array}$

where N is the integer number of times the Laplacian is subtracted. This convolution is used as a uni-directional edge detector. Areas where the input data array is flat become zero in the output data array.

#### Usage:

laplace in [number] out [title]

#### Parameters:

Input NDF.
Number of Laplacians to remove. [1]
##### OUT = NDF (Write)
Output NDF.
The title for the output NDF. A null value will cause the title of the NDF supplied for Parameter IN to be used instead. [!]