GeezerVison is showing octave.sourceforge.io — Function Reference: del2
- : d = del2 (M)
- : d = del2 (M, h)
- : d = del2 (M, dx, dy, …)
-
Calculate the discrete Laplace
operator.
For a 2-dimensional matrix M this is defined as
1 / d^2 d^2 \
D = --- * |--- M(x,y) + --- M(x,y) |
4 \ dx^2 dy^2 /
For N-dimensional arrays the sum in parentheses is expanded to include
second derivatives over the additional higher dimensions.
The spacing between evaluation points may be defined by h, which is a
scalar defining the equidistant spacing in all dimensions. Alternatively,
the spacing in each dimension may be defined separately by dx,
dy, etc. A scalar spacing argument defines equidistant spacing,
whereas a vector argument can be used to specify variable spacing. The
length of the spacing vectors must match the respective dimension of
M. The default spacing value is 1.
At least 3 data points are needed for each dimension. Boundary points are
calculated from the linear extrapolation of interior points.
See also: gradient, diff.
Package: octave