Function Reference
— Function File: [c, lev] = contourc (x, y, z, vn)

Compute isolines (countour lines) of the matrix z. Parameters x, y and vn are optional.

The return value lev is a vector of the contour levels. The return value c is a 2 by n matrix containing the contour lines in the following format

          c = [lev1, x1, x2, ..., levn, x1, x2, ...
               len1, y1, y2, ..., lenn, y1, y2, ...]

in which contour line n has a level (height) of levn and length of lenn.

If x and y are omitted they are taken as the row/column index of z. vn is either a scalar denoting the number of lines to compute or a vector containing the values of the lines. If only one value is wanted, set vn = [val, val]; If vn is omitted it defaults to 10.

For example,

          x = 0:2;
          y = x;
          z = x' * y;
          contourc (x, y, z, 2:3)
                  2.0000   2.0000   1.0000   3.0000   1.5000   2.0000
               2.0000   1.0000   2.0000   2.0000   2.0000   1.5000

See also: contour

Demonstration 1

The following code

 x = 0:2;
 y = x;
 z = x' * y;
 contourc (x, y, z, 2:3)

gives an example of how 'contourc' is used.