void contour
(fun, x, nx, y, ny, min, step, max, lnstyle, labint) |
CNTPLT.C |
Level
3 |

float
(*fun)(float, float) |
A user-defined function which returns z = fun(x,y). |

float
*x |
The x vector. |

int
nx |
The number of x values (must be odd). |

float
*y |
The y vector. |

int
ny |
The number of y values (must be odd). |

float
min |
The minimum contour level. |

float
step |
The interval between contour levels. |

float
max |
The maximum contour level. |

int
*lnstyle |
An array of coded numbers for changing line styles and/or colors for
each contour level. See the explanation at the beginning of this section.
This specification will not handle the extended GraphiC colors and is retained
for compatibility purposes.
If lnstyle == NULL, the more powerful specification capability
of contcolor() will be used (recommended). |

int
labint |
Labels are placed on every labint contour.
If labint = 0, contour labels are suppressed. |

contour() produces level contours for the function fun(x,
y). That is, for each value of level C, the curve fun(x,
y)
= C is plotted. For best results, the size of the x-y
grid squares should be small compared to the length in which fun(x,
y) varies significantly. contour() creates its own array
of linearly spaced levels. Because contour() must evaluate the function
on each grid point, it can take a long time to do this, especially if the
function is complicated and if you don't have a math coprocessor. |