**float
*x, *y, *z** |
Arrays of dimension *npts* that specify the
coordinates of each volume value. |

**float
*v** |
Array of volume values (dimension *npts*) that are to be plotted
at each corresponding *x*, *y*, *z* point. |

**int
npts** |
The number of points to be plotted. |

**float
vmax** |
The maximum volume value to be expected. A point plotted with this
value of volume will result in a rectangular volume that is 1/10 the size
of each axis. If you wish to start a second 4-D plot, you should call **Plot4d()**
with *vmax* = 0.0f to renormalize the internal scaling factors. |

**float
*v** |
Array of volume values (dimension *npts*) that are to be plotted
at each corresponding *x*, *y*, *z* point. |

**int
sym** |
The symbol to be plotted in the
center of each volume. If *sym* == -1,
the symbol is suppressed. |