The functions for allocating memory to a 2D histogram follow the style
free. In addition they also perform their
own error checking. If there is insufficient memory available to
allocate a histogram then the functions call the error handler (with
an error number of
GSL_ENOMEM) in addition to returning a null
pointer. Thus if you use the library error handler to abort your program
then it isn’t necessary to check every 2D histogram
This function allocates memory for a two-dimensional histogram with
nx bins in the x direction and ny bins in the y direction.
The function returns a pointer to a newly created
struct. If insufficient memory is available a null pointer is returned
and the error handler is invoked with an error code of
GSL_ENOMEM. The bins and ranges must be initialized with one of
the functions below before the histogram is ready for use.
This function sets the ranges of the existing histogram h using the arrays xrange and yrange of size xsize and ysize respectively. The values of the histogram bins are reset to zero.
This function sets the ranges of the existing histogram h to cover the ranges xmin to xmax and ymin to ymax uniformly. The values of the histogram bins are reset to zero.
This function frees the 2D histogram h and all of the memory associated with it.