Function healpixK( pixelsize )

Description:
Gives the HEALPix resolution parameter suitable for a given pixel size. This k value (also variously known as order, level, depth) is the logarithm to base 2 of the Nside parameter.
Parameters:
pixelsize (floating point)
pixel size in degrees
Return Value (integer):
HEALPix order k
See Also:
HEALPix web site
Signature:
int healpixK(double)