Estimate, in a loose categorical fashion, the magnitude of the quantity "value"
in proportion to the quantity "baseline".
Both are assumed nonnegative (NOT checked.)
Return one of:
"S" ("Small" ; up to 1/2 the size)
"C" ("Comparable" ; from 1/2 to double)
"L" ("Large" ; over double the size)
This method is meant for largescale computations, and on purpose avoids doing divisions.
TODO: a Numpy array version of it.
:param value:
:param baseline:
:return: An assessment of relative significance, as one of
"S" ("Small"), "C" ("Comparable"), "L" ("Large")
