The thermodynamic quantities for the temperature range limited by a
lower bound of *nnn* Kelvin and an upper bound of *mmm* Kelvin (both integer
numbers), the step size
being calculated in order to give approximately 20 points, and a
reasonable value for the step. The size of the step in Kelvin degrees
will be 1, 2, or 5, or a power of 10 times these numbers.