A calibration polynomial is a type of array value whose keys represent the real number coefficients of a polynomial. This polynomial is generally used to convert a raw signal to physical units or to apply a correction to another value. The coefficients are listed in ascending power order, starting from the offset (x0). So the coefficient at #0 is the intercept, the one at #1 is the slope, the one at #2 is x2, etc.

Intercept 0.25 and slope 0.9
/#0,0.25
/#1,0.9

There are no limits to the number of coefficients involved in the calibration, but in most cases only a slope and intercept are utilized.

High order calibration
/#0,0.25
/#1,0.9
/#2,0.05
/#3,-0.04