Analog Input. In this example we use a variable resistor (a potentiometer or a photoresistor), we read its value using one analog input of an Arduino or Genuino board and we change the blink rate of the built-in LED accordingly. The resistor's analog value is read as a voltage because this is how the analog inputs work.
For the Haigis formula, the a0 constant moves the power prediction curve up, or down, in much the same way that the SRK/T A-constant. The a1 constant is tied to the measured anterior chamber depth and the a2 constant is tied to the measured axial length.
Asker's rating. Report Abuse. A constant is simply a fixed or given number (or name or symbol that stands for a fixed number) -- not a variable. A coefficient is a constant, and is a multiplier of something -- typically a variable, but also functions and other things.Example (nonsensical expression): y = 2sin(3x) +4pi 2, 3, 4, and pi are constants (and some would say 2pi is a constant). 2 and 3 are coefficients.sker's rating. Report Abuse. A constant is simply a fixed or given number (or name or symbol that stands for a fixed number) -- not a variable. A coefficient is a constant, and is a multiplier of something -- typically a variable, but also functions and other things.