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 ===== Simple linear conversion =====
A very simple method (no floating point, no algebraic formulas) for
 linear conversion of sensor output data to human-understandable units.

 === Example 1, temperature ===

 Two points are given: Sensor output 400 and 1200 correspond
 to 10 and 36.3 degrees Celsius respectively.\\
 To get rid of floating point, we calculate Celsius in tenths of degrees:

    Sensor  Celsius
     400     100
    1200     363
    (800)   (263)  (Distance)

 Let's take:
    SensorZ     = the given sensor value closest to zero (400)
    CelsiusZ    = the corresponding Celsius value (100)
    SensorDist  = distance between the two sensor values (800)
    CelsiusDist = distance between the two Celsius values (263)

 Then the conversion looks like this:

    : >CELSIUS    ( sensor -- celsius )
      SensorZ -   CelsiusDist SensorDist */   CelsiusZ + ;

 The working forth definition is:

    : >CELSIUS ( sensor -- celsius ) 400 - 263 800 */ 100 + ;



 NEGATE must be inserted after */ when increasing sensor values
 correspond to decreasing Celsius values.

 === Example 2 ===

    Sensor  Celsius
     400     363
    1200     100
    (800)   (263)  (Distance)

 The forth definition:
    : >CELSIUS ( sensor -- celsius ) 400 - 263 800 */ NEGATE 363 + ;


 ( an,jan2025)