DM41X PPC ROM Curve Fit

The PPC ROM's CV function does similar Curve Fitting to the Advantage Pac CFIT program, without the limitation on negative data point values.

Negative X values are acceptable for Linear and Exponential curves

Negative Y values are acceptable for Linear and Logarithmic

If any data point has BOTH X and Y negative then only Linear is possible.

XEQ ALPHACVALPHA

Unlike CFIT there is no displayed menu for the top-row buttons, so you need to remember the functions.

Unlike normal Stats entry (where Y-value is entered first, then ENTER, then X-value is entered second, so that the X-value is in the X register before pressing ∑+) here we enter in “conventional” order:

• X ENTER Y Σ+
• X ENTER Y Σ+
• X ENTER Y Σ+
• X ENTER Y Σ+
• etc…..

once the data is accumulated either

• enter a fit-type digit (J)
  • 1 : Linear : Y = b*X + a
  • 2 : Exponential : Y = a*e^bX
  • 3 : Logarithmic : Y = b*Ln(X) + a
  • 4 : Power : Y = a*X^b
• then press B to Solve Type J

or

• press E to Solve Best Type

Page created : 16/02/26 20:13 GMT

Page upated : 16/02/26 21:12 GMT