Keithley 4200A-SCS - EXPFITA Formulator Function

Section
6: Clarius Model 4200A-SCS Parameter Analyzer
Reference Manual
6-248 4200A-901-01 Rev. C / February 2017
EXPFITA Formulator function
Performs an exponential fit. Fits the following exponential relationship to a specified range of values in two
columns (vectors): one column, VX, containing X values and the other column, VY, containing Y values:
Y = EXPFITA * e
(EXPFITB * X)
Where EXPFITA and EXPFITB are fit constants.
Usage
EXPFITA(VX, VY, STARTPOS, ENDPOS)
VX
The name of any column (vector) listed under Columns
VY
The name of any column (vector) listed under Columns
STARTPOS
For the range of X and Y values to be exponentially fitted, the row number (index) of
the starting values
ENDPOS
For the range of X and Y values to be exponentially fitted, the row number (index) of
the ending values
Details
If a VX or VY value at either STARTPOS or ENDPOS is an invalid number (that is, the value is #REF),
the function will not return a valid result.
Example
DIODEI = EXPFIT(ANODEV, ANODEI, 2, LASTPOS(ANODEV))
Also see
EXPFIT (on page 6-247)
EXPFITB (on page 6-249)