Keithley 4200A-SCS, Reference Manual

Page: 521 / 1381

Section 6: Clarius Model 4200A-SCS Parameter Analyzer Reference Manual
6-252 4200A-901-01 Rev. C / February 2017
LINFITXINT Formulator function
Finds a linear equation and returns the X intercept.
Usage
LINFITXINT( 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 The row number (index) of the first set of X and Y values
ENDPOS The row number (index) of the second set of X and Y values
Details
Finds a linear equation and returns the X intercept as follows:
•
Finds a linear equation of the form
Y = a + bX
from two sets of
X
and
Y
values selected from
two columns (vectors),
VX
and
VY
. This equation corresponds to a line drawn through two points
on a curve that is created by plotting the values in
VY
against the values in
VX
. The two points are
specified by the arguments
STARTPOS
and
ENDPOS
.
•
Returns the X intercept of the linear equation (value of
-a/b
in
Y = a + bX
).
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.
To return the
X
intercept of a linear regression fit for two columns (vectors), use the
REGFITXINT
function.
Example
EARLYV = LINFITXINT(COLLECTORV, COLLECTORI, 56, 75)
Also see
REGFITXINT (on page 6-262)