Keithley 4200-SCS Reference Manual page 635

Model 4200-SCS Reference Manual
kfpexp Keithley floating point exponential
Purpose
Format
Remarks
Example
kfplog Keithley floating point logarithm
Purpose
Format
Remarks
Example
4200-901-01 Rev. S / May 2017
Supplies the base of natural logarithms (e) raised to a specified power and stores the
result as a variable.
int kfpexp(double *x, double *z);
The exponent.
x
The variable where the result of e
z
e raised to the power of the value referenced by x will be stored in the location pointed
to by z. If an overflow occurs, the result will be ±Inf. If an underflow occurs, the result
will be zero (0).
In this example, kfpexp raises the base of natural logarithms to the power specified by
the
exponent res4. The result is stored in res4e.
double res4, res4e;
.
.
measv(SMU1, &res4);/* Raise the base of natural */
/* logarithms e to the power */
/* res4; */
kfpexp(&res4, &res4e;/* return the result to res4e. */
.
.
Returns the natural logarithm of a real number to the specified variable.
int kfplog(double *x, double *z);
A variable containing a floating point number.
x
A variable where the result of ln (x) will be stored.
z
This function returns a natural logarithm, not a common logarithm. The natural
logarithm of the value referenced by x will be stored in the location pointed to by z.
If a negative value or zero (0) is supplied for x, a log of negative value or zero (0) error
will be generated and the result will be NaN (not a number).
This example calculates the natural logarithm of a real number (res1). The result is stored
in logres.
double res1, logres;
.
.
measv(SMU1, &res1);/* Measure SMU1; store in res1. */
kfplog(&res1, &logres);/* Convert res1 to a natural */
/* LOG and store in logres. */
.
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Section 8: Keithley User Library Tool (KULT)
x will be stored.
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