Keithley 6517B Reference Manual page 176

Section 8: Buffer (data store)

MAX: maximum reading in buffer, for example:
MAX=+1.635968e+00 at RDG# +00090
Notes:
 Display response may be slow due to calculation of statistics for large buffers
 Exponents are in terms of primary units of function on top line (for example, volts, not
millivolts)

MIN: minimum reading in buffer, for example:
MIN=+1.627611e+00 at RDG# +00012

Average: This math operation displays the mean value of the buffered readings, for example:
Average = +1.6345e+00
The equation used to calculate the mean is:
Where: x
the result is NAN (not a number).

StdDev: This operation displays the standard deviation of the stored readings, for example:
StdDev = 1.4944e-03
The equation used to calculate the standard deviation is:
Where: x is a stored reading, and n is the number of stored readings.
i
Note that if n1, the result is NAN (not a number). These statistics are invalid if the measurement
function changed during data store (for example, when scanning different functions). The Model
6517B uses IEEE-754 floating point format for math calculations.
The last display in this series allows you to send the buffered readings to a printer.
8-8
is a stored reading, and n is the number of stored readings Note that if n = 0,
i
Model 6517B Electrometer Reference Manual
6517B-901-01 Rev. C / August 2015