Keithley 2461, Reference Manual, Page: 685 / 1109

Section 8: TSP command reference Model 2461 Interactive SourceMeter® Instrument Reference Manual
8-12 2461-901-01 A/November 2015
buffer.getstats()
This function returns statistics from a specified reading buffer.
Type TSP-Link accessible Affected by Where saved Default value
Function Yes
Usage
buffer.getstats()
buffer.getstats( bufferVar )
statsVar = buffer.getstats( bufferVar )
bufferVar
The name of the reading buffer, which may be a default buffer (
defbuffer1
or
defbuffer2
) or a user-defined buffer; if no buffer is specified, this parameter
defaults to
defbuffer1
statsVar
A table with the following entries:
n
,
min
,
max
,
mean
, and
stddev
; see
Details
for
information on the entries
Details
This function returns a table with statistical data about the data that was placed in the reading buffer.
The instrument automatically updates reading buffer statistics as data is added to the reading buffer.
When the reading buffer is configured to fill continuously and overwrite old data with new data, the
buffer statistics include the data that was overwritten. To get statistics that do not include data that
has been overwritten, define a large buffer size that will accommodate the number of readings you
will make.
The table returned from this function provides statistics at the time the function is called. Although the
instrument continues to update the statistics, the table that is returned is not updated. To get fresh
statistics, call this function again.
The
statsVar
parameter contains the values described in the following table.
Attribute When returned Description
min
n
> 0
A table that contains data about the minimum reading value that was added
to the buffer
mean
n
> 0 The average of all readings added to the buffer
stddev
n
> 1
The standard deviation of all readings that were added to the buffer
n
Always The number of data points on which the statistics are based
max
n
> 0
A table that contains data about the maximum reading value that was added
to the buffer
If
n
equals zero (0), all other values are
nil
. If
n
equals 1,
stddev
is
nil
because the standard
deviation of a sample size of 1 is undefined.