Keithley 2651A Reference Manual page 122

Model 2651A High Power System SourceMeter® Instrument Reference Manual
Example:
The following programming example illustrates how to output mean and standard deviation statistics
from buffer 1:
statistics = smua.buffer.getstats(smua.nvbuffer1)
print(statistics.mean, statistics.stddev)
Reading buffer attributes
Use the reading buffer attributes to access the reading buffer data. The table below displays the
attributes that you can use to access the reading buffer data.
Recall attributes
Recall attribute*
measurefunctions
measureranges
readings
sourcefunctions
sourceoutputstates
sourceranges
sourcevalues
statuses
timestamps
*
The default attribute is readings, which can be omitted. For example, both smua.nvbuffer1 and
smua.nvbuffer1.readings will access readings from buffer 1.
Examples:
The following programming example illustrates how to output 100 readings from Buffer 1:
printbuffer(1, 100, smua.nvbuffer1.readings)
Similarly, the following would output 100 source values from buffer 1:
printbuffer(1, 100, smua.nvbuffer1.sourcevalues)
The default reading attribute is readings, and can be omitted. Thus, the following would also output
100 readings from buffer 1:
printbuffer(1, 100, smua.nvbuffer1)
2651A-901-01 Rev. A / March 2011
Description
An array (a Lua table) of strings indicating the function measured for the
reading (current, voltage, ohms, or watts).
An array (a Lua table) of full-scale range values for the measure range used
when the measurement was made.
An array (a Lua table) of the readings stored in the reading buffer. This array
holds the same data that is returned when the reading buffer is accessed
directly; that is, rb[2] and rb.readings[2] access the same value.
An array (a Lua table) of strings indicating the source function at the time of the
measurement (current or voltage).
An array (a Lua table) of strings indicating the state of the source (off or on).
An array (a Lua table) of full-scale range values for the source range used
when the measurement was made.
If enabled, an array (a Lua table) of the sourced values in effect at the time of
the reading.
An array (a Lua table) of status values for all of the readings in the buffer. The
status values are floating-point numbers that encode the status value into a
floating-point value. See Buffer status
If enabled, an array (a Lua table) of timestamps, in seconds, of when each
reading occurred. These are relative to the basetimestamp for the buffer. See
Reading buffer commands (on page 3-11).
Section 3: Functions and features
(on page 3-16).
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