Keithley DMM7510 Reference Manual page 630

Model DMM7510 7½ Digit Graphical Sampling Multimeter Reference Manual
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 older 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
min
mean
stddev
n
max
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.
Use the following command to get statsVar; a table with the following entries in it: n, min, max,
mean, and stddev.
statsVar = buffer.getstats(bufferVar)
Use the following commands to print these entries:
print(statsVar.n)
print(statsVar.mean)
print(statsVar.stddev)
print(statsVar.min.reading)
print(statsVar.min.timestamp)
print(statsVar.min.seconds)
print(statsVar.min.fractionalseconds)
print(statsVar.max.reading)
print(statsVar.max.seconds)
print(statsVar.max.fractionalseconds)
print(statsVar.max.timestamp)
The commands that return minimum and maximum values each also return tables. These tables
contain the following values:
Attribute
reading
timestamp
DMM7510-901-01 Rev. B / May 2015
When returned Description
A table that contains data about the minimum reading value that was added
n > 0
to the buffer
n > 0 The average of all readings added to the buffer
The standard deviation of all readings that were added to the buffer
n > 1
Always The number of data points on which the statistics are based
n > 0 A table that contains data about the maximum reading value that was added
to the buffer
Description
The reading value
The min.timestamp is the timestamp of the minimum data point in the
buffer and the max.timestamp is the timestamp of the maximum data
point in the buffer
Section 8: TSP command reference
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