Filter
Top Products
4-26
Programming Commands
CALCulate1 Subsystem
DATA?
Queries uncorrected frequency-spectrum data of the input laser line.
Syntax
:CALCulate1:DATA?
Attribute
Summary
Preset State: not affected
SCPI Compliance: standard
Query Only
Description The returned values are proportional to squared Watts (linear) units.
No amplitude or frequency correction is applied to the values. To
obtain the logarithmic (dB) result, normalize the returned values by
the largest value, then take five times the logarithm of the normalized
values.
Be prepared to process a large amount of data when this query is
sent. The amount of data returned depends on the measurement
update state of the instrument which can be set using the
:CALCulate1:TRANsform:FREQuency:POINts command or the resolution
argument of an instrument function. Refer to “Measurement Instruc-
tions” on page 4-15.
When NORMAL measurement update is specified, over 250 kilobytes of
data (15,047 values) can be returned to the computer. When FA S T
measurement update is specified, over 125 kilobytes of data (7,525 val-
ues) can be returned.
The following string is a typical example of the first few returned val-
ues:
+4.02646500E+001,+6.78125100E+001,+6.17986600E+001,+4.26768200E+001,+4.80245300E+00
1,+3.10491300E+001,+1.13409400E+001,+5.07832500E+001,+2.77746200E+001,+3.89150500E+0
01,+3.50217600E+001,+7.34649800E-001,+5.64983800E+000,
Notice that only measurement values are returned to the computer.
There is no first value that indicates the number of values contained
in the string as there is, for example, with the FETCh, READ, and
MEASure commands. Use the :CALCulate1:TRANsform:FRE-
Quency:POINTs command to query the number of points the
:CALC1:DATA? returns.