## Retrieving the Results of Previous Sweeps

The command CALCulate<Ch>:DATA:NSWeep? SDATa, <Trace_Hist_Count>
retrieves the results of any sweep within a previously defined single sweep group. This means that, in single sweep mode, you can first measure a specified number of sweeps (SENSe<Ch>:SWEep:COUNt <sweeps>
) and then read any of the data traces acquired.

This feature has no equivalent in manual control where always the last data trace is displayed.

// Reset the analyzer

*RST

:SYSTEM:DISPLAY:UPDATE ON

// Create a second channel with a second trace.

:CALCULATE2:PARAMETER:SDEFINE "Trc2","S11"

:CALCULATE2:PARAMETER:SELECT "Trc2"

:DISPLAY:WINDOW2:STATE ON

:DISPLAY:WINDOW2:TRACE1:FEED 'Trc2'

// Select active trace for the created channel 2. Adjust the number of sweep points.

:CALCULATE2:PARAMETER:SELECT "Trc2"

:SENSE1:SWEEP:POINTS 3

:SENSE2:SWEEP:POINTS 4

// Set sweep time and sweep count for the channels

// (3 traces per single sweep in channel 1, 4 traces in channel 2)

:SENSE1:SWEEP:TIME 1 S

:SENSE2:SWEEP:TIME 1 S

:SENSE1:SWEEP:COUNT 3

:SENSE2:SWEEP:COUNT 4

// State that INITIATE<Ch>:IMMEDIATE will start a single sweep for the

// referenced channel <Ch> only, not for all channels

:INITIATE:IMMEDIATE:SCOPE SINGLE

// Select single sweep mode and measure a single sweep group for channels no. 1 and 2

:INITIATE:IMMEDIATE:SCOPE SINGLE

:INITIATE1:IMMEDIATE; *WAI

:INITIATE2:IMMEDIATE; *WAI

// Read trace data (without history, i.e. the last trace acquired in each channel)

:CALCULATE1:DATA? SDATA

:CALCULATE2:DATA? SDATA

// Read last and previous trace data in channel 1 and 2

:CALCULATE1:DATA:NSWEEP? SDATA, 1 // last trace data

:CALCULATE1:DATA:NSWEEP? SDATA, 3 // previous trace data

:CALCULATE2:DATA:NSWEEP? SDATA, 1 // last trace data

:CALCULATE2:DATA:NSWEEP? SDATA, 4 // previous trace data