With a Pre-Configured you can optionally use the Edit Trace window to Configure Multiple Data Sources for a Trace.
With an ad hoc Trend, you use TrendSpec to define the data source(s) (or origins) of each trace.
A trace’s value comprises the sum of the value(s) of its origin(s). Hence, if the trace has two origins, its value comprises the sum of those two values. If an ad hoc Trend’s trace has multiple origins, you need to include a separate SOURCE section for each origin within the TRACE’s section:
TREND
(
TRACE(<Data Mode>,<Y-axis Name>,
SOURCE (<Source1 Name>,<SOURCE1 Optional Values>),
SOURCE (<Source2 Name>,<SOURCE2 Optional Values>),...,
SOURCE (<Sourcen Name>,<SOURCEn Optional Values>),
<TRACE Optional Values>),
XAXIS(<X-axis Mode>,<XAXIS Optional Values>),
YAXIS(<Y-axis Name>,<YAXIS Optional Values>),<TREND Optional Values>
)
There are restrictions that limit whether a trace can have multiple sources (see Rules for Traces that have Multiple Sources).
For an example that demonstrates how TrendSpec can be used to define a multiple source trace, see Use TrendSpec to Produce a Trace that has Multiple Data Sources.