General form 9:

.MEASURE {DC|AC|TRAN|SP} result  param='expression'

Measure statement:

.param fval=5

.measure tran yadd param='fval + 7'

will evaluate the given expression fval + 7 and return the value 12.

'Expression' is evaluated according to the rules given in Chapt. 2.8.5 during start up of ngspice. It may contain parameters defined with the .param statement. It may also contain parameters resulting from preceding .meas statements.

.param vout_diff=50u

...

.measure tran tdiff TRIG AT=1m TARG v(2) VAL=-0.8 CROSS=3

.meas tran bw_chk param='(tdiff < vout_diff) ? 1 : 0'

will evaluate the given ternary function and return the value 1 in bw_chk, if tdiff measured is smaller than parameter vout_diff.

The expression may not contain vectors like v(10), e.g. anything resulting directly from a simulation. This may be handled with the following .meas command option.