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Measurements

One should be aware that measurements are performed using data saved
in the plot structure as a simulation progresses. The accuracy of the
results is directly affected by the density of saved points. In
transient analysis, one may wish to use internal time point data by
setting the `steptype=nousertp` option. This avoids the
interpolation to tranient time increments which may reduce accuracy if
the increment is too coarse.

The following measurements are available when an interval has been
specified.

`find` *expr*

Evaluate the difference: *expr* at target minus *expr* at
trigger.
`min` *expr*

Find the minimum value of *expr*.
`max` *expr*

Find the maximum value of *expr*.
`pp` *expr*

Find the (maximum - minimum) value of *expr*.
`avg` *expr*

Compute the average of *expr*.
`rms` *expr*

Compute the rms value of *expr*.
`pw` *expr*

This will measure the full-width half-maximum of a pulse contained in
the interval. The baseline is taken as the initial or final value
with the smallest difference from the peak value. The algorithm will
measure the larger of a negative going or positive going pulse.
`rt` *expr*

This will measure the 10-90 percent rise or fall time of the edge
contained in the interval. The reference start and final values are
the values at the ends of the interval.

When a point has been specified, the only measurement form
available is

`find` *expr*

Evaluate *expr* at point.

A `.measure` statement can contain any number of measurements,
including no measurements. If no measurement is specified, the vector
produced contains only zeros, however the scale vector contains the
start and stop values, which may be the only result needed. The
created vector, which is added to the current plot, will be of length
equal to the number of measurements, with the results placed in the
vector in order.

The measurement scale point(s) in `.measure` statements are also
saved in a vector, which is the scale for the result vector. If the
measurement name is ```result`'', then the scale vector is named
```result_scale`''. The scale contains one or two values,
depending on whether it is a point or interval measurement.

** Next:** Post-Measurement Commands
** Up:** The measure Command
** Previous:** Syntax Compatibility
** Contents**
** Index**
Stephen R. Whiteley
2019-03-16