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Indeed, the new Expression Builder has made expression creation much easier, but are you still wishing for some more enhancements and handy features available right under it? Would it make working with expressions much quicker and easier if you have an option to evaluate or plot them from within the Expression Builder, just like the way you do with the Calculator. So, here your wish comes true with the new evaluation and plot options accessible within Expression Builder!

The Expression Builder now includes a new Eval/Plot button that brings up a tiny form with the evaluation and plotting options. 

You can use this form to plot or evaluate an expression from any test, corner, point, or history that you have run. After evaluation, output waveforms are plotted in the graph window and scalar results are displayed in the Expression Builder buffer or you can also send them to a table. You can also control the plotting mode using this form. 

Evaluating Expressions Using the Expression Builder

Let us understand this with the help of an example. Consider a simulation run with 3 design points, 2 corners and a nominal corner. This example illustrates how you can evaluate or plot the expression for an existing output, Swing. 

If you open the Expression Builder from the existing output it will open with the Swing expression in the buffer.  

As we’ve already run the simulation, all the 3 points are available in the Points drop-down list, and the 2 corners + nominal are shown in the Corner drop-down list as shown in the figures below.

Now, if you select point 1 and corner C1, and click the Eval/Plot button, the expression gets evaluated for the selected point, corner, history and test. In this case, output is a scalar value, therefore, it is displayed in the buffer.

You can also click the table button to append values for each of the points or corners in a table. In the figures below, notice that the correct values have been found for each design point or corner.

Plotting Expressions Using the Expression Builder

To plot a waveform result, just use the Plot button available in the form. It is easy to append waveforms from different design points or corners to compare them by selecting Append from the drop-down. For example, the waveforms below appear when you plot the expression for the flip function and append waveforms for other points and corners.

If you would like to watch these steps in detail, you can view the Expression Builder - Plot and Evaluation video on Cadence Online Support Click the video link now or visit Cadence Online Support and search for the video under Video Library.   

Note: If you don’t have a Cadence Online Support account, you can play the Expression Builder - Plot and Evaluation video (mp4) natively in Cadence Help when you are using Virtuoso IC6.1.7/ ICADV12.3 (ISR8 or later). In the Cadence Help Virtuoso Documentation Library, look for the video title under Video Demos. 

Related Resources

• Virtuoso ADE Explorer User Guide

  • Virtuoso ADE Explorer User Guide

• Video
  • Expression Builder in ADE Assembler & Explorer Video

• RAK
  • Expression Builder RAK

Note: For more information on Cadence circuit design products and services, visit www.cadence.com.

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 Arja Hunkin