**BUG**
Concise problem statement:
There are some cases where the way units are displayed in WaveForm will confuse users.
I have put some simulations in the folder:
**New WaveForm Test**
to try to show examples of how WaveForm presents trace information.
To summarise:
1) If the user multiplies or divides a trace by a number or a parameter, then there are no units shown.
The units of the scaled trace (V, A, etc.) shown in WaveForm should be the same as for the original unscaled trace.
2) If the user multiplies two or more voltages (or currents), then there are no units shown.
The units of the scaled trace shown in WaveForm should be shown as V^2 (or A^2) squared (or V^3, I^3 etc., if necessary).
3) Multiplying a voltage by a current correctly displays power in W. Dividing a voltage by a current or a current by a voltage displays the correct units (i.e. Ohms or Mhos).
Can (1) and (2) be made so that the units are correct (i.e. what the user would expect to see)?
Examples:
https://easyeda.com/editor#id=JB6CUO6oG
No Y axis units for probe when multiplied by number.
If a trace is multiplied or divided by a number directly or using `let` and then displayed using probe, there are no Y axis units shown. This is not correct.
https://easyeda.com/editor#id=TLha4mgyQ
Y axis units for probe when multiplied by parameter.
If a trace is multiplied by another voltage in the circuit or by a parameter directly or using `let` and then displayed using probe, the Y axis shows units.
However, multiplying two voltage together does **not** show as V^2 on the Y axis. This is not correct.
https://easyeda.com/editor#id=UB7pjBvN5
No Y axis units for probe when dividing
If a trace is divided by a number, a parameter or a voltage either directly or using `let` and then displayed using probe, there are no Y axis units shown.
It is to be expected that dividing a voltage by a voltage gives a unitless result but dividing a voltage by a unitless number or parameter should give a voltage result.
https://easyeda.com/editor#id=a2WQK2jBv
Examples of correct derived units display.
These examples display the correct derived units.
An offset sinusoid is used to avoid error messages due to divide by zero at the zero crossings.
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