BUG
Concise problem statement:
Can't find a way to do a swept value of R1.
Trying to implement section 16.13.4.2 .step of ngspice manual:
http://www.ngspice.com/downloads/ngspice-manual.pdf
Note that spice netlist has lost indents for content of
.control .... .end
section. Don't know if that has any effect.
Note also that simulation runs OK as a simple non-swept sim and does not report errors.
.STEP R1 1k 2k 1k statement is commented out but has no effect if set to spice directive.
Steps to reproduce bug:
- Run transient simulation
Results: V(boo) only shown at 2.5V.
Expected results: V(boo) should be shown as 2.5V and 1.67V.
Url: https://easyeda.com/file_view_step-test-01_AysKEWevN.htm
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Although most of this bug report can be ignored now, there is still a problem.
There were several mistakes in my .control ... .end structure as I originally posted the circuit.
They have been fixed and the sim now runs through the expected 3 steps.
However, there remains a problem that only the results of the last step are shown as a transient simulation in the waveform display.
The parameters of that transient simulation are the ones set in the 'Run the Document' window and are not those defined by the 'tran 1u 1m' line inside the .control ... .end structure.
How to display all the stepped waveform results (for R1 = 1k, 2k, 3k)?