random() is crashing the simulator

[Wallacegromit]

Qucs 0.0.20 /pro/share/qucs/ex_stat_prj/verification_random_values.sch

Eqn:Eqn2 var_x="1" Export="yes" Eqn:Eqn3 value="random()" Export="yes" Eqn:Eqn1 seed="srandom(1)" Export="yes" .DC:DC1 Temp="26.85" reltol="0.001" abstol="1 pA" vntol="1 uV" saveOPs="no" MaxIter="150" saveAll="no" convHelper="none" Solver="CroutLU" .SW:SW1 Sim="DC1" Type="lin" Param="init" Start="1" Stop="10" Points="10"

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Output:

Starting new simulation on Mon 16. Jan 2023 at 13:09:13:480

creating netlist... done. Starting /usr/local/bin/qucsator

project location: modules to load: 0 factorycreate.size() is 0 factorycreate has registered: parsing netlist...

Errors occurred during simulation on Mon 16. Jan 2023 at 13:09:13:657 Aborted.

Errors and Warnings:

ERROR: Simulator crashed! Please report this error to qucs-bugs@lists.sourceforge.net

[felix-salfelder]

On Mon, Jan 16, 2023 at 05:11:30AM -0800, Wallacegromit wrote:

Qucs 0.0.20 /pro/share/qucs/ex_stat_prj/verification_random_values.sch

Eqn:Eqn2 var_x="1" Export="yes" Eqn:Eqn3 value="random()" Export="yes" Eqn:Eqn1 seed="srandom(1)" Export="yes" .DC:DC1 Temp="26.85" reltol="0.001" abstol="1 pA" vntol="1 uV" saveOPs="no" MaxIter="150" saveAll="no" convHelper="none" Solver="CroutLU" .SW:SW1 Sim="DC1" Type="lin" Param="init" Start="1" Stop="10" Points="10"

Crashes all the same for me, please fix it if you can.

The closest I got to random numbers in Qucs simulations is with Gnucsator.

input "netlist.txt":

Idc:I1 _net0 gnd I=".1" .SW:SW1 Sim="DC1" Type="lin" Param="swp" Start="10m" Stop="50m" Points="5" Eqn:Eqn3 value="aunif(0,1)" Export="yes" Eqn:Eqn1 swp="1" Export="yes" .DC:DC1 Temp="26.85" reltol="0.001" abstol="1 pA" vntol="1 uV" saveOPs="no" MaxIter="150" saveAll="no" convHelper="none" Solver="CroutLU" R:R1 _net0 gnd R="value"

output "dat file":

<indep swp 5> 0.01 0.02 0.03 0.04 0.05

-0.05736191 0.08874336 -277.938E-6 -0.07651821 0.02742623

All you need is "load path/to/f_random.so" from [1] in gnucsator.rc or added at the top of your netlist.txt. Perhaps f_random.cc (or a variant of it) should be shipped with Gnucsator, feel free to send a patch or discuss further.

https://git.savannah.gnu.org/cgit/gnucap/gnucap-plugins.git/log/?h=random

[Wallacegromit]

knowing that it was working before on previous version 0.0.19. I have used it to trace stats on filters using the precision of the components. I took values of components Cap = Co ( 1 + precision (random()-0.5+ nbIter 0 ) . doing a parameter sweep on nbiter ( 1 to n ) n:is the amount of samples I want. I was able to plot the cutoff frequencz variation due to component precision.

[felix-salfelder]

On Mon, Jan 16, 2023 at 11:44:17PM -0800, Wallacegromit wrote:

knowing that it was working before on previous version.

Look at the node allocation bug (a.k.a. "crash with newer glibc" or so.). This one might be similar.