Measuring after loading results caused crash of ngspice

[Michal Janik]

Hi everybody,
I have faced next problem. I did very long time simulation of transient circuit. The calculation takes several days. I stored the results into file and I later wanted to load them and measure some values from it. I created some small script to reconsruct the problem:

* error loading

.global gnd

v1 1 gnd dc 0 sin(0 1 1meg)
R1 1 gnd 1

.control
    tran 10n 100u

    let v_out = v(1)

    set specwindow=blackman
    fft v_out

    let db_out=db(mag(v_out))

    * this measurement works
    meas sp v1 max  db_out from=0.9meg to=1.1meg

    write results.res

    destroy all

    load results.res

    * this measurement crashed ngspice
    meas sp v1 max  db_out from=0.9meg to=1.1meg

.endc

Michal

[Holger Vogt]

Late, but hopefully not too late for somebody interested in this.

The output of the fft vout is a complex number. The write command then stores all data as complex numbers, also the frequency, which used to be real before fft. After loading, ngspice did not recognize that frequency was now also complex and thus crashed. A fix is uploaded to scope-inpcom-15.

Holger