Fix bug in lorentzian plot for spectroscopies

[andrea-pasquale]

Closes #741.
There was no error in the fit since also the table shows the correct fitted value, the problem was just a factor 10^9 in the plot.
It is possible to test the fit by simply running

qq fit <output_folder>

and to generate the new report

qq report <output_folder>

Checklist:

• Reviewers confirm new code works as expected.
• Tests are passing.
• Coverage does not decrease.
• Documentation is updated.
• Compatibility with Qibo modules (Please edit this section if the current pull request is not compatible with the following branches).
  • Qibo: master
  • Qibolab: main
  • Qibolab_platforms_qrc: main

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.44%. Comparing base (ddba2d3) to head (4d86289).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #742   +/-   ##
=======================================
  Coverage   96.44%   96.44%           
=======================================
  Files         108      108           
  Lines        7509     7509           
=======================================
  Hits         7242     7242           
  Misses        267      267           

Flag	Coverage Δ
unittests	96.44% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
src/qibocal/protocols/characterization/utils.py	96.65% <ø> (ø)

[igres26]

This makes the line appear correctly in qubit spectroscopy for me, but still for resonator spectroscopy at low power it did not appear. Could it be that it failed to fit? I don't even see the table with the fitted values when that is the case.

[andrea-pasquale]

This makes the line appear correctly in qubit spectroscopy for me, but still for resonator spectroscopy at low power it did not appear. Could it be that it failed to fit? I don't even see the table with the fitted values when that is the case.

When the fit fails you should not see both the table and the plot with the fit.
It seems weird to me, please share the report where the fitting does not appear.

[andrea-pasquale]

This makes the line appear correctly in qubit spectroscopy for me, but still for resonator spectroscopy at low power it did not appear. Could it be that it failed to fit? I don't even see the table with the fitted values when that is the case.

This has been addressed here 72873bb in #744 because the issue was similar.