Hey there,
I try to read in a white space seperated file as a cross section (XS) into QDOAS.
When my analysis window covers the entire wavelength range of the cross section, the file is found without problems.
However, if I select a lower bound of the analysis window larger than 305.645 nm (first wavelength were the XS is > 300), the reading in fails.
The issue seems to be related to the intensities: If I scale the XS values with factors <= 0.7 or >= 4, the file can be read in, while other factors lead to the same error:
The same problem occurs if I cut the XS to wavelengths >= 310 nm (ommiting the jump) and use a wavelength range starting at wavelengths >310 nm.
The cross section is a ring cross section multiplied with the wavelength, therefore the values are high compared to ‘normal’ cross sections.
Cross section files (as .txt) for different factors can be found at:
I tried the reading in with both the QDOAS versions 3.5.0 and 3.6.5.
Hi, I just tried the cross section (with different scaling factors) in a test configuration, and I can’t reproduce the problem. Could you share a full configuration (qdoas configuration file, cross sections, reference and input file, the minimum required to reproduce the error), and the steps you take that produce this error (can be via private e-mail if you prefer not to make it public)? I assume the error shows up when you choose “Run Analysis”?
Hey again, I am afraid my email did not reach you. A short version of the .xml file can now also be found in the shared directory above.
The error does actually not occour when running the analysis. If I run the analysis, there are just no fits done without any error being thrown, usually. However, If I chose “View cross sections” for the anaysis, the message “Not found!!!” shows up next to the cross section path:
Hi, thank you very much for providing the test case. I was able to reproduce the issue and find the cause (a 10 year-old bug which you have helped us identify!). Also my apologies for the delay, I was away on vacation.
I’ll try to publish a fixed version of QDOAS asap.
Hi Thomas,
thank you very much for digging into the problem.
I now tried to install version 3.6.7 into a new conda environment using
conda create -n qdoas_3_6_7 -c conda-forge qdoas
The installation works and does not throw any exceptions. I can also start qdoas, however, opening an existing .xml project file leads to qdoas crashing.
Do you have an idea what could be the issue?
Hmm, that’s unfortunate . I’ll ask my colleague who mostly takes care of qdoas on windows to look into it.
In the mean time, perhaps you can continue working with version 3.6.6, using the rescaled cross sections that avoid the bug? The previous bug occurred when cross section values were in the same range as the selected wavelength interval (i.e. around 320. in your case). If you avoid this from happening by rescaling as you figured out yourself, there should be no problem.
. I’ll ask my colleague who mostly takes care of qdoas on windows to look into it.