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Hello everyone,

I just started working with swwm 5.1 and I'l already stuck... I try a very simple model to understand how the software works and I can't run anything at all.

Here is the example I'm working on (in fact it's simply the tutorial proposed by EPA)


When I try to compile it, I received the error message:

  ERROR 211: invalid number 0,80 at line 31 of [OPTION] section:  VARIABLE_STEP

However, no matter what I change in the option panel, I can't solve this error. It is said in the documentation that such an error is a wrong number format (negative number for instance).

As it is a by default value I just don't know what to do.

Does anyone has an idea how to proceed?

Thanks in advance,



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    • Hello Robert,

      Thanks for your answer. I thought also that it could be the answer.

      The problem is that I cannot change it in the option panel, I have to enter percentage (80 %) and the software changes it in 0,80.

      Maybe a problem in the code? I already uninstall/install to try to fix the problem but it didn't work.

      Any idea how I could change it?




      • Hi, Can you you send me your model to so I can take a look?

        • Done,Thanks a lot.

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