Inverse Solution Doesn't Iterate

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Jirka
Posts: 4790
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Inverse Solution Doesn't Iterate

Post by Jirka » Wed May 29, 2019 9:53 pm

There was so many things wrong with your project that I will not list them here. I attach the file that I modified so that it actually works and you can find the changes that I made.

Note that your initial estimates of optimized parameters cannot be so far off that their one percent change (that's how gradients are calculated) produces no change in the fit. The program then does not know in which direction to go.

J.
Attachments
Work.rar
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casiorenbar7
Posts: 4
Joined: Wed May 22, 2019 8:58 pm
Location: USA

Re: Inverse Solution Doesn't Iterate

Post by casiorenbar7 » Tue Jun 04, 2019 2:51 pm

Jirka,
Thank you very much!

casiorenbar7
Posts: 4
Joined: Wed May 22, 2019 8:58 pm
Location: USA

Re: Inverse Solution Doesn't Iterate

Post by casiorenbar7 » Fri Jun 14, 2019 7:36 pm

Hi Jirka,

I'm simulating a control column. I have a 1m-long column packed with sandy loam soil (90 cm). I'm modeling the movement of one gene which is already present in the soil phase from the beginning so I know the concentration of the gene in the soil at day 0, week 6 and week 12 (end of the experiment). The water is flowing constantly in the column and has no trace of the gene. So I want to see how the gene is flushing out from the soil with the leachate. I also know the concentration of the gene in the liquid coming out of the column at different time points. I used the ka, kd, and kstr that you calculated in a previous file, but they are not working here. Please find attached the file. Any suggestion? Thanks!
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SLC-ermC.rar
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Jirka
Posts: 4790
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Inverse Solution Doesn't Iterate

Post by Jirka » Sat Jun 15, 2019 12:56 am

I suggest that you look at our CSIRO Tutorial eBook (https://www.pc-progress.com/Downloads/P ... 0_2018.pdf) for guidance on how to properly define your HYDRUS-1D project. I'm not going to do that for you. How can you expect that you will get solute leached out of the soil profile when there is none in it initially and none applied on the boundary?

You must be misunderstanding the purpose of this Discussion Forum. We have thousands of users and I would not have time for that.

J.

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