Jump to content
Geochemist's Workbench Support Forum

''Newton-Raphson didn't converge after 999 iterations'' Problem

Recommended Posts

Hello, when i try to analyse my samples i have an error ''Newton-Raphson didn't converge after 999 iterations...'' on 1 and 2 samples. For example when i try to calculate water type with SpecE8 I have same error for 1 and 2 samples, but 3 allright, its Sr-OH water in result. I have same errors in 1 and 2 samples when I try to calculate something else with SpecE8. Maby it problem with my data, or with calculation properties? I'll be very grateful for your help.


Link to comment
Share on other sites


GSS can use SpecE8 to calculate various secondary values based on the data provided in the spreadsheet. The program solves the problem with a numerical scheme that does not tolerate zero masses well. This is probably the issue with the two samples that failed. You can set the program to treat 0 value entries as no data. To enable this got to Analysis -> Options. You can also just remove the 0 value from the datasheet. For more information on calculation with SpecE8, you can refer to section 3.3 in the GWB Essentials User Guide. 

You can also investigate issues with a specific sample by launching a SpecE8 instant from GSS. Please see section 3.5 Launching SpecE8 and React in the GWB Essentials User Guide. 

Hope this helps,
Jia Wang
Aqueous Solutions LLC

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...