Civil 3D Survey : Tip : Least Square analysis error message "System error : could not invert matrix" workaround

In some cases when performing LSA solvation fails or produces some, not all, abnormal ellipsis errors.
I get a message "System error:could not invert matrix".

In this case you must not perform the analysis in one step through "Perform analysis...".

You can do it step by step.

First "Create input file"

Then "Edit input file".
Propably there will be some "Distance std error" that have no sense.
You can manually set them to a logical value.
For example i had automatically generated, some not all, values of...500000000000000.0000 (!!!) and i changed them to 0.0050.

Then save the altered file.

Finally "Process input file". Now it will propably produce no error messages and error ellipsis will be normal.

Survey database is not automatically informed if used those steps. So for the results to reflect in drawing and data a final step is required "Update survey database".

Remember that before all those steps if there is a previous not adequate adjustment it should be first reset.

Not only user must learn how to use properly the software but must burn his mind to find workarounds.

Too many hours lost in learning, testing, exploring options and searching for workarounds.