Hi, Jirka!Jirka wrote: ↑Fri Jun 22, 2018 9:32 pmYou probably have errors in the input:

a. Position: this is not the depth, but the observation node number.

b. Weight: it should not be zero. If you put zero weight, the data point is not considered (unless you put zero weight on all data points and then they will be uniformly weighted.)

c. It is better not to place constraints in optimized parameters (unless the code goes into some unreasonable territory).

d. Before you run the optimization, make sure that the code actually converges, i.e., in the first run request only zero inverse iteration. Only once this run works well set the number of inverse iteration higher and do the optimization.

J.

When I use type 2 to do the parameter inversion, and fill the position column with the nodes number of the observation points, it'll pop up a message which is "The forth column of the record 120 must be smaller than or equal to number of observation nodes."

My question is that "the observation node number" you said before means the observation point's number which is lower than or equal to 10, or means the node number which is lower than or equal to the total number of the nodes (which is 141 in my model)? And if the former is right, is the numerical sequence of them 1,2,3...n from top to bottom?

Thank you!