How to set the value of MINUSGRADIENT in parameters.py

[ZongfaWang]

I download the 2D checkers model from the new website https://drive.google.com/open?id=1ow3LTYEvNn55yGeIV56sqaW-wXC0MtYW, but when i run this model, there is a KeyError: 'MINUSGRADIENT' in the inversion process. I check the parameters.py file and find there isn't the parameter MINUSGRADIENT. So i want to know what is the meaning of this parameter and how to choose its value .
thanks!!!

[Jncheer]

I encountered the same problem, have you solved it?

[niyiyu]

In the file seisflows/workflow/inversion.py, PAR.MINUSGRADIENT works like this:

     if PAR.MINUSGRADIENT:
        optimize.save(dst, -solver.merge(parts))
    else:
        optimize.save(dst, solver.merge(parts))

Thus, add MINUSGRADIENT whatever you like in parameters.py such that it has the form of True or False may work.

For the latest version of SPECFEM 2D (7.0), I may try to add:

MINUSGRADIENT=0