# Model Check Parameters - MAXRATIO and EPSILON

I am doing certain model checks of my Ansys 2019 R1 setup and I would like to know how can I extract the following ("NASTRAN") parameters:

1) **The maximum ratio **which represents the ratio between the highest and the lowest term of the stiffness matrix. The value of the model shall be less than 1.0E7. (Modal Analysis)

2) The "**EPSILON" **value corresponds to the ratio of work done by residual loads vs. work done by external applied loads. The EPSILON ratio computed shall be less than 1.E-8. (Structural Analysis)

Is there a command I can add to extract these ratios?

Thank you!

## Comments

for 1 you should see something like in the solver output:

ratio of these two terms should give you the required max ratio.

For second question you can compare stabilization energy (https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v201/en/wb_sim/ds_stabil_energy.html) and strain energy (https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v201/en/wb_sim/ds_Strain_Energy.html) perhaps?

-Aniket

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@Peter_Mur @Aniket

Here is the definition of Nastran's Epsilon check, also known as...

To calculate this in ANSYS, you have to do the matrix math to calculate deltaP, then divide by the system energy to normalize it to get epsilon. I don't know how to do that.