[TrilinosApplication] Enforce non-zeros values in graph when doing BtDBProductOperation during constraint computation

[loumalouomega]

📝 Description

This update introduces a critical improvement in the constraint computation process, specifically during the BtDBProductOperation. Previously, the computation faced failures in certain scenarios due to the absence of values within the graph. This was a consequence of Epetra's default behavior, which removes null values from the graph to conserve memory. While this approach is memory-efficient, it has been identified as a potential source of errors during assembly and the equation solving phases.

To address this issue, we have implemented a mechanism to enforce the presence of non-zero values in the graph during the BtDBProductOperation. This enhancement is aimed at preventing the computation failures by ensuring that the graph maintains the necessary values for a successful assembly and system solving process. By doing so, we enhance the robustness of the computation and eliminate the errors associated with missing graph values.

🆕 Changelog

• Enforce non-zeros values in graph when doing BtDBProductOperation during constraint computation

[loumalouomega]

@pooyan-dadvand , @roigcarlo can you take a look?

[loumalouomega]

Thanks @ddiezrod