What does 'res_stat' field mean in residuals and why after the first SQP_RTI iteration it is always the same for different problem configurations

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Hi Alex,

res_stat is the infinity norm of the residual of the stationarity condition within the KKT conditions.
This residual is the sum of the gradient of the objective function and the weights of the multipliers times the gradients of the constraints.
The multipliers are initialized with zeros by default in acados.
Thus, what you report is expected behavior.

Cheers,
Jonathan

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