how to find Nash, RMSE and R square of my model

i have created rainfall runoff model in simulink, now i need to calculate Nash, RMSE and R square for my model in simulink. what tool i have to use.

Answer 1

[Manas Meena]

You can either calculate the RMSE manually

y = <simulated data>
yhat = <experimental data>
RMSE = sqrt(mean((y - yhat).^2));

or you can refer to this RMSE function