Hi,
I hope this will be easy.  I would like to make a constraint that includes a constant.  However, this constant depends on the results of calculations in the script, so it must be designated as a variable and not hard-coded as a value (e.g. '0.07').
I wrote the constraint which depends on the constant_variable, and HyPhy is treating the constant_variable like a parameter and optimizes it.  How can I designate this constant_variable so that it will remain constant?

For example:
constant_variable = parameter0;  /* Parameter0 is from a previous model and should not be optimized in the current model.*/
parameter1 := parameter2 + constant_variable * parameter3;

In this example I would only want the parameters 1, 2, and 3 to be optimized and 'constant_variable' should keep its value determined by the expression above.  (I cannot constrain 'constant_variable := parameter0', because it then tries to optimize 'parameter0'.)
I apologize if I am missing something obvious.  And thanks!