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pythonsyntaxsyntax-errorpyomo

Error message in pyomo in dynamic variable definition

I am attempting to replicate the brachistochrone optimization from this article using pyomo. Unfortunately, I recive an error message due to invalid syntax. The piece of code is as follows: 

def f_x_definition_FLIGHT(model, i):
    return m.f_x_FLIGHT[i] == math.sqrt(2*g*m.y[i])*math.cos(m.angle[i])
m.f_x_FLIGHT = Constraint(m.N_notinitial rule = f_x_definition_FLIGHT)

The invalid syntax appears in the third line, in m.f_x_FLIGHT =...

I have also constructed the Y-axis dynamic variable as 

def f_y_definition_FLIGHT(model, i):
    return m.f_y_FLIGHT[i] == math.sqrt(2*g*m.y[i])*math.sin(m.angle[i])
m.f_y_FLIGHT = Constraint(m.N_notinitial rule = f_y_definition_FLIGHT)

And there is no issue there.

The dynamic functions are built as 

m.f_x_FLIGHT             = Var(m.N_notinitial, domain = Reals) 
m.f_y_FLIGHT             = Var(m.N_notinitial, domain = Reals)

So I am unable to find the reason why there is a syntax error there

Solution

  • In the end it was the lack of a comma behind m.N_notinitial; the code works fine if written asm.f_x_FLIGHT = Constraint(m.N_notinitial, rule = f_x_definition_FLIGHT)