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### how to define the codomain of a symbolic function

Hi, I'm perfoming some basic differential calculations in General Relativity.

I defined a function a(t), where t is one of the chart coordinates: a = function('a')(t) #only metric function

Then I'm calculating stuff like Cristoffel symbols, Einstein equations, etc.

This function appears to be a complex one (i.e. I see the bar over it sometimes - complex conjugate). This is boring since the calculations does not simplify by themselves.

Is there a way to "assume" that the codomain of the function are the Real Numbers? It would be great also to specify only a range, like (0,+\infty).

Thanks

### how to define the codomain of a symbolic function

Hi, I'm perfoming some basic differential calculations in General Relativity.

I defined a function a(t), where t is one of the chart coordinates: a = function('a')(t) #only metric functioncoordinates:

Then a = function('a')(t)

I do not want to define how it depends on t since I'm calculating stuff like Cristoffel symbols, Einstein equations, etc.etc and I want to keep the resulting formulas independent from the functional behaviour of a(t).

This function appears to be a complex one (i.e. I see the bar over it sometimes - complex conjugate). This is boring since the calculations does not simplify by themselves.

Is there a way to "assume" that the codomain of the function are the Real Numbers? It would be great also to specify only a range, like (0,+\infty).

Thanks

### how to define the codomain of a symbolic function

Hi, I'm perfoming some basic differential calculations in General Relativity.

I defined created a function a(t), where t is one of the chart coordinates:

a = function('a')(t)

I do not want to define how it depends on t since I'm calculating stuff like Cristoffel symbols, Einstein equations, etc and I want to keep the resulting formulas independent from the functional behaviour of a(t).

This function appears to be a complex one (i.e. I see the bar over it sometimes - complex conjugate). This is boring since the calculations does not simplify by themselves.

Is there a way to "assume" that the codomain of the function are the Real Numbers? It would be great also to specify only a range, like (0,+\infty).

Thanks