Function question (split from Ordinary differential equation)

[Niyilium]

I need someone to tell me what u(.,t) means when u is a function of x and t. x is in Rn 

 

 

Edited March 6, 2019 by Niyilium
Incomplete

[taeto]

It means the function defined on \(\mathbb{R}^n\) that maps \(x\) to \(u(x,t).\)

[HallsofIvy]

For example, if u(x, t)= x²+ t² then u(., t) is the function that takes 3 to the function u(3, t)= 9+ t², that takes 5 to u(5, t)= 25+ t², etc.  It maps a number to a function.

[Strange]

Is this the same as currying? (I have never seen this notation before .... )

[taeto]

1 hour ago, HallsofIvy said:

For example, if u(x, t)= x²+ t² then u(., t) is the function that takes 3 to the function u(3, t)= 9+ t², that takes 5 to u(5, t)= 25+ t², etc.  It maps a number to a function.

This is not an example of what I wrote . It also makes sense, but I cannot recall having seen it before.