variable definitions - Why can't I define vector v as having subscripted elements v_1, v_2, v

variable definitions - Why can't I define vector v as having subscripted elements v_1, v_2, v_3...?

I'm a very beginner in Mathematica 8 programming. While trying to play a little with tensor analysis I encountered a problem. How to define for example vector in such manner:

v={$v_1,v_2,v_3$}

For now I get the recursive definition, due to the situation in which the v variable is on the right-hand and left-hand sides.

Answer

You could also use something like OverVector, since

OverVector[v] = {Subscript[v,1],Subscript[v,2],Subscript[v,3]}

isn't recursive, and so won't cause problems.

This takes a bit more effort to input

Type Ctrl+& and then Esc vec Esc to enter directly

but if you're interested in the typeset forms it might be worth it.

Comments

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