Talk:Time derivative

Notational dispute
I dispute the sentence "Other shorthands include a subscripted t as in xt." While subscript notation can be used to refer to derivatives, I've never seen it used for a time derivative. The reason is that the notation xt is discrete-time notation for the level (not change) of x at time t.

Unless someone objects, I will delete this sentence. Please respond pro or con. Duoduoduo (talk) 19:46, 4 July 2010 (UTC)