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Re: Subscript Bug?
Aaron Fude wrote: > Hi, > > I have this code in a cell: > > Subscript[H, 1] = 110; Subscript[H, 2] = 90; > H = Subscript[H, 1] + Subscript[H, 2]; > Tanh[Subscript[H, 1]] > > The first time I execute the cell, I get > > Tanh[Subscript[200, 1]] > > which of course is nonsense. > > A second execution, yields the correct answer: > > Tanh > > Is this a feature that I don't understand or a bug? > Well I guess you should class it as a feature you don't understand! The first time though you make the following assignments: Subscript[H, 1] = 110 Subscript[H, 2] = 90 H0 The second time through, H has a value, so make the assignment: Subscript[200, 1] = 110 Subscript[200, 2] = 90 H0 Therefore on the second execution Subscript[200, 1] evaluates to 110. The moral of this story is that if you want to define Subscript[var,n], it doesn't make mush sense to proceed to give a value to var itself! David Bailey http://www.dbaileyconsultancy.co.uk