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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. > > The first time you execute the cell, the assignment H = Subscript[H, 1] + Subscript[H, 2]; sets H to 110 + 90, which is 200. Then, Tanh[Subscript[200,1]] is what you get. The second time you execute the cell, H is 200, so Subscript[200,1] is set to 110 and Subscript[200,2] is set to 90. Then, H is set to 200 again. Now, Subscript[H,1] is Subscript[200,1] which equals 110, so you get Tanh. If you want to do these kinds of manipulations with Subscript, then I recommend that you give Subscript the HoldFirst attribute. Carl Woll Wolfram Research >A second execution, yields the correct answer: > >Tanh > >Is this a feature that I don't understand or a bug? > >