Re: Manipulate with Matrices

*To*: mathgroup at smc.vnet.net*Subject*: [mg113640] Re: Manipulate with Matrices*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Fri, 5 Nov 2010 05:14:28 -0500 (EST)

Perhaps something similar to this matrices = { IdentityMatrix[5], ConstantArray[1, {5, 5}], ConstantArray[a, {5, 5}]}; labels = CharacterRange["a", FromCharacterCode[ToCharacterCode["a"] + Length[matrices] - 1]]; Manipulate[ Column[{TraditionalForm[ Row[Thread[labels == matrices], ","]], "", "Det[" <> nn <> "] = " <> ToString[Det[matrices[[ Position[labels, nn][[1, 1]]]]]]}], {nn, labels}] Bob Hanlon ---- Jay <jaiezee at gmail.com> wrote: ============= I would like to use Manipulate on matrices. For instance, allow the user to choose elements of a 50 by 50 matrix, and Manipulate shows the dynamic inverse or transpose or determinant or whatever of the so manipulated matrix. But I do not wish to specify ranges for the 2500 elements separately, but rather using matrices as objects. For instance, I would like the user to choose a 5 by 5 matrix, whereby the range goes from the zero matrix to the matrix with all elements equal to 100, with initial matrix the identity matrix: Manipulate[ Det[nn], {{nn, IdentityMatrix[5]}, ConstantArray[0, {5, 5}], ConstantArray[100, {5, 5}]}] How can this be accomplished? How do I tell Mathematica that nn is a 5 by 5 matrix to start with? I would have hoped that the initial value shows it is a 5 by 5 matrix, but I think that does not work quite so automatically. In that sense, neither the following works, Manipulate[FullSimplify[Det[Array[nn, {5, 5}]]], {nn}] Any help much appreciated! Jay -- Bob Hanlon