Re: Marking pivot elements in a matrix?

*To*: mathgroup at smc.vnet.net*Subject*: [mg74934] Re: Marking pivot elements in a matrix?*From*: dh <dh at metrohm.ch>*Date*: Thu, 12 Apr 2007 04:45:45 -0400 (EDT)*References*: <evhuev$34o$1@smc.vnet.net>

Hi, try this: FrameBox[ {2, 3}] // DisplayForm or: ButtonBox[{2, 3}, ButtonFrame -> "DialogBox"] // DisplayForm and: m=Table[Random[Integer,{0,9}],{4},{4}]; GridBox[m,ColumnLines\[Rule]{False,False,True}]//DisplayForm or: RowBox[{"(",GridBox[m,ColumnLines\[Rule]{False,False,True}], ")"}] //DisplayForm Daniel jackgold at umich.edu wrote: > Hi folks, > > I am writing notes for a class in which matrix manipulations > is a necessary and frequent task. At present, when I wish to pick an > entry of the matrix as a "pivot" I simply write "pivot > on {2, 3}". It would be nice to enclose the {2, 3} entry in a square or > circle to indicate it is the pivot entry. I am unable to do this. In > this same vein, I often have need to put a single vertical (horizontal) > line through the matrix. > Mathematica provides the means for putting vertical (horizontal) > lines in a matrix but it allows only the option of putting lines at > every column (row). I want to be more selective, say one line > just before the last column. (This is the standard way of indicating > that the last column is an augmentation to the original coefficient > matrix). > > Is there any reasonably simple way to do this? >