This is documentation for Mathematica 7, which was
based on an earlier version of the Wolfram Language.
 Parts of Matrices Mathematica provides several convenient methods for extracting and manipulating parts of matrices. The flexible [[ ]] (Part) and ;; (Span) syntaxes provide compact yet readable representations of operations on submatrices and matrix elements. Mathematica's symbolic character also allows convenient pattern and rule-based element specifications. Dimensions — dimensions of a matrix MatrixQ — test whether an expression is a matrix      Part — elements and submatrices: m[[i, j]]; resettable with m[[i, j]]=x Take — take rows, columns and submatrices Drop — drop rows, columns and submatrices Diagonal — get the list of elements on the diagonal RotateLeft, RotateRight — cyclically rotate rows or columns Reverse — reverse rows or columns Transpose — interchange rows and columns Join — join rows or columns of several matrices      Position — find positions where elements that match a pattern occur Extract — extract elements that appear at a list of positions ReplacePart — make replacements for collections of elements ArrayRules — get a list of positions and values for nonzero elements      Map — apply a function at any level TUTORIALS Vectors and Matrices Parts of Expressions Getting and Setting Pieces of Matrices Adding, Removing and Modifying List Elements Rearranging Nested Lists MORE ABOUT List Manipulation Parts of General Lists RELATED LINKS How to: Do Linear Algebra How to: Get Parts of a Matrix How to: Update Parts of a Matrix