This is documentation for Mathematica 5, which was
based on an earlier version of the Wolfram Language.

 Further Examples: SparseArray Here are some rules suitable for constructing a sparse array. In[1]:= Here is a sparse array corresponding to rules. In[2]:= Out[2]= This constructs the same sparse array using one rule. In[3]:= Out[3]= In[4]:= Out[4]= This shows the ordinary representation of ss. In[5]:= Out[5]//MatrixForm= This yields a sparse array in which unspecified elements are taken to have value instead of . In[6]:= Out[6]//MatrixForm= The usual commands for matrices work with sparse arrays. In[7]:= Out[7]= In[8]:= Out[8]//MatrixForm= This constructs a sparse array representing a banded matrix. In[9]:= Out[9]= In[10]:= Out[10]//MatrixForm= The full form of a sparse array contains the necessary data stored in an efficient form. In[11]:= Out[11]//FullForm= Evaluating the next two commands displays the structure of bb. In[12]:= In[13]:= This shows the structure of another sparse array. In[14]:= This defines the function BlockDiagonalMatrix which creates a block diagonal matrix from a list of matrices. For another efficient implementation see the Further Examples for PadRight. In[15]:= Here are four matrices. In[16]:= Out[16]//MatrixForm= In[17]:= Out[17]//MatrixForm= In[18]:= Out[18]//MatrixForm= In[19]:= Out[19]//MatrixForm= Here is the block diagonal matrix constructed from the four matrices. In[20]:= Out[20]//MatrixForm= In[21]:=