%% MatrixMarket matrix coordinate double general
% This example is 1-based with (optional) nnz
%
% This is a 1D mass matrix
%
%              1        
%              .        
%             / \       
%            /   \ 0    
%  phi_i  --o  o  o--o--
%              i  j     
%
%                 1     
%                 .     
%                / \    
%               /   \ 0 
%  phi_j  --o--o  o  o--
%              i  j     
%
%                i     j
%            | i_ii  i_ij | i
%  inertia = |            |
%            | i_ji  i_jj | j
%
%  distance(i, j) = d = 1.
%
%  i_ii = int_[i,j](phi_i.phi_i) = int_[i,j]((1-x)(1-x)) = i_jj (area under the curve)
%  i_ij = int_[i,j](phi_i.phi_j) = int_[i,j]((1-x)   x ) = i_ji
%  i_ji = int_[i,j](phi_j.phi_i) = int_[i,j](   x (1-x)) = d*1./6.
%  i_jj = int_[i,j](phi_j.phi_j) = int_[i,j](   x    x ) = d*1./3.
%
% B <=> mass assembly
%
% n m [nnz]
% i j Bij

8 8 22

1  1  0.333
2  2  0.333
3  3  0.333
4  4  0.333
5  5  0.333
6  6  0.333
7  7  0.333
8  8  0.333

2  1  0.166
3  2  0.166
4  3  0.166
5  4  0.166
6  5  0.166
7  6  0.166
8  7  0.166

1  2  0.166
2  3  0.166
3  4  0.166
4  5  0.166
5  6  0.166
6  7  0.166
7  8  0.166