<< plq_check plq plq_co >>

CCA (Computational Convex Analysis) >> plq > plq_clean

plq_clean

Piecewise linear quadratic (plq), clears duplicate rows

Calling Sequence

[plqClean] = plq_clean(plqDirty)

Parameters

plqDirty

matrix. A plq function with dimensions n x 4.

plqClean

matrix. A plq function with dimensions n x 4.

Description

The plq_clean function is used to help clear duplicate rows which arise during the plq fenchel conjugate operation. For example, the function reduces the number of rows by merging these two pieces of a plq function into one e.g. [0,1,0,0;0,1,0,0] -> [0,1,0,0]. The function also compresses duplicate point values e.g. [0,1,0,1;0,2,0,0] -> [0,1,0,1], and merges adjacent rows that are always infinite (which arise in plq_add).

This algorithm runs in O(n) time, where n is the number of pieces in plqf.

Examples

// Example 1. Clear Duplicate Points
plqDirty=[0,1,0,0;0,2,0,0;1,2,3,4;%inf,3,0,0];
plqClean=plq_clean(plqDirty);
// plqClean == [0,1,0,0;1,2,3,4;%inf,3,0,0];

// Example 2. Clear Duplicate Rows
plqDirty=[0,1,0,0;0,1,0,0;1,2,3,4;%inf,3,0,0];
plqClean=plq_clean(plqDirty);
// plqClean == [0,1,0,0;1,2,3,4;%inf,3,0,0];

// Example 3. Clear Duplicate Infinites
plqDirty = [-1  ,  0,  -1, %inf; ...
            -0.5,  0,   1, %inf; ...
             0  ,  0,   1, 1   ; ...
             0.5,  0,  -1, 1   ; ...
             1  ,  0,  -1, %inf; ...
            %inf,  0,   1, %inf];
plqClean = plq_clean(plqDirty);
// plqClean == [-0.5,  0,  0, %inf; ...
//               0  ,  0,  1, 1   ; ...
//               0.5,  0, -1, 1   ; ...
//              %inf,  0,  0, %inf];

See Also

Authors

Mike Trienis, University of British Columbia, BC, Canada


Report an issue
<< plq_check plq plq_co >>