## Name

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

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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).

</listitem>

## 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

plq_function

## Authors

`Mike Trienis`, University of British Columbia, BC, Canada