The *Projected 2D Length* is* *the length of a polyline, only taking into account the (X,Y) coordinates of the vertices and omitting the Z coordinate.

*The Projected 2D Length* is the sum the 2D length of each segment of the polyline (a segment being defined as the line between two consecutive vertices)

Consider two consecutive vertices V_{1} and V2 with coordinates (X_{1}, Y_{1}, Z_{1}) and (X_{2}, Y_{2}, Z_{2}). The 2D length of this segment is given by:

√ (*(ΔX)*2+ *(ΔY)*2)

Where:

ΔX = Χ_{2} - Χ_{1}

ΔY = Υ_{2 }- Υ_{1}

The *Projected 2D Length* of the *Polyline* is calculated by adding the 2D length of the segments:

L_{p} = L_{1} + L_{2} + L_{3} + … + L_{v}

where:

L_{p} = The *Projected 2D Length* of the polyline.

L_{1}, ..., L_{v }= The 2D length of the segments.