# Synopsis

PDX_MSGT gdx_LocateDeg1CurveCusps(long option, MDA_PTR gdx_db_ptr, double toler, double **cusps, long *numcusps)

# Purpose

Locate cusps of a degree 1 GDX curve.

# Description

This routine finds cusps (defined by an angular tolerance) which are located at the join of two linear segments of the degree 1 curve.

# Input

## option

### GDX_UNNORM

Return normalized parameter values for the cusps that must be unnormalized for evaluation.

## gdx_db_ptr

The GDX curve database pointer.

## toler

Cosine angle tolerance. The angle between two neighboring linear segments can be between 0 degrees (no cusp) and 180 degrees. It is considered a cusp if the cosine of the angle between the segments is less than toler.

# Output

## cusps

A 1D array containing the parameter values corresponding to cusps. The number of values in cusps is numcusps. The array cusps is allocated in this routine (but only if at least one cusp is found). It must be deallocated in the calling program when it is no longer needed.

## numcusps

The number of parameter values in the array cusps. These correspond to cusps.

# Return

          GDX_NOERR
          GDX_BADDATA
          Low level error return
          .fi