Synopsis

PDX_MSGT igeo_Eval110Derivs(long option, MDA_PTR db_ptr, IMTH_MATRIX matrix, double tval, int max_derivs, double (*derivs)[3])

Purpose

Evaluate derivatives on an IGES Line (110)

Description

At a given parameter value between 0.0 and 1.0 inclusive, evaluate derivatives on the IGES line entity. A max_derivs of 0 is equivalent to evaluating a point on the IGES line entity. The IGES line entity must be a valid IGES definition. A max_derivs value > 1 returns zero derivative values.

Input

option

IGES_NOMATRIX

Do not apply the entity matrix to the derivatives

db_ptr

The IGES 110 entity database pointer

matrix

The matrix to apply to the derivatives

tval

The parameter value to evaluate (0.0 - 1.0)

max_derivs

The maximium derivative required

Output

derivs

The 3D derivatives

Return

      IGEO_NOERR
      IGEO_INVALIDPARMVALUE
      Low level error return
      .fi