# Synopsis

PDX_MSGT gdx_ExtractNurbIsoCurve(long option, T_GDX_NURB_SURF *sur, int model, double uv, void *gdx_cur)

# Purpose

Extract an iso-parametric curve from a GDX NURB Surface.

# Description

This routine extracts an iso-parametric curve from a GDX NURB Surface.

# Input

## option

### GDX_COMMIT

The entity creation option. If set, the GDX entity will be commited to the data base. Default is do not commit.

### GDX_UVALUE

If set, then uv is a u-value (isocurve is varying in v); otherwise, uv is a v-value (isocurve is varying in u).

## sur

The input surface from which a curve is to be extracted.

## model

The GDX model for entity creation.

## uv

A u- or v-value (see option). This defines which curve is to be extracted.

# Output

## gdx_cur

The extracted isocurve.

# Return

          GDX_NOERR
          Low level error return
          .fi