**Guide Section: Diagramming**

**EASAP Tree:** **USER INTERFACE** → **DIAGRAM LIST** → **DIAGRAM**

**CURVE** creates a curved line on a **DIAGRAM**.

A **CURVE** is specified by a series of points and a curve type.

A minimum of two points is required in the list to at least produce a straight line.

The following curve types are available via **Curve Type:**

- Bezier
- Bezier without corners
- B-Spline
- Catmull-Rom
- Closed Natural Cubic
- Natural Cubic

When using the first three curve types (Bezier, Bezier without corners and B-Spline), the curve drawn will not necessarily pass through all the points specified. However, curves drawn using the final three curve types (Catmull-Rom, Closed Natural Cubic and Natural Cubic) will pass through all points specified.

The use of **object references** in **Points:** referencing **LIST**'s containing X and Y coordinate values is a powerful way to define a **CURVE**. These **LIST**'s are typically generated using an **INTERLEAVE**.

CURVE | |
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Essential Parameters: | |

Points: | List of curve point coordinates: x1,y1,x2,y2,… At least two points are required. Object references and expressions are allowed |

Line Style: | Select LINE STYLE from list |

Optional Parameters: | |

Show if: | Logical expression, if FALSE then curve NOT shown, else default→TRUE |

Transform: | Select one or more TRANSFORM from list. Order selected is order applied. |

Curve Type: | Type of curve to be drawn (default→CATMULLROM, BEZIER, BEZIER WITHOUT CORNERS, BSPLINE, CLOSED NATURAL CUBIC, NATURAL CUBIC) |

Delimiter: | Character to delimit object references in Points: |