Label | Explanation | Data Type |

Input Features | The input line features that will be simplified. | Feature Layer |

Output Feature Class | The simplified output line feature class. It will contain all the fields from the input feature class. The output line feature class is topologically correct. The tool does not introduce topology errors, but topological errors in the input data will be flagged in the output line feature class. The output feature class will include the InLine_FID and SimLnFlag fields to contain the input feature IDs and the input topological errors, respectively. A SimLnFlag value of 1 indicates that an input topological error is present; a value of 0 (zero) indicates that no input error is present. | Feature Class |

Simplification Algorithm | Specifies the line simplification algorithm that will be used. - Retain critical points (Douglas-Peucker)—Critical points that preserve the essential shape of a line will be retained, and all other points will be removed (Douglas-Peucker). This is the default.
- Retain critical bends (Wang-Müller)—Critical bends will be retained, and extraneous bends will be removed from a line (Wang-Müller).
- Retain weighted effective areas (Zhou-Jones)—Vertices that form triangles of effective area that have been weighted by triangle shape will be retained (Zhou-Jones).
- Retain effective areas (Visvalingam-Whyatt)—Vertices that form triangles of effective area will be retained (Visvalingam-Whyatt).
| String |

Simplification Tolerance | The degree of simplification that will be used. You can choose a preferred unit; otherwise, the units of the input will be used. The MinSimpTol and MaxSimpTol fields will be added to the output to store the tolerance that was used when processing occurred. - For the Retain critical points (Douglas-Peucker) algorithm, the tolerance is the maximum allowable perpendicular distance between each vertex and the newly created line .
- For the Retain critical bends (Wang-Müller) algorithm, the tolerance is the diameter of a circle that approximates a significant bend.
- For the Retain weighted effective areas (Zhou-Jones) algorithm, the square of the tolerance is the area of a significant triangle defined by three adjacent vertices. The further a triangle deviates from equilateral, the higher weight it is given, and the less likely it is to be removed.
- For the Retain effective areas (Visvalingam-Whyatt) algorithm, the square of the tolerance is the area of a significant triangle defined by three adjacent vertices.
| Linear Unit |

Resolve topological errors (Optional) | ## Legacy:This is a legacy parameter that is no longer used. It was formerly used to indicate how topological errors, possibly introduced during processing, were resolved. This parameter is still included in the tool's syntax for compatibility in scripts and models but is hidden from the Geoprocessing pane. | Boolean |

Keep collapsed points (Optional) | Specifies whether an output point feature class will be created to store the endpoints of lines that are smaller than the spatial tolerance. The point output is derived; it will use the same name and location as the Output Feature Class parameter value but with a _Pnt suffix. - Checked—A derived output point feature class will be created to store the endpoints of collapsed zero length lines. This is the default.
- Unchecked—A derived output point feature class will not be created.
| Boolean |

Check for topological errors (Optional) | ## Note:This is a legacy parameter that is no longer used. It was formerly used to indicate how topological errors, possibly introduced during processing, were handled. This parameter is still included in the tool's syntax for compatibility in scripts and models but is hidden from the Geoprocessing pane. | Boolean |

Input Barrier Layers
(Optional) | Inputs containing features to act as barriers for simplification. Resulting simplified lines will not touch or cross barrier features. For example, when simplifying contour lines, spot height features input as barriers ensure that the simplified contour lines will not simplify across these points. The output will not violate the elevation as described by measured spot heights. | Feature Layer |

Handling Topological Errors (Optional) | Specifies how topological errors will be handled. Topological errors may be introduced in the simplification process and can include lines crossing or overlapping lines. - Do not check for topological errors—Topological errors will not be identified. This is the default.
- Flag topological errors—Topological errors will be flagged.
- Resolve topological errors—Topological errors will be resolved.
| String |

### Derived Output

Label | Explanation | Data Type |

Lines Collapsed To Zero Length | When the Keep collapsed points parameter is checked, an output point feature class is created to store the endpoints of lines that are smaller than the spatial tolerance of the data. | Feature Class |