Hawth's Analysis Tools for ArcGIS

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 Summary

INTERSECT LINES (MAKE POINTS) TOOL
Input: two vector layers (lines and/or polygons)
Output: a point layer representing the points of intersection between the two line layers
Features:

• creates a point whereever a line from the first layer CROSSES a line from the second layer (not that two segments of lines that overlap precisely for any distance > 0 do not "cross" per se, and no point is created)
• allows the option of writing the attribute data from the first line/poly layer to the attribute table of the new point layer that is created

Limitations:

• the geometry rules that define what exactly is meant by two lines "crossing" are not necessarily what you might expect - it is recommended that you inspect the output of this tool carefully to determine if it has met your purpose
• the two layers MUST HAVE THE SAME PROJECTION, or you will get the error message "All geometries involved in this operation must have the same spatial reference"

[Click for larger view]

 Example

Figures A-D. The first example (A) shows a small segment of a roads layer. Figure B shows a simulated animal movement path through that area. The result of the Intersect Lines tool is shown in C: the green points represent the locations where the movement path crosses any of the roads. This is depicted more clearly in D, which is a zoomed in view of a few intersections.

 Help

Getting started. Check that the two line and/or polygon layers you are using have the same projection (spatial reference). If not, you will need to reproject one to match the other.

Which layer to specify first? It does not matter which layer you use as the "Line/poly layer" and which you use as the "Intersect line/poly layer" UNLESS you want to copy attributes to the output points. In this case the layer you specify as the "Line/poly layer" is the one from which attributes will be copied.