Merge pull request #38 from SteffenHaeussler/add_boolean_point_on_line

Add boolean_point_on_line module

README.md

@@ -75,6 +75,7 @@ Currently, the following modules have been implemented:
 - [bbox-polygon](https://github.com/diogomatoschaves/pyturf/tree/master/turf/bbox_polygon)
 - [bearing](https://github.com/diogomatoschaves/pyturf/tree/master/turf/bearing)
 - [boolean-point-in-polygon](https://github.com/diogomatoschaves/pyturf/tree/master/turf/boolean_point_in_polygon)
+- [boolean-point-on-line](https://github.com/diogomatoschaves/pyturf/tree/master/turf/boolean_point_on_line)
 - [center](https://github.com/diogomatoschaves/pyturf/tree/master/turf/center)
 - [centroid](https://github.com/diogomatoschaves/pyturf/tree/master/turf/centroid)
 - [destination](https://github.com/diogomatoschaves/pyturf/tree/master/turf/destination)

docs/source/modules/booleans.rst

@@ -7,3 +7,9 @@ boolean-point-in-polygon
 ------------------------
 
 .. autofunction:: turf.boolean_point_in_polygon
+
+
+boolean-point-on-line
+---------------------
+
+.. autofunction:: turf.boolean_point_on_line

turf/__init__.py

@@ -4,6 +4,7 @@
 from turf.bbox_polygon import bbox_polygon
 from turf.bearing import bearing
 from turf.boolean_point_in_polygon import boolean_point_in_polygon
+from turf.boolean_point_on_line import boolean_point_on_line
 from turf.center import center
 from turf.centroid import centroid
 from turf.destination import destination

turf/boolean_point_on_line/__init__.py

@@ -0,0 +1 @@
+from turf.boolean_point_on_line._boolean_point_on_line import boolean_point_on_line

turf/boolean_point_on_line/_boolean_point_on_line.py

@@ -0,0 +1,97 @@
+from typing import Dict, List, Sequence, TypeVar, Union
+from decimal import Decimal, getcontext
+from math import sqrt
+
+import numpy as np
+
+from turf.helpers import Feature, LineString, Point
+
+from turf.helpers import feature_collection, line_string, multi_line_string
+from turf.invariant import get_coords_from_features
+
+ctx = getcontext()
+ctx.prec = 28
+
+PointFeature = TypeVar("PointFeature", Dict, Feature, Point)
+LineFeature = TypeVar("LineFeature", Dict, Feature, LineString)
+
+
+def boolean_point_on_line(
+    point: PointFeature, line: LineFeature, options: Dict = {}
+) -> bool:
+    """
+    Returns True if a point is on a line else False.
+    Accepts a optional parameter to ignore the start and end vertices of the linestring.
+
+    :param point: {Point} GeoJSON Point
+    :param line: {LineString} GeoJSON LineString
+    :param options: Optional parameters
+        [options["ignoreEndVertices"]=False] whether to ignore the start and end vertices
+
+    :return: boolean True/False if point is on line
+    """
+    if not isinstance(options, dict):
+        options = {}
+
+    point_on_line = False
+
+    ignore_end_vertices = options.get("ignoreEndVertices", False)
+
+    point_coord = get_coords_from_features(point, ("Point",))
+    line_coords = get_coords_from_features(line, ("LineString",))
+
+    for i in range(len(line_coords) - 1):
+
+        if ignore_end_vertices:
+
+            # ignore if point_coord are the line start
+            if (i == 0) and (point_coord == line_coords[i]):
+                continue
+
+            # ignore if point_coord are the line end
+            if ((i + 1) == (len(line_coords) - 1)) and (
+                point_coord == line_coords[i + 1]
+            ):
+                continue
+
+        point_on_line = point_on_segment(
+            point_coord, line_coords[i], line_coords[i + 1]
+        )
+
+        if point_on_line:
+            break
+
+    return point_on_line
+
+
+def point_on_segment(
+    point: List, segment_start: List, segment_end: List, epsilon: float = 1.0e-14
+) -> bool:
+    """
+    Checks if a given point is on a line or not.
+
+    Since this is a comparison of floats, I use the Decimal module of python
+
+
+    :param point: Coordinates of a point
+    :param segment_start: Coordinates of the start line
+    :param segment_end: Coordinates of the line end
+    :return: bool
+    """
+
+    len_segment = Decimal(
+        sqrt(
+            pow(segment_end[0] - segment_start[0], 2)
+            + pow(segment_end[1] - segment_start[1], 2)
+        )
+    )
+
+    len_point_seg_1 = Decimal(
+        sqrt(pow(point[0] - segment_start[0], 2) + pow(point[1] - segment_start[1], 2))
+    )
+
+    len_point_seg_2 = Decimal(
+        sqrt(pow(segment_end[0] - point[0], 2) + pow(segment_end[1] - point[1], 2))
+    )
+
+    return abs(len_segment - len_point_seg_1 - len_point_seg_2) <= epsilon

turf/boolean_point_on_line/tests/false/LineWithOnly1SegmentIgnoreBoundary.geojson

@@ -0,0 +1,36 @@
+{
+  "type": "FeatureCollection",
+  "properties": {
+    "ignoreEndVertices": true
+  },
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Point",
+        "coordinates": [
+          0,
+          0
+        ]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "LineString",
+        "coordinates": [
+          [
+            0,
+            0
+          ],
+          [
+            3,
+            3
+          ]
+        ]
+      }
+    }
+  ]
+}

turf/boolean_point_on_line/tests/false/LineWithOnly1SegmentIgnoreBoundaryEnd.geojson

@@ -0,0 +1,36 @@
+{
+  "type": "FeatureCollection",
+  "properties": {
+    "ignoreEndVertices": true
+  },
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Point",
+        "coordinates": [
+          3,
+          3
+        ]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "LineString",
+        "coordinates": [
+          [
+            0,
+            0
+          ],
+          [
+            3,
+            3
+          ]
+        ]
+      }
+    }
+  ]
+}

turf/boolean_point_on_line/tests/false/LineWithOnly1SegmentIgnoreBoundaryEnd_inverse.geojson

@@ -0,0 +1,36 @@
+{
+  "type": "FeatureCollection",
+  "properties": {
+    "ignoreEndVertices": true
+  },
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Point",
+        "coordinates": [
+          -3,
+          -3
+        ]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "LineString",
+        "coordinates": [
+          [
+            0,
+            0
+          ],
+          [
+            -3,
+            -3
+          ]
+        ]
+      }
+    }
+  ]
+}

turf/boolean_point_on_line/tests/false/LineWithOnly1SegmentIgnoreBoundaryEnd_inverse_v2.geojson

@@ -0,0 +1,36 @@
+{
+  "type": "FeatureCollection",
+  "properties": {
+    "ignoreEndVertices": true
+  },
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Point",
+        "coordinates": [
+          -3,
+          -6
+        ]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "LineString",
+        "coordinates": [
+          [
+            0,
+            0
+          ],
+          [
+            -3,
+            -6
+          ]
+        ]
+      }
+    }
+  ]
+}

turf/boolean_point_on_line/tests/false/LineWithOnly1SegmentIgnoreBoundary_inverse.geojson

@@ -0,0 +1,36 @@
+{
+  "type": "FeatureCollection",
+  "properties": {
+    "ignoreEndVertices": true
+  },
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Point",
+        "coordinates": [
+          0,
+          0
+        ]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "LineString",
+        "coordinates": [
+          [
+            0,
+            0
+          ],
+          [
+            -3,
+            -3
+          ]
+        ]
+      }
+    }
+  ]
+}

turf/boolean_point_on_line/tests/false/LineWithOnly1SegmentIgnoreBoundary_inverse_v2 copy.geojson

@@ -0,0 +1,36 @@
+{
+  "type": "FeatureCollection",
+  "properties": {
+    "ignoreEndVertices": true
+  },
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Point",
+        "coordinates": [
+          0,
+          0
+        ]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "LineString",
+        "coordinates": [
+          [
+            0,
+            0
+          ],
+          [
+            0,
+            5
+          ]
+        ]
+      }
+    }
+  ]
+}

turf/boolean_point_on_line/tests/false/LineWithOnly1SegmentIgnoreBoundary_inverse_v2.geojson

@@ -0,0 +1,36 @@
+{
+  "type": "FeatureCollection",
+  "properties": {
+    "ignoreEndVertices": true
+  },
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Point",
+        "coordinates": [
+          0,
+          5
+        ]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "LineString",
+        "coordinates": [
+          [
+            0,
+            0
+          ],
+          [
+            0,
+            5
+          ]
+        ]
+      }
+    }
+  ]
+}