GPX Waypoint Filter

A powerful Python script for filtering waypoints from GPX files based on multiple criteria including text matching, timestamps, and geographic boundaries.

Features

• Text-based filtering: Search waypoint names, symbols, and timestamps
• Geographic filtering: Filter by latitude/longitude bounding boxes
• Flexible logic: Combine criteria with AND/OR operations
• Fuzzy matching: Find partial text matches
• Duplicate removal: Automatically removes duplicate waypoints
• Preserves data: Maintains all original waypoint attributes

Installation

Requirements

• Python 3.6 or higher
• gpxpy library

Setup

# Install the required dependency
pip install gpxpy

# Make the script executable (optional)
chmod +x gpx_waypoint_filter.py

Basic Usage

python gpx_waypoint_filter.py input.gpx output.gpx [OPTIONS]

Command Line Options

Required Arguments

• input_file: Path to the input GPX file
• output_file: Path where filtered waypoints will be saved

Text Filtering Options

--name (multiple values allowed)

Filter waypoints where the name contains any of the specified strings.

--name trout salmon "golden pond"

--sym (multiple values allowed)

Filter waypoints where the symbol field contains any of the specified strings.

--sym fish camping "picnic area"

--time (multiple values allowed)

Filter waypoints where the timestamp contains any of the specified strings.

--time 2024 "2024-07" "August"

Geographic Filtering Options

--lat-min (decimal degrees)

Minimum latitude boundary (inclusive).

--lat-min 37.5

--lat-max (decimal degrees)

Maximum latitude boundary (inclusive).

--lat-max 38.0

--lon-min (decimal degrees)

Minimum longitude boundary (inclusive).

--lon-min -119.5

--lon-max (decimal degrees)

Maximum longitude boundary (inclusive).

--lon-max -118.5

Logic Control Options

--logic (choices: or, and, bounds-or, bounds-and)

Controls how different criteria groups are combined. Default: or

• or: Match ANY criteria (default)
• and: Match ALL specified criteria
• bounds-or: Geographic bounds AND with each other, then OR with text criteria
• bounds-and: Geographic bounds AND with each other, then AND with text criteria

--logic bounds-or

--bounds-logic (choices: and, or)

Controls how latitude and longitude bounds are combined. Default: and

• and: Waypoint must be within both lat AND lon bounds
• or: Waypoint must be within lat OR lon bounds

--bounds-logic or

Other Options

--case-sensitive

Enable case-sensitive text matching (default is case-insensitive).

--case-sensitive

--verbose or -v

Display detailed filtering information during processing.

--verbose

Common Usage Examples

1. Filter by Symbol

Find all waypoints with "fish" in the symbol field:

python gpx_waypoint_filter.py input.gpx output.gpx --sym fish

2. Filter by Multiple Names

Find waypoints containing any fishing-related terms in the name:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --name trout salmon bass pike "golden pond" brook

3. Geographic Bounding Box

Get all waypoints within a specific region:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 37.0 --lat-max 38.0 \
  --lon-min -119.5 --lon-max -118.5

4. Combine Geography and Text (AND)

Find camping spots within a specific region:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 37.0 --lat-max 38.0 \
  --lon-min -119.5 --lon-max -118.5 \
  --sym camping \
  --logic bounds-and

5. Combine Geography and Text (OR)

Get waypoints either in the region OR with fishing-related content:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 37.0 --lat-max 38.0 \
  --lon-min -119.5 --lon-max -118.5 \
  --sym fish --name trout \
  --logic bounds-or

6. Filter by Year

Find all waypoints from 2024:

python gpx_waypoint_filter.py input.gpx output.gpx --time 2024

7. Complex Multi-Criteria

Waypoints must be in region AND have "camp" in name AND be from 2024:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 37.0 --lat-max 38.0 \
  --lon-min -119.5 --lon-max -118.5 \
  --name camp \
  --time 2024 \
  --logic and

8. Latitude-Only Filtering

Get all waypoints between certain latitudes (any longitude):

python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 35.0 --lat-max 40.0

9. Case-Sensitive Search

Find waypoints with exact case match:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --name "Eagle Lake" "Bear Creek" \
  --case-sensitive

10. Multiple Symbol Types

Find waypoints with various outdoor activity symbols:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --sym camping fishing hiking "scenic viewpoint" swimming

Advanced Examples

Fishing Spots in Multiple Regions

Find fishing locations in either of two regions:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 37.0 --lat-max 37.5 \
  --lon-min -119.5 --lon-max -119.0 \
  --sym fish \
  --logic bounds-and \
  --bounds-logic or

High Sierra Lakes

Find lakes above a certain latitude with specific names:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 37.5 \
  --name lake pond reservoir "alpine lake" \
  --logic and

Recent Waypoints in Region

Waypoints from 2023-2024 within bounds:

python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 36.5 --lat-max 38.5 \
  --lon-min -120.0 --lon-max -118.0 \
  --time 2023 2024 \
  --logic bounds-and

Logic Mode Examples

Understanding --logic or (default)

Any single criteria matches:

# Matches if: has "camp" OR has "fish" OR in bounds
python gpx_waypoint_filter.py input.gpx output.gpx \
  --name camp --sym fish \
  --lat-min 37.0 --lat-max 38.0

Understanding --logic and

All specified criteria must match:

# Matches if: has "camp" AND has "fish" AND in bounds
python gpx_waypoint_filter.py input.gpx output.gpx \
  --name camp --sym fish \
  --lat-min 37.0 --lat-max 38.0 \
  --logic and

Understanding --logic bounds-or

Bounds are evaluated together, then OR'd with text:

# Matches if: (in lat bounds AND in lon bounds) OR has "camp" OR has "fish"
python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 37.0 --lat-max 38.0 \
  --lon-min -119.0 --lon-max -118.0 \
  --name camp --sym fish \
  --logic bounds-or

Understanding --logic bounds-and

Bounds are evaluated together, then AND'd with text:

# Matches if: (in lat bounds AND in lon bounds) AND (has "camp" OR has "fish")
python gpx_waypoint_filter.py input.gpx output.gpx \
  --lat-min 37.0 --lat-max 38.0 \
  --lon-min -119.0 --lon-max -118.0 \
  --name camp --sym fish \
  --logic bounds-and

Tips and Best Practices

1. Start broad, then narrow: Test with lenient criteria first, then add restrictions
2. Use verbose mode: Add -v to see what's being filtered
3. Partial matches work: Searching for "camp" will match "camping", "campground", "basecamp"
4. Combine criteria thoughtfully: Understanding the logic modes helps create precise filters
5. Check your bounds: Latitude increases going north, longitude increases going east
6. Remember decimal degrees:
   • Latitude: -90 to +90 (negative = south)
   • Longitude: -180 to +180 (negative = west)

Troubleshooting

No waypoints in output

• Check if criteria are too restrictive
• Use --verbose to see filtering details
• Try broader search terms or larger geographic bounds
• Verify logic mode is appropriate for your query

Too many waypoints in output

• Add more specific criteria
• Switch from --logic or to --logic and
• Use exact phrases with --case-sensitive
• Narrow geographic bounds

Script errors

• Ensure input file exists and is valid GPX format
• Check that gpxpy is installed: pip install gpxpy
• Verify Python version is 3.6 or higher: python --version

Example Workflow

Filtering a large GPX file for a fishing trip:

# Step 1: See all fishing-related waypoints
python gpx_waypoint_filter.py all_waypoints.gpx fishing_spots.gpx \
  --sym fish --name trout bass salmon -v

# Step 2: Narrow to specific region
python gpx_waypoint_filter.py all_waypoints.gpx regional_fishing.gpx \
  --sym fish --name trout bass salmon \
  --lat-min 37.2 --lat-max 37.8 \
  --lon-min -119.3 --lon-max -118.7 \
  --logic bounds-and

# Step 3: Filter for recent visits only
python gpx_waypoint_filter.py regional_fishing.gpx recent_fishing.gpx \
  --time 2024

# Step 4: Find specific type with exact name
python gpx_waypoint_filter.py all_waypoints.gpx exact_spots.gpx \
  --name "Golden Trout Lake" --case-sensitive

License

This script is provided as-is for personal and commercial use.

Contributing

Feel free to suggest improvements or report issues with the script.