Add stac_version to example, make file usage more robust, fix links in readme

Author: kylemann16

README.md

@@ -15,7 +15,8 @@ LiDAR or coincidence-matched imagery.
 
 - Examples:
   - [Example](examples/example-autzen.json)
-  - [PDAL to STAC Python script](pdal-to-stac.py)
+  - [PDAL to STAC Python script](examples/pdal-to-stac.py)
+  - [Environment](examples/environment.yml)
 - [JSON Schema](json-schema/schema.json)
 - [Changelog](./CHANGELOG.md)
 
@@ -32,7 +33,7 @@ LiDAR or coincidence-matched imagery.
 ### Schema Object
 
 A sequential array of Items that define the dimensions or channels of
-the point cloud, their types, and their sizes (in full bytes).
+the point cloud, their types, and their sizes (in full **bytes**).
 
 | Field Name | Type    | Description |
 | ---------- | ------- | -------------------------- |

examples/example-autzen.json

@@ -275,7 +275,7 @@
         "name": "ScanAngleRank",
         "position": 9,
         "stddev": 8.484304657,
-        "variance": 71.98342551
+        "variance": 71.9834255
       },
       {
         "average": 126.4052859,
@@ -364,5 +364,6 @@
   "stac_extensions": [
     "https://stac-extensions.github.io/pointcloud/v1.0.0/schema.json"
   ],
+  "stac_version": "1.0.0",
   "type": "Feature"
 }

examples/pdal-to-stac.py

@@ -1,10 +1,13 @@
 #!/usr/bin/env python
 
-# conda install -c conda-forge pdal gdal
+# conda env create -f environment.yml
+# conda activate stac-extensions-pointcloud
+# ./pdal-to-stac.py
 
 import sys
 import json
-import os
+from os import path
+from pathlib import Path
 import pdal
 
 filename = "https://github.com/PDAL/data/raw/master/autzen/autzen-classified.copc.laz"
@@ -67,7 +70,7 @@ def convertBBox(obj):
     output['geometry'] = stats['bbox']['EPSG:4326']['boundary']
 
 output['bbox'] = convertBBox(stats['bbox']['EPSG:4326']['bbox'])
-output['id'] = os.path.basename(filename)
+output['id'] = path.basename(filename)
 output['type'] = 'Feature'
 
 assets = {'data': {'href': filename}}
@@ -91,10 +94,12 @@ def convertBBox(obj):
 output['properties'] = properties
 output['assets'] = assets
 output['stac_extensions'] = ['https://stac-extensions.github.io/pointcloud/v1.0.0/schema.json']
+output['stac_version'] = '1.0.0'
 
 link = {'rel':'self',"href":filename}
 output['links'] = [link]
 
-with open('examples/example-autzen.json', 'w') as autzen_out:
+example_dir = Path(__file__).parent
+with open(example_dir/'example-autzen.json', 'w') as autzen_out:
     autzen_out.write(json.dumps(output, sort_keys=True, indent=2,
                                 separators=(',', ': ')))