Adjust sounding queries

bin/xmet-sounding-graph

@@ -0,0 +1,51 @@
+#! /usr/bin/env python3
+
+import argparse
+import cairo
+import shapely
+
+from xmet.db       import Database
+from xmet.sounding import Sounding
+from xmet.skew_t   import SkewTGraph, SkewTLegend
+
+IMAGE_WIDTH  = 800
+IMAGE_HEIGHT = 800
+
+GRAPH_WIDTH  = 800 - 128
+GRAPH_HEIGHT = 800 - 128
+
+parser = argparse.ArgumentParser(
+    description = 'Graph most recent valid sounding for location'
+)
+
+parser.add_argument('db',        help='XMET SQLite3 database')
+parser.add_argument('lat',       help='Latitude')
+parser.add_argument('lon',       help='Longitude')
+parser.add_argument('timestamp', help='Timestamp in YYYY-MM-DD HH:MM:SS (UTC)')
+parser.add_argument('output',    help='Output SVG file')
+
+args = parser.parse_args()
+
+db = Database.connect(args.db)
+
+location = shapely.Point(float(args.lon), float(args.lat))
+sounding = Sounding.valid_by_location(db, location, args.timestamp)
+
+print(f"Graphing {sounding.station} sounding at {sounding.timestamp_observed}")
+
+skew_t = SkewTGraph(GRAPH_WIDTH, GRAPH_HEIGHT)
+
+with cairo.SVGSurface(args.output, IMAGE_WIDTH, IMAGE_HEIGHT) as surface:
+    cr = cairo.Context(surface)
+
+    cr.set_source_rgb(1, 1, 1)
+    cr.rectangle(0, 0, IMAGE_WIDTH, IMAGE_HEIGHT)
+    cr.fill()
+
+    skew_t.draw(cr, 64, 64, sounding.samples)
+
+    cr.set_source_rgb(0, 0, 0)
+    cr.rectangle(64, 64, GRAPH_WIDTH, GRAPH_HEIGHT)
+    cr.stroke()
+
+    SkewTLegend.draw_for_graph(cr, skew_t, 64, 64)

lib/xmet/igra.py

@@ -114,9 +114,10 @@ class IGRAReader():
         sounding.station = match['id']
 
         date = datetime.datetime(
-            year  = int(match['year']),
-            month = int(match['month']),
-            day   = int(match['day'])
+            year   = int(match['year']),
+            month  = int(match['month']),
+            day    = int(match['day']),
+            tzinfo = datetime.UTC
         )
 
         timestamp         = date.astimezone(datetime.UTC)

lib/xmet/skew_t.py

@@ -112,6 +112,9 @@ class SkewTGraph():
         first = True
 
         for sample in samples:
+            if sample.pressure < 0 or sample.pressure is None:
+                continue
+
             if sample.pressure < PRESSURE_MIN:
                 break
 

lib/xmet/sounding.py

@@ -131,9 +131,9 @@ class Sounding(DatabaseTable):
                 xmet_sounding
             where
                 station = :station
-                and timestamp_released <= :timestamp
+                and timestamp_observed <= :timestamp
             order by
-                timestamp_released desc
+                timestamp_observed desc
             limit 1
         """
 
@@ -167,10 +167,10 @@ class Sounding(DatabaseTable):
             from
                 xmet_sounding
             where
-                timestamp_released <= :timestamp
+                timestamp_observed <= :timestamp
             order by
                 distance asc,
-                timestamp_released desc
+                timestamp_observed desc
             limit 1
         """.format(crs=COORD_SYSTEM)