Initial commit

bin/sps.py

@@ -0,0 +1,50 @@
+#!/usr/bin/python3
+
+"""
+SPS importing functions.
+
+And by SPS, we mean more or less any line-delimited, fixed-width record format.
+"""
+
+import builtins
+from parse_fwr import parse_fwr
+
+def int (v):
+	return builtins.int(float(v))
+
+def parse_line (string, spec):
+	"""Parse a line from an SPS file."""
+	names = spec["names"]
+	widths = spec["widths"]
+	normalisers = spec["normalisers"]
+	record = [ t[0](t[1]) for t in zip(normalisers, parse_fwr(string, widths)) ]
+	return dict(zip(names, record))
+
+def from_file(path, spec = None):
+	if spec is None:
+		spec = {
+			"names": [ "line_name", "point_number", "easting", "northing" ],
+			"widths": [ -1, 10, 10, -25, 10, 10 ],
+			"normalisers": [ int, int, float, float ]
+		}
+	else:
+		normaliser_tokens = [ "int", "float", "str", "bool" ]
+		spec["normalisers"] = [ eval(t) for t in spec["types"] if t in normaliser_tokens ]
+
+	records = []
+	with open(path) as fd:
+		cnt = 0
+		line = fd.readline()
+		while line:
+			cnt = cnt+1
+
+			if line == "EOF":
+				break
+
+			record = parse_line(line, spec)
+			if record is not None:
+				records.append(record)
+
+			line = fd.readline()
+
+	return records