Merge pull request #23 from iterorganization/allow-scientific-notation

Allow for scientific notation

Author: SBlokhuizen

tests/test_yaml_parser.py

@@ -91,3 +91,30 @@ def assert_tendencies_correct(tendencies):
     assert tendencies[6].duration == approx(2)
     assert tendencies[6].from_ == approx(8)
     assert tendencies[6].to == approx(0)
+
+
+def test_scientific_notation():
+    """Test if scientific notation is parsed correctly."""
+    waveforms = {
+        "waveform:\n- {type: linear, to: 1.5e5}": 1.5e5,
+        "waveform:\n- {type: linear, to: 1.5e+5}": 1.5e5,
+        "waveform:\n- {type: linear, to: 1.5E+5}": 1.5e5,
+        "waveform:\n- {type: linear, to: 1.5e-5}": 1.5e-5,
+        "waveform:\n- {type: linear, to: 1.5E-5}": 1.5e-5,
+        "waveform:\n- {type: linear, to: 1e5}": 1e5,
+        "waveform:\n- {type: linear, to: 1e+5}": 1e5,
+        "waveform:\n- {type: linear, to: 1E+5}": 1e5,
+        "waveform:\n- {type: linear, to: 1e-5}": 1e-5,
+        "waveform:\n- {type: linear, to: 1E-5}": 1e-5,
+        "waveform:\n- {type: linear, to: 0e5}": 0.0,
+        "waveform:\n- {type: linear, to: 0E0}": 0.0,
+        "waveform:\n- {type: linear, to: -1.5e5}": -1.5e5,
+        "waveform:\n- {type: linear, to: -1E+5}": -1e5,
+        "waveform:\n- {type: linear, to: -1.5e-5}": -1.5e-5,
+    }
+
+    yaml_parser = YamlParser()
+
+    for waveform, expected_value in waveforms.items():
+        yaml_parser.parse_waveforms(waveform)
+        assert yaml_parser.waveform.tendencies[0].to == expected_value

waveform_editor/yaml_parser.py

@@ -1,3 +1,5 @@
+import re
+
 import holoviews as hv
 import yaml
 
@@ -48,7 +50,24 @@ def parse_waveforms(self, yaml_str):
         """
         self.has_yaml_error = False
         try:
-            waveform_yaml = yaml.load(yaml_str, Loader=LineNumberYamlLoader)
+            loader = LineNumberYamlLoader
+            # Parse scientific notation as a float, instead of a string. For
+            # more information see: https://stackoverflow.com/a/30462009/8196245
+            loader.add_implicit_resolver(
+                "tag:yaml.org,2002:float",
+                re.compile(
+                    """^(?:
+                     [-+]?(?:[0-9][0-9_]*)\\.[0-9_]*(?:[eE][-+]?[0-9]+)?
+                    |[-+]?(?:[0-9][0-9_]*)(?:[eE][-+]?[0-9]+)
+                    |\\.[0-9_]+(?:[eE][-+][0-9]+)?
+                    |[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+\\.[0-9_]*
+                    |[-+]?\\.(?:inf|Inf|INF)
+                    |\\.(?:nan|NaN|NAN))$""",
+                    re.X,
+                ),
+                list("-+0123456789."),
+            )
+            waveform_yaml = yaml.load(yaml_str, Loader=loader)
 
             if not isinstance(waveform_yaml, dict):
                 raise yaml.YAMLError(