CLI option to specify strings that are to be interpreted as NaN values (

#357)

* CLI option to specify strings that are to be interpreted as NaN values

Signed-off-by: F.N. Claessen <felix@seita.nl>

* Changelog entry

Signed-off-by: F.N. Claessen <felix@seita.nl>

documentation/changelog.rst

@@ -11,6 +11,7 @@ New features
 -----------
 * Three new CLI commands for cleaning up your database: delete 1) unchanged beliefs, 2) NaN values or 3) a sensor and all of its time series data [see `PR #328 <http://www.github.com/FlexMeasures/flexmeasures/pull/328>`_]
 * Add CLI option to pass a data unit when reading in time series data from CSV, so data can automatically be converted to the sensor unit [see `PR #341 <http://www.github.com/FlexMeasures/flexmeasures/pull/341>`_]
+* Add CLI option to specify custom strings that should be interpreted as NaN values when reading in time series data from CSV [see `PR #357 <http://www.github.com/FlexMeasures/flexmeasures/pull/357>`_]
 * Add CLI commands ``flexmeasures add sensor``, ``flexmeasures add asset-type``, ``flexmeasures add beliefs`` (which were experimental features before). [see `PR #337 <http://www.github.com/FlexMeasures/flexmeasures/pull/337>`_]
 * Add CLI commands for showing data [see `PR #339 <http://www.github.com/FlexMeasures/flexmeasures/pull/339>`_]
 * Add CLI command for attaching annotations to assets: ``flexmeasures add holidays`` adds public holidays [see `PR #343 <http://www.github.com/FlexMeasures/flexmeasures/pull/343>`_]

flexmeasures/cli/data_add.py

@@ -358,6 +358,12 @@ def add_initial_structure():
     type=int,
     help="Number of rows to skip from the top. Set to >1 to skip additional headers.",
 )
+@click.option(
+    "--na-values",
+    required=False,
+    multiple=True,
+    help="Additional strings to recognize as NaN values. This argument can be given multiple times.",
+)
 @click.option(
     "--nrows",
     required=False,
@@ -415,6 +421,7 @@ def add_beliefs(
     resample: bool = True,
     allow_overwrite: bool = False,
     skiprows: int = 1,
+    na_values: List[str] = None,
     nrows: Optional[int] = None,
     datecol: int = 0,
     valuecol: int = 1,
@@ -478,6 +485,7 @@ def add_beliefs(
         nrows=nrows,
         usecols=[datecol, valuecol],
         parse_dates=True,
+        na_values=na_values,
         **kwargs,
     )
     if unit is not None: