Add bowtie

Author: tukiains

cloudnetpy/instruments/__init__.py

@@ -1,4 +1,5 @@
 from .basta import basta2nc
+from .bowtie import bowtie2nc
 from .ceilo import ceilo2nc
 from .copernicus import copernicus2nc
 from .disdrometer import parsivel2nc, thies2nc

cloudnetpy/instruments/bowtie.py

@@ -0,0 +1,95 @@
+from os import PathLike
+
+from cloudnetpy import output
+from cloudnetpy.constants import G_TO_KG, MM_H_TO_M_S
+from cloudnetpy.instruments.instruments import FMCW94
+from cloudnetpy.instruments.nc_radar import NcRadar
+from cloudnetpy.metadata import MetaData
+
+
+def bowtie2nc(
+    bowtie_file: str | PathLike,
+    output_file: str,
+    site_meta: dict,
+    uuid: str | None = None,
+    date: str | None = None,
+) -> str:
+    """Converts data from 'Bowtie' cloud radar on RV-Meteor into
+       Cloudnet Level 1b netCDF file.
+
+    Args:
+        bowtie_file: Input filename.
+        output_file: Output filename.
+        site_meta: Dictionary containing information about the site. Required key
+            value pair is `name`. Optional are `latitude`, `longitude`, `altitude`.
+        uuid: Set specific UUID for the file.
+        date: Expected date as YYYY-MM-DD of all profiles in the file.
+
+    Returns:
+        UUID of the generated file.
+
+    Raises:
+        ValidTimeStampError: No valid timestamps found.
+
+    """
+    keymap = {
+        "Zh": "Zh",
+        "v": "v",
+        "width": "width",
+        "ldr": "ldr",
+        "kurt": "kurtosis",
+        "Skew": "skewness",
+        "SNR": "SNR",
+        "time": "time",
+        "range": "range",
+        "lwp": "lwp",
+        "SurfRelHum": "relative_humidity",
+        "rain": "rainfall_rate",
+        "Nyquist_velocity": "nyquist_velocity",
+        "range_offsets": "chirp_start_indices",
+    }
+
+    with Bowtie(bowtie_file, site_meta) as bowtie:
+        bowtie.init_data(keymap)
+        bowtie.add_time_and_range()
+        if date is not None:
+            bowtie.check_date(date)
+        bowtie.add_radar_specific_variables()
+        bowtie.add_site_geolocation()
+        bowtie.add_height()
+        bowtie.convert_units()
+        bowtie.test_if_all_masked()
+    attributes = output.add_time_attribute(ATTRIBUTES, bowtie.date)
+    output.update_attributes(bowtie.data, attributes)
+    return output.save_level1b(bowtie, output_file, uuid)
+
+
+class Bowtie(NcRadar):
+    def __init__(self, full_path: str | PathLike, site_meta: dict):
+        super().__init__(full_path, site_meta)
+        self.instrument = FMCW94
+        self.date = self.get_date()
+
+    def convert_units(self):
+        self.data["lwp"].data *= G_TO_KG
+        self.data["rainfall_rate"].data *= MM_H_TO_M_S
+        self.data["relative_humidity"].data /= 100
+
+    def check_date(self, date: str):
+        if "-".join(self.date) != date:
+            msg = f"Expected date {date} does not match the file date {self.date}"
+            raise ValueError(msg)
+
+
+ATTRIBUTES: dict = {
+    "v": MetaData(
+        long_name="Doppler velocity",
+        units="m s-1",
+        comment=(
+            "This parameter is the radial component of the velocity, with positive\n"
+            "velocities are away from the radar. It was corrected for the heave\n"
+            "motion of the ship. A rolling average over 3 time steps has been\n"
+            "applied to it."
+        ),
+    ),
+}

cloudnetpy/instruments/rpg.py

@@ -445,10 +445,6 @@ def _filter_zenith_angle(zenith: ma.MaskedArray) -> np.ndarray:
         long_name="Number of spectral samples in each chirp sequence",
         units="1",
     ),
-    "chirp_start_indices": MetaData(
-        long_name="Chirp sequences start indices",
-        units="1",
-    ),
     "number_of_averaged_chirps": MetaData(
         long_name="Number of averaged chirps in sequence",
         units="1",
@@ -517,10 +513,6 @@ def _filter_zenith_angle(zenith: ma.MaskedArray) -> np.ndarray:
         long_name="PC temperature",
         units="K",
     ),
-    "skewness": MetaData(
-        long_name="Skewness of spectra",
-        units="1",
-    ),
     "kurtosis": MetaData(
         long_name="Kurtosis of spectra",
         units="1",

cloudnetpy/metadata.py

@@ -93,6 +93,10 @@ class MetaData(NamedTuple):
         long_name="Kurtosis of spectra",
         units="1",
     ),
+    "skewness": MetaData(
+        long_name="Skewness of spectra",
+        units="1",
+    ),
     "nyquist_velocity": MetaData(long_name="Nyquist velocity", units="m s-1"),
     "radar_frequency": MetaData(long_name="Radar transmit frequency", units="GHz"),
     "beta": MetaData(
@@ -190,4 +194,8 @@ class MetaData(NamedTuple):
         units="dB",
         comment="SNR threshold used in data screening.",
     ),
+    "chirp_start_indices": MetaData(
+        long_name="Chirp sequences start indices",
+        units="1",
+    ),
 }

cloudnetpy/output.py

@@ -58,6 +58,9 @@ def _get_netcdf_dimensions(obj) -> dict:
     # RPG cloud radar
     if "chirp_start_indices" in obj.data:
         dimensions["chirp_sequence"] = len(obj.data["chirp_start_indices"][:])
+    # Bowtie
+    if "range_offsets" in obj.data:
+        dimensions["chirp_sequence"] = len(obj.data["range_offsets"][:])
     # disdrometer
     if hasattr(obj, "n_diameter") and hasattr(obj, "n_velocity"):
         dimensions["diameter"] = obj.n_diameter