Added a configuration parser, and converted dsd moments and radar mom…

…ents to use the new meta data fields (josephhardinee#38)

description.txt

@@ -1,3 +1,3 @@
 PyDisdrometer is a Python package to process disdrometer files. It currently is capable of reading several different types of disdrometers and calculating both important moment parameters, as well as radar derived parameters. It currently supports OTT Parsivel disdrometers and Joss Waldvogel Disdrometers. It is currently in alpha so functionality is limited but being expanded quickly.
 
-Author: Joseph C. Hardin
+Author: Joseph C. Hardin, Nick Guy

pydisdrometer/DropSizeDistribution.py

@@ -19,7 +19,7 @@
 
 from . import DSR
 from .utility import dielectric
-
+from .utility import configuration
 SPEED_OF_LIGHT=299792458
 
 class DropSizeDistribution(object):
@@ -57,51 +57,30 @@ class DropSizeDistribution(object):
 
     '''
 
-    def __init__(self, reader, time_start = None, location=None,):
+    def __init__(self, reader, time_start = None, location=None):
         '''Initializer for the DropSizeDistribution class.
 
         The DropSizeDistribution class holds dsd's returned from the various
         readers in the io module.
 
         Parameters
         ----------
-#         time: array_like
-#             An array of times corresponding to the time each dsd was sampled in minutes relative to time_start.
-#         Nd : 2d Array
-#             A list of drop size distributions
-#         spread: array_like
-#             Array giving the bin spread size for each size bin of the
-#             disdrometer.
-#         velocity: optional, array_like
-#             Terminal Fall Velocity for each size bin. This is based on the
-#             disdrometer assumptions.
-#         Z: optional, array_like
-#             The equivalent reflectivity factory from the disdrometer. Often
-#             taken as D**6.
-#         num_particles: optional, array_like
-#             Number of measured particles for each time instant.
-#         bin_edges: optional, array_like
-#             N+1 sized array of the boundaries of each size bin. For 30 bins
-#             for instance, there will be 31 different bin boundaries.
-#         diameter: optional, array_like
-#             The center size for each dsd bin.
-
         reader: object
             Object returned by package readers.
         time_start: datetime
             Recording Start time.
         location: tuple
             (Latitude, Longitude) pair in decimal format.
-        scattering_temp: optional, string
-            Scattering temperature string. One of ("0C","10C","20C").
-            Defaults to "10C"
 
         Returns
         -------
         dsd: `DropSizeDistribution` instance
             Drop Size Distribution instance.
 
         '''
+
+        self.config = configuration.Configuration() 
+
         self.time = reader.time
         self.Nd = reader.fields['Nd']
         self.spread = reader.spread
@@ -210,16 +189,15 @@ def calculate_radar_parameters(self, dsr_func = DSR.bc, scatter_time_range = Non
         for t in range(self.scatter_start_time, self.scatter_end_time):
             self.fields['Kdp']['data'][t] = radar.Kdp(self.scatterer)
             self.fields['Ai']['data'][t] = radar.Ai(self.scatterer)
-            self.fields['Ad']['data'][t] = radar.Ai(self.scatterer) -radar.Ai(self.scatterer, h_pol=False)
+            self.fields['Adr']['data'][t] = radar.Ai(self.scatterer) -radar.Ai(self.scatterer, h_pol=False)
 
-    def _setup_empty_fields(self, ):
+    def _setup_empty_fields(self ):
         ''' Preallocate arrays of zeros for the radar moments
         '''
-        self.fields['Zh'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['Zdr'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['Kdp'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['Ai'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['Ad'] = {'data': np.ma.zeros(self.numt)}
+        params_list = ['Zh', 'Zdr', 'Kdp', 'Ai', 'Adr']
+
+        for param in params_list:
+            self.fields[param] = self.config.fill_in_metadata(param, np.ma.zeros(self.numt))
 
     def _setup_scattering(self, wavelength, dsr_func):
         ''' Internal Function to create scattering tables.
@@ -292,15 +270,10 @@ def calculate_dsd_parameterization(self, method='bringi'):
 
         '''
 
-        self.fields['Nt'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['W'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['D0'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['Nw'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['Dmax'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['Dm'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['Nw'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['N0'] = {'data': np.ma.zeros(self.numt)}
-        self.fields['mu'] = {'data': np.ma.zeros(self.numt)}
+        params_list = ['D0', 'Dmax', 'Dm', 'Nt', 'Nw', 'N0', 'W', 'mu']
+
+        for param in params_list:
+            self.fields[param] = self.config.fill_in_metadata(param, np.ma.zeros(self.numt))
 
         rho_w = 1e-03  # grams per mm cubed Density of Water
         vol_constant = np.pi / 6.0 * rho_w

pydisdrometer/tests/testConfiguration.py

@@ -0,0 +1,17 @@
+# -*- coding: utf-8 -*-
+
+import numpy as np
+import unittest
+from ..utility import configuration
+
+from .. import DropSizeDistribution
+
+class testConfiguration(unittest.TestCase):
+    ''' Unit tests for Configuration Class'''
+
+    def setUp(self):
+        self.config = configuration.Configuration()
+
+    def test_config_loads_and_has_keys(self):
+        self.assertIsNotNone(self.config)
+        self.assertTrue(len(self.config.metadata.keys()) > 0 )

pydisdrometer/utility/configuration.py

@@ -0,0 +1,32 @@
+import json
+from copy import copy
+import os
+
+
+
+class Configuration(object):
+    ''' Class to store PyDisdrometer configuration options
+
+    Attributes:
+    -----------
+
+    '''
+    config_dir = os.path.dirname(os.path.abspath(__file__))
+    metadata_config_file = os.path.join(config_dir, 'metadata.json')
+
+    def __init__(self):
+        self.metadata = self.load_metadata_config()
+
+    def load_metadata_config(self):
+        ''' Load the metadata configuration file and return the dictionary'''
+        return json.load(open(self.metadata_config_file))
+
+
+    def fill_in_metadata(self, field, data):
+        metadata = self.metadata[field].copy()
+        metadata['data'] = copy(data)
+        return metadata
+
+
+
+

pydisdrometer/utility/metadata.json

@@ -0,0 +1,88 @@
+{
+    "D0":
+    {
+        "standard_name": "median_drop_diameter",
+        "units": "mm",
+        "long_name": "Median Drop Diameter"
+    },
+    "Dmax":
+    {
+        "standard_name": "maximum_drop_diameter",
+        "units": "mm",
+        "long_name" :"Maximum Drop Diameter"
+    },
+    "Dm":
+    {
+        "standard_name": "mean_drop_diameter",
+        "units": "mm",
+        "long_name" :"Mean Drop Diameter"
+    },
+    "Nw":
+    {
+        "standard_name": "normalized_intercept_parameter",
+        "units": "?",
+        "long_name" :"Normalized Intercept Parameter of a Normalized Gaussian Distribution"
+    },
+    "Nt":
+    {
+        "standard_name": "total_droplet_concentration",
+        "units": "m^-1",
+        "long_name" :"Total Droplet Concentration"
+    },
+    "N0":
+    {
+        "standard_name": "intercept_parameter",
+        "units": "?",
+        "long_name" :"Intercept Parameter of Modeled Drop Size Distribution"
+    },
+    "W":
+    {
+        "standard_name": "water_mass",
+        "units": "g/m^3",
+        "long_name" :"Water Mass of Drop Size Distribution"
+    },
+    "mu":
+    {
+        "standard_name": "shape_parameter",
+        "units": " ",
+        "long_name" :"Shape Parameter of Modeled Drop Size Distribution"
+    },
+    "rain_rate":
+    {
+        "standard_name": "rain_rate",
+        "units": "mm/h",
+        "long_name" :"Instantaneous Rainfall Rate of Water Flux"
+    },
+    "Zh":
+    {
+        "standard_name": "horizontal_reflectivity",
+        "units": "dBZ",
+        "long_name" :"Estimated Horizontal Radar Reflectivity from Drop Size Distribution"
+    },
+    "Zdr":
+    {
+        "standard_name": "differential_reflectivity",
+        "units": "dBZ",
+        "long_name" :"Estimated Differential Radar Reflectivity (H, V) from Drop Size Distribution"
+    },
+    "Kdp":
+    {
+        "standard_name": "specific_differential_phase",
+        "units": "deg",
+        "long_name" :"Specific Differential Phase from Drop Size Distribution"
+    },
+    "Ai":
+    {
+        "standard_name": "specific_attenuation",
+        "units": "dB/km",
+        "long_name": "Specific Attenuation"
+    },
+    "Adr":
+    {
+        "standard_name": "specific_differential_attenuation",
+        "units": "dB/km",
+        "long_name": "Specific Differential Attenuation"
+    }
+}
+
+