--- a/atmospheric_lidar/raymetrics.py Tue Feb 27 18:41:06 2018 +0200
+++ b/atmospheric_lidar/raymetrics.py Wed Feb 28 12:04:10 2018 +0200
@@ -1,25 +1,81 @@
""" Code to read Raymetrics version of Licel binary files."""
-import datetime
import logging
-import numpy as np
-import pytz
-
from .licel import LicelFile, LicelLidarMeasurement, LicelChannel, PhotodiodeChannel
logger = logging.getLogger(__name__)
class ScanningFile(LicelFile):
+ """ Raymetrics is using a custom version of licel file format to store scanning lidar measurements.
+
+ The file includes one extra line describing the scan strategy of the dataset. The extra parameters are:
+
+ `azimuth_start`
+ Start azimuth angle for the scan, relative to instrument zero position (degrees).
+
+ `azimuth_stop`
+ Stop azimuth angle for the scan, relative to instrument zero position (degrees).
+
+ `azimuth_step`
+ Step of the azimuth scan (degrees).
+
+ `zenith_start`
+ Start zenith angle for the scan, relative to *nadir* (degrees). Take care that this is actually
+ nadir angle. Vertical measurements correspond to -90.
+
+ `zenith_stop`
+ Stop zenith angle for the scan, relative to *nadir* (degrees). Take care that this is actually
+ nadir angle. Vertical measurements correspond to -90.
+
+ `zenith_step`
+ Step of the zenith scan (degrees).
+
+ `azimuth_offset`
+ Offset of instrument zero from North (degrees). Using this value you can convert `azimuth_start` and
+ `azimuth_stop` to absolute values.
+
+ Moreover, four new parameters are added in the second line of the file:
+
+ `zenith_angle`
+ Zenith angle of the current file. Take care that this is actually
+ nadir angle. Vertical measurements correspond to -90.
+
+ `azimuth_angle`
+ Azimuth angle of the current file. Value relative to instrument zero position.
+
+ `temperature`
+ Ambient temperature (degrees C)
+
+ `pressure`
+ Ambient pressure (hPa)
+ """
+
+ # Specifications of the header lines.
licel_file_header_format = ['filename',
'start_date start_time end_date end_time altitude longitude latitude zenith_angle azimuth_angle temperature pressure',
# Appart from Site that is read manually
- 'azimuth_start azimuth_stop azimuth_step zenith_start zenith_finish zenith_step azimuth_offset',
+ 'azimuth_start azimuth_stop azimuth_step zenith_start zenith_stop zenith_step azimuth_offset',
'LS1 rate_1 LS2 rate_2 number_of_datasets', ]
+
+ # Specifications of the channel lines in the header
licel_file_channel_format = 'active analog_photon laser_used number_of_datapoints 1 HV bin_width wavelength d1 d2 d3 d4 ADCbits number_of_shots discriminator ID'
def _read_rest_of_header(self, f):
- """ Read the rest of the header lines, after line 2. """
+ """ Read the third and fourth row of of the header lines.
+
+ The first two rows are read in the licel class.
+
+ Parameters
+ ----------
+ f : file
+ An open file-like object.
+
+ Returns
+ -------
+ raw_info : dict
+ A dictionary containing all parameters of the third and fourth line of the header.
+ """
raw_info = {}
third_line = f.readline()
@@ -30,6 +86,7 @@
return raw_info
def _assign_properties(self):
+ """ Assign scanning-specific parameters found in the header as object properties."""
super(ScanningFile, self)._assign_properties()
self.azimuth_angle = float(self.raw_info['altitude'])
self.temperature = float(self.raw_info['temperature'])
@@ -38,12 +95,14 @@
self.azimuth_stop = float(self.raw_info['azimuth_stop'])
self.azimuth_step = float(self.raw_info['azimuth_step'])
self.zenith_start = float(self.raw_info['zenith_start'])
- self.zenith_finish = float(self.raw_info['zenith_finish'])
+ self.zenith_stop = float(self.raw_info['zenith_stop'])
self.zenith_step = float(self.raw_info['zenith_step'])
self.azimuth_offset = float(self.raw_info['azimuth_offset'])
class ScanningChannel(LicelChannel):
+ """ A class representing measurements of a specific lidar channel, during a scanning measurement. """
+
def __init__(self):
super(ScanningChannel, self).__init__()
@@ -51,28 +110,43 @@
self.azimuth_stop = None
self.azimuth_step = None
self.zenith_start = None
- self.zenith_finish = None
+ self.zenith_stop = None
self.zenith_step = None
self.azimuth_offset = None
self.zenith_angles = []
self.azimuth_angles = []
def append_file(self, current_file, file_channel):
+ """ Keep track of scanning-specific variable properties of each file. """
super(ScanningChannel, self).append_file(current_file, file_channel)
self.zenith_angles.append(current_file.zenith_angle)
self.azimuth_angles.append(current_file.azimuth_angle)
def _assign_properties(self, current_file, file_channel):
+ """ Assign scanning-specific properties as object properties. Check that these are unique,
+ i.e. that all files belong to the same measurements set.
+
+ Parameters
+ ----------
+ current_file : ScanningFile object
+ A ScanningFile object being imported
+ file_channel : LicelChannelData object
+ A specific LicelChannelData object holding data found in the file.
+ """
super(ScanningChannel, self)._assign_properties(current_file, file_channel)
self._assign_unique_property('azimuth_start', current_file.azimuth_start)
self._assign_unique_property('azimuth_stop', current_file.azimuth_stop)
self._assign_unique_property('azimuth_step', current_file.azimuth_step)
self._assign_unique_property('zenith_start', current_file.zenith_start)
- self._assign_unique_property('zenith_finish', current_file.zenith_finish)
+ self._assign_unique_property('zenith_stop', current_file.zenith_stop)
self._assign_unique_property('zenith_step', current_file.zenith_step)
class ScanningLidarMeasurement(LicelLidarMeasurement):
+ """ A class representing a scanning measurement set.
+
+ It useses `ScanningFile` and `ScanningChannel` classes for handling the data.
+ """
file_class = ScanningFile
channel_class = ScanningChannel
photodiode_class = PhotodiodeChannel
