test_waveform.py

# -*- coding: utf-8 -*-
"""
The obspy.imaging.waveform test suite.
"""
from __future__ import (absolute_import, division, print_function,
                        unicode_literals)
from future.builtins import *  # NOQA

import os
import unittest

import numpy as np

from obspy import Stream, Trace, UTCDateTime
from obspy.core.event import read_events
from obspy.core.stream import read
from obspy.core.util import AttribDict
from obspy.core.util.testing import ImageComparison


class WaveformTestCase(unittest.TestCase):
    """
    Test cases for waveform plotting.
    """
    def setUp(self):
        # directory where the test files are located
        self.path = os.path.join(os.path.dirname(__file__), 'images')

    def _create_stream(self, starttime, endtime, sampling_rate):
        """
        Helper method to create a Stream object that can be used for testing
        waveform plotting.

        Takes the time frame of the Stream to be created and a sampling rate.
        Any other header information will have to be adjusted on a case by case
        basis. Please remember to use the same sampling rate for one Trace as
        merging and plotting will not work otherwise.

        This method will create a single sine curve to a first approximation
        with superimposed 10 smaller sine curves on it.

        :return: Stream object
        """
        time_delta = endtime - starttime
        number_of_samples = int(time_delta * sampling_rate) + 1
        # Calculate first sine wave.
        curve = np.linspace(0, 2 * np.pi, number_of_samples // 2)
        # Superimpose it with a smaller but shorter wavelength sine wave.
        curve = np.sin(curve) + 0.2 * np.sin(10 * curve)
        # To get a thick curve alternate between two curves.
        data = np.empty(number_of_samples)
        # Check if even number and adjust if necessary.
        if number_of_samples % 2 == 0:
            data[0::2] = curve
            data[1::2] = curve + 0.2
        else:
            data[-1] = 0.0
            data[0:-1][0::2] = curve
            data[0:-1][1::2] = curve + 0.2
        tr = Trace()
        tr.stats.starttime = starttime
        tr.stats.sampling_rate = float(sampling_rate)
        # Fill dummy header.
        tr.stats.network = 'BW'
        tr.stats.station = 'OBSPY'
        tr.stats.channel = 'TEST'
        tr.data = data
        return Stream(traces=[tr])

    def test_data_remains_unchanged(self):
        """
        Data should not be changed when plotting.
        """
        # Use once with straight plotting with random calibration factor
        st = self._create_stream(UTCDateTime(0), UTCDateTime(1000), 1)
        st[0].stats.calib = 0.2343
        org_st = st.copy()
        st.plot(format='png')
        self.assertEqual(st, org_st)
        # Now with min-max list creation (more than 400000 samples).
        st = self._create_stream(UTCDateTime(0), UTCDateTime(600000), 1)
        st[0].stats.calib = 0.2343
        org_st = st.copy()
        st.plot(format='png')
        self.assertEqual(st, org_st)
        # Now only plot a certain time frame.
        st.plot(
            format='png', starrtime=UTCDateTime(10000),
            endtime=UTCDateTime(20000))
        self.assertEqual(st, org_st)

    def test_plot_empty_stream(self):
        """
        Plotting of an empty stream should raise a warning.
        """
        st = Stream()
        self.assertRaises(IndexError, st.plot)

    def test_plot_same_trace_different_sample_rates(self):
        """
        Plotting of a Stream object, that contains two traces with the same id
        and different sampling rates should raise an exception.
        """
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 10, 1.0)
        st += self._create_stream(start + 10, start + 20, 10.0)
        self.assertRaises(Exception, st.plot)

    def test_plot_one_hour_many_samples(self):
        """
        Plots one hour, starting Jan 1970.

        Uses a frequency of 1000 Hz to get a sample count of over 3 Million and
        get in the range, that plotting will choose to use a minimum maximum
        approach to plot the data.
        """
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 3600, 1000.0)
        # create and compare image
        image_name = 'waveform_one_hour_many_samples.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name)

    def test_plot_one_hour_few_samples(self):
        """
        Plots one hour, starting Jan 1970.

        Uses a frequency of 10 Hz.
        """
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 3600, 10.0)
        # create and compare image
        image_name = 'waveform_one_hour_few_samples.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name)

    def test_plot_simple_gap_many_samples(self):
        """
        Plots three hours with a gap.

        There are 45 minutes of data at the beginning and 45 minutes of data at
        the end.
        """
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 3600 * 3 / 4, 500.0)
        st += self._create_stream(start + 2.25 * 3600, start + 3 * 3600, 500.0)
        # create and compare image
        image_name = 'waveform_simple_gap_many_samples.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name)

    def test_plot_simple_gap_few_samples(self):
        """
        Plots three hours with a gap.

        There are 45 minutes of data at the beginning and 45 minutes of data at
        the end.
        """
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 3600 * 3 / 4, 5.0)
        st += self._create_stream(start + 2.25 * 3600, start + 3 * 3600, 5.0)
        # create and compare image
        image_name = 'waveform_simple_gap_few_samples.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name)

    def test_plot_complex_gap_many_samples(self):
        """
        Plots three hours with a gap.

        There are 45 minutes of data at the beginning and 45 minutes of data at
        the end.
        """
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 3600 * 3 / 4, 500.0)
        st += self._create_stream(start + 2.25 * 3600, start + 3 * 3600, 500.0)
        st[0].stats.location = '01'
        st[1].stats.location = '01'
        temp_st = self._create_stream(start + 3600 * 3 / 4,
                                      start + 2.25 * 3600, 500.0)
        temp_st[0].stats.location = '02'
        st += temp_st
        # create and compare image
        image_name = 'waveform_complex_gap_many_samples.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name)

    def test_plot_complex_gap_few_samples(self):
        """
        Plots three hours with a gap.

        There are 45 minutes of data at the beginning and 45 minutes of data at
        the end.
        """
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 3600 * 3 / 4, 5.0)
        st += self._create_stream(start + 2.25 * 3600, start + 3 * 3600, 5.0)
        st[0].stats.location = '01'
        st[1].stats.location = '01'
        temp_st = self._create_stream(start + 3600 * 3 / 4,
                                      start + 2.25 * 3600, 5.0)
        temp_st[0].stats.location = '02'
        st += temp_st
        # create and compare image
        image_name = 'waveform_complex_gap_few_samples.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name)

    def test_plot_multiple_traces(self):
        """
        Plots multiple traces underneath.
        """
        # 1 trace
        st = read()[1]
        with ImageComparison(self.path, 'waveform_1_trace.png') as ic:
            st.plot(outfile=ic.name, automerge=False)
        # 3 traces
        st = read()
        with ImageComparison(self.path, 'waveform_3_traces.png') as ic:
            st.plot(outfile=ic.name, automerge=False)
        # 5 traces
        st = st[1] * 5
        with ImageComparison(self.path, 'waveform_5_traces.png') as ic:
            st.plot(outfile=ic.name, automerge=False)
        # 10 traces
        st = st[1] * 10
        with ImageComparison(self.path, 'waveform_10_traces.png') as ic:
            st.plot(outfile=ic.name, automerge=False)
        # 10 traces - huge numbers
        st = st[1] * 10
        for i, tr in enumerate(st):
            # scale data to have huge numbers
            st[i].data = tr.data * 10 ** i
        with ImageComparison(self.path, 'waveform_10_traces_huge.png') as ic:
            st.plot(outfile=ic.name, automerge=False, equal_scale=False)
        # 10 traces - tiny numbers
        st = st[1] * 10
        for i, tr in enumerate(st):
            # scale data to have huge numbers
            st[i].data = tr.data / (10 ** i)
        with ImageComparison(self.path, 'waveform_10_traces_tiny.png') as ic:
            st.plot(outfile=ic.name, automerge=False, equal_scale=False)

    def test_plot_with_labels(self):
        """
        Plots with labels.
        """
        st = read()
        st.label = u"Title #1 üöä?"
        st[0].label = 'Hello World!'
        st[1].label = u'Hällö Wörld & Marß'
        st[2].label = '*' * 80
        # create and compare image
        with ImageComparison(self.path, 'waveform_labels.png') as ic:
            st.plot(outfile=ic.name)

    def test_plot_binning_error(self):
        """
        Tests the plotting of a trace with a certain amount of sampling that
        had a binning problem.
        """
        tr = Trace(data=np.sin(np.linspace(0, 200, 432000)))
        # create and compare image
        with ImageComparison(self.path, 'waveform_binning_error.png') as ic:
            tr.plot(outfile=ic.name)

        tr = Trace(data=np.sin(np.linspace(0, 200, 431979)))
        # create and compare image
        with ImageComparison(self.path, 'waveform_binning_error_2.png') as ic:
            tr.plot(outfile=ic.name)

    def test_plot_default_section(self):
        """
        Tests plotting 10 traces in a horizontal section.
        """
        start = UTCDateTime(0)
        st = Stream()
        for _i in range(10):
            this_start = start + 300 * np.sin(np.pi * _i / 9)
            st += self._create_stream(this_start, this_start + 3600, 100)
            st[-1].stats.distance = _i * 10e3
        # create and compare image
        with ImageComparison(self.path, 'waveform_default_section.png') as ic:
            st.plot(outfile=ic.name, type='section')

    def test_plot_azim_section(self):
        """
        Tests plotting 10 traces in a azimuthal distant section.
        """
        start = UTCDateTime(0)
        st = Stream()
        for _i in range(10):
            st += self._create_stream(start, start + 3600, 100)
            st[-1].stats.coordinates = AttribDict({
                'latitude': _i,
                'longitude': _i})
        # create and compare image
        with ImageComparison(self.path, 'waveform_azim_section.png') as ic:
            st.plot(outfile=ic.name, type='section', dist_degree=True,
                    ev_coord=(0.0, 0.0))

    def test_plot_horizontal_section(self):
        """
        Tests plotting 10 traces in a horizontal section.
        """
        start = UTCDateTime(0)
        st = Stream()
        for _i in range(10):
            st += self._create_stream(start, start + 3600, 100)
            st[-1].stats.distance = _i * 10e3
        # create and compare image
        with ImageComparison(self.path, 'waveform_horiz_section.png') as ic:
            st.plot(outfile=ic.name, type='section', orientation='horizontal')

    def test_plot_ref_time_section(self):
        """
        Tests plotting 10 traces in a section with alternate reference time.
        """
        start = UTCDateTime(0)
        reftime = start + 600
        st = Stream()
        for _i in range(10):
            this_start = start + 300 * np.sin(np.pi * _i / 9)
            st += self._create_stream(this_start, this_start + 3600, 100)
            st[-1].stats.distance = _i * 10e3
        # create and compare image
        with ImageComparison(self.path, 'waveform_reftime_section.png') as ic:
            st.plot(outfile=ic.name, type='section', reftime=reftime)

    def test_plot_colored_section(self):
        """
        Tests plotting 10 traces in a section colored by channel.
        """
        start = UTCDateTime(0)
        st = Stream()
        for _i in range(10):
            this_start = start + 300 * np.sin(np.pi * _i / 9)
            st += self._create_stream(this_start, this_start + 3600, 100)
            st[-1].stats.distance = _i * 10e3
            st[-1].stats.channel = str(_i % 3)
        # create and compare image
        with ImageComparison(self.path, 'waveform_color_section.png') as ic:
            st.plot(outfile=ic.name, type='section', color='channel')

    def test_plot_default_relative(self):
        """
        Plots one hour, starting Jan 1970, with a relative scale.
        """
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 3600, 100)
        # create and compare image
        image_name = 'waveform_default_relative.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name, type='relative')

    def test_plot_ref_time_relative(self):
        """
        Plots one hour, starting Jan 1970, with a relative scale.

        The reference time is at 300 seconds after the start.
        """
        start = UTCDateTime(0)
        ref = UTCDateTime(300)
        st = self._create_stream(start, start + 3600, 100)
        # create and compare image
        image_name = 'waveform_reftime_relative.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name, type='relative', reftime=ref)

    def test_plot_day_plot(self):
        '''
        Plots day plot, starting Jan 1970.
        '''
        start = UTCDateTime(0)
        st = self._create_stream(start, start + 3 * 3600, 100)
        # create and compare image
        image_name = 'waveform_dayplot.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name, type='dayplot',
                    timezone='EST', time_offset=-5)

    def test_plot_day_plot_explicit_event(self):
        '''
        Plots day plot, starting Jan 1970, with several events.
        '''
        start = UTCDateTime(0)
        event1 = UTCDateTime(30)       # Event: Top left; Note: below right
        event2 = UTCDateTime(14 * 60)  # Event: Top right; Note: below left
        event3 = UTCDateTime(46 * 60)  # Event: Bottom left; Note: above right
        event4 = UTCDateTime(59 * 60)  # Event: Bottom right; Note: above left
        event5 = UTCDateTime(61 * 60)  # Should be ignored
        st = self._create_stream(start, start + 3600, 100)
        # create and compare image
        image_name = 'waveform_dayplot_event.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name, type='dayplot',
                    timezone='EST', time_offset=-5,
                    events=[{'time': event1, 'text': 'Event 1'},
                            {'time': event2, 'text': 'Event 2'},
                            {'time': event3, 'text': 'Event 3'},
                            {'time': event4, 'text': 'Event 4'},
                            {'time': event5, 'text': 'Event 5'}])

    def test_plot_day_plot_catalog(self):
        '''
        Plots day plot, with a catalog of events.
        '''
        start = UTCDateTime(2012, 4, 4, 14, 0, 0)
        cat = read_events()
        st = self._create_stream(start, start + 3600, 100)
        # create and compare image
        image_name = 'waveform_dayplot_catalog.png'
        with ImageComparison(self.path, image_name) as ic:
            st.plot(outfile=ic.name, type='dayplot',
                    timezone='EST', time_offset=-5,
                    events=cat)


def suite():
    return unittest.makeSuite(WaveformTestCase, 'test')

if __name__ == '__main__':
    unittest.main(defaultTest='suite')