Merge pull request #4 from hasimpson-usgs/StreamConverter

Stream converter

geomagio/ChannelConverter.py

@@ -83,7 +83,7 @@ def get_geo_x_from_mag(h, d):
     array_like
         x component
     """
-    return h * numpy.cos(d)
+    return numpy.multiply(h, numpy.cos(d))
 
 
 def get_geo_y_from_mag(h, d):
@@ -101,7 +101,7 @@ def get_geo_y_from_mag(h, d):
     array_like
         y component
     """
-    return h * numpy.sin(d)
+    return numpy.multiply(h, numpy.sin(d))
 
 
 # ###
@@ -168,7 +168,7 @@ def get_mag_d_from_obs(h, e, d0=0):
     array_like
         the total magnetic declination
     """
-    return d0 + get_obs_d_from_obs(h, e)
+    return numpy.add(d0, get_obs_d_from_obs(h, e))
 
 
 def get_mag_d_from_geo(x, y):
@@ -310,7 +310,7 @@ def get_obs_d_from_mag_d(d, d0=0):
     array_like
         the observatory d declination
     """
-    return d - d0
+    return numpy.subtract(d, d0)
 
 
 def get_obs_e_from_mag(h, d, d0=0):
@@ -331,7 +331,7 @@ def get_obs_e_from_mag(h, d, d0=0):
         the observatory e component
     """
     obs_d = get_obs_d_from_mag_d(d, d0)
-    return h * numpy.sin(obs_d)
+    return numpy.multiply(h, numpy.sin(obs_d))
 
 
 def get_obs_e_from_obs(h, d):
@@ -349,7 +349,7 @@ def get_obs_e_from_obs(h, d):
     array_like
         the observatory e component
     """
-    return h * numpy.tan(d)
+    return numpy.multiply(h, numpy.tan(d))
 
 
 def get_obs_h_from_mag(h, d, d0=0):
@@ -370,7 +370,7 @@ def get_obs_h_from_mag(h, d, d0=0):
         the observatory h component
     """
     obs_d = get_obs_d_from_mag_d(d, d0)
-    return h * numpy.cos(obs_d)
+    return numpy.multiply(h, numpy.cos(obs_d))
 
 
 def get_radians_from_minutes(m):
@@ -380,7 +380,7 @@ def get_radians_from_minutes(m):
     d: array_like
         the decimal value to be converted
     """
-    return m * M2R
+    return numpy.multiply(m, M2R)
 
 
 def get_minutes_from_radians(r):
@@ -391,4 +391,4 @@ def get_minutes_from_radians(r):
     r: float
         the radian value to be converted
     """
-    return r * R2M
+    return numpy.multiply(r, R2M)

geomagio/ChannelConverterTest.py

@@ -40,6 +40,10 @@ class ChannelConverterTest:
             geographic north.
         Y: the component corresponding to the field strength along
             geographic east.
+
+    We are using triangle identities for variables to test with.  Specifically
+        the hypotenuse is normally equal to 1, causing the adjacent angle
+        length to be cos(angle) and the opposite length to be sin(angle)
     """
 
     def test_get_geo_from_obs(self):

geomagio/StreamConverter.py

@@ -13,7 +13,29 @@ import ChannelConverter
 
 
 def get_geo_from_mag(mag):
-    pass
+    """Convert a stream to geographic coordinate system.
+
+    Parameters
+    ----------
+    stream : obspy.core.Stream
+        stream containing observatory components H, D, Z, and F.
+
+    Returns
+    -------
+    obspy.core.Stream
+        new stream object containing geographic components X, Y, Z, and F.
+    """
+    h = mag.select(channel='H')[0]
+    d = mag.select(channel='D')[0]
+    z = mag.select(channel='Z')[0]
+    f = mag.select(channel='F')[0]
+    mag_h = h.data
+    mag_d = d.data
+    (geo_x, geo_y) = ChannelConverter.get_geo_from_mag(mag_h, mag_d)
+    return obspy.core.Stream((
+        __get_trace('X', h.stats, geo_x),
+        __get_trace('Y', d.stats, geo_y),
+        z, f))
 
 
 def get_geo_from_obs(obs):
@@ -33,7 +55,29 @@ def get_geo_from_obs(obs):
 
 
 def get_mag_from_geo(geo):
-    pass
+    """Convert a stream to magnetic coordinate system.
+
+    Parameters
+    ----------
+    geo: obspy.core.Stream
+        stream containing observatory components X, Y, Z, and F.
+
+    Returns
+    -------
+    obspy.core.Stream
+        new stream object containing magnetic components H, D, Z, and F.
+    """
+    x = geo.select(channel='X')[0]
+    y = geo.select(channel='Y')[0]
+    z = geo.select(channel='Z')[0]
+    f = geo.select(channel='F')[0]
+    geo_x = x.data
+    geo_y = y.data
+    (mag_h, mag_d) = ChannelConverter.get_mag_from_geo(geo_x, geo_y)
+    return obspy.core.Stream((
+            __get_trace('H', x.stats, mag_h),
+            __get_trace('D', y.stats, mag_d),
+            z, f))
 
 
 def get_mag_from_obs(obs):
@@ -50,22 +94,22 @@ def get_mag_from_obs(obs):
         new stream object containing magnetic components H, D, Z, and F.
     """
     h = obs.select(channel='H')[0]
-    d = __get_obs_d_from_obs(obs)
+    e = __get_obs_e_from_obs(obs)
     z = obs.select(channel='Z')[0]
     f = obs.select(channel='F')[0]
     obs_h = h.data
-    obs_d = d.data
+    obs_e = e.data
     d0 = ChannelConverter.get_radians_from_minutes(
-            numpy.float64(d.stats['DECBAS']) / 10)
-    (mag_h, mag_d) = ChannelConverter.get_mag_from_obs(obs_h, obs_d, d0)
+            numpy.float64(e.stats['DECBAS']) / 10)
+    (mag_h, mag_d) = ChannelConverter.get_mag_from_obs(obs_h, obs_e, d0)
     return obspy.core.Stream((
             __get_trace('H', h.stats, mag_h),
-            __get_trace('D', d.stats, mag_d),
+            __get_trace('D', e.stats, mag_d),
             z, f))
 
 
-def get_obs_from_geo(geo, include_e=False):
-    """Convert a stream to geographic coordinate system.
+def get_obs_from_geo(geo, include_d=False):
+    """Convert a stream to observatory coordinate system.
 
     Parameters
     ----------
@@ -79,15 +123,72 @@ def get_obs_from_geo(geo, include_e=False):
     obspy.core.Stream
         new stream object containing observatory components H, D, E, Z, and F.
     """
-    return get_obs_from_mag(get_mag_from_geo(geo))
+    return get_obs_from_mag(get_mag_from_geo(geo), include_d)
+
+
+def get_obs_from_mag(mag, include_d=False):
+    """Convert a stream to magnetic observatory coordinate system.
+
+    Parameters
+    ----------
+    stream: obspy.core.Stream
+        stream containing magnetic components H, D, Z, and F.
+    include_e: boolean
+        whether to also include the observatory E component
+
+    Returns
+    -------
+    obspy.core.Stream
+        new stream object containing observatory components H, D, E, Z, and F
+    """
+    h = mag.select(channel='H')[0]
+    d = mag.select(channel='D')[0]
+    z = mag.select(channel='Z')[0]
+    f = mag.select(channel='F')[0]
+    mag_h = h.data
+    mag_d = d.data
+    d0 = ChannelConverter.get_radians_from_minutes(
+        numpy.float64(d.stats['DECBAS']) / 10)
+    (obs_h, obs_e) = ChannelConverter.get_obs_from_mag(mag_h, mag_d, d0)
 
+    traces = (
+        __get_trace('H', h.stats, obs_h),
+        __get_trace('E', d.stats, obs_e),
+        z, f)
+    if include_d:
+        obs_d = ChannelConverter.get_obs_d_from_obs(obs_h, obs_e)
+        traces = traces + (__get_trace('D', d.stats, obs_d),)
+    return obspy.core.Stream(traces)
 
-def get_obs_from_mag(mag, include_e=False):
-    # TODO
-    obs = obspy.core.Stream()
+
+def get_obs_from_obs(obs, include_e=False, include_d=False):
+    """Fill in the observatory parameters as requested
+
+    Parameters
+    ----------
+    stream: obspy.core.Stream
+        stream containing the observatory components H, D of E, Z, and F.
+    include_e: boolean
+        whether to include the e component
+    include_d: boolean
+        whether to include the d component
+
+    Returns
+    -------
+    obspy.core.Stream
+        new stream object containing observatory components H, D, E, Z, and F
+    """
+    h = obs.select(channel='H')[0]
+    z = obs.select(channel='Z')[0]
+    f = obs.select(channel='F')[0]
+    traces = (h, z, f)
+    if include_d:
+        d = __get_obs_d_from_obs(obs)
+        traces = traces + (d, )
     if include_e:
-        obs += __get_obs_e_from_obs(obs)
-    return obs
+        e = __get_obs_e_from_obs(obs)
+        traces = traces + (e, )
+    return obspy.core.Stream(traces)
 
 
 def __get_trace(channel, stats, data):

geomagio/StreamConverter_test.py

+"""Unit Tests for StreamConverter
+
+Notes
+-----
+
+We are using triangle identities for variables to test with.  Specifically
+    the hypotenuse is normally equal to 1, causing the adjacent angle length
+    to be cos(angle) and the opposite length to be sin(angle)
+
+For more info on the components see the Notes in ChannelConverterTest.py.
+"""
+import obspy.core
+import numpy
+import StreamConverter
+import ChannelConverter
+
+assert_equals = numpy.testing.assert_equal
+assert_almost_equals = numpy.testing.assert_almost_equal
+
+cos = numpy.cos
+sin = numpy.sin
+
+D2R = numpy.pi / 180
+D2I = 60 * 10               # Degrees to Iaga Decbas
+STARTTIME = obspy.core.UTCDateTime('2014-11-01')
+
+
+def test_get_geo_from_mag():
+    """geomag.StreamConverter_test.test_get_geo_from_mag()
+
+    The magnetic north stream containing the traces ''h'', ''d'', ''z'', and
+    ''f'' converts to the geographics stream containing the traces ''x'',
+    ''y'', ''z'' and ''f''
+    """
+    mag = obspy.core.Stream()
+
+    # Call get_geo_from_magusing a decbas of 15 degrees, and streams with
+    #   H = [1, 1], and D = [15 degrees, 30 degrees], expect streams of
+    #   X = [cos(15), cos(30)] and Y = [sin(15), sin(30)]
+    # stats.DECBAS = 15 * D2I
+    mag += __create_trace('H', [1, 1])
+    mag += __create_trace('D', [15 * D2R, 30 * D2R])
+    mag += __create_trace('Z', [1, 1])
+    mag += __create_trace('F', [1, 1])
+    geo = StreamConverter.get_geo_from_mag(mag)
+    X = geo.select(channel='X')[0].data
+    Y = geo.select(channel='Y')[0].data
+    assert_equals(X, [cos(15 * D2R), cos(30 * D2R)],
+        'Expect X to equal [cos(15), cos(30)]', True)
+    assert_equals(Y, [sin(15 * D2R), sin(30 * D2R)],
+        'Expect Y to equal [sin(15), sin(30)]', True)
+
+
+def test_get_geo_from_obs():
+    """geomag.StreamConverter_test.test_get_geo_from_obs()
+
+    The observatory stream containing the observatory traces
+    ''h'', ''d'' or ''e'', ''z'', and ''f'' converts to the geographic
+    stream containing the traces ''x'', ''y'', ''z'', and ''f''
+    """
+    obs = obspy.core.Stream()
+
+    # 1) Call get_geo_from_obs using equal h, e streams with a decbas of 0
+    #   the geographic stream values X, Y will be the same.
+    obs += __create_trace('H', [1])
+    obs += __create_trace('E', [1])
+    obs += __create_trace('Z', [1])
+    obs += __create_trace('F', [1])
+    geo = StreamConverter.get_geo_from_obs(obs)
+    X = geo.select(channel='X')[0].data
+    Y = geo.select(channel='Y')[0].data
+    assert_almost_equals(X[0], 1, 9,
+        'Expect X to almost equal 1', True)
+    assert_almost_equals(Y[0], 1, 9,
+        'Expect Y to almost equal 1', True)
+
+    # 2) Call get_geo_from_obs using a decbas of 15 degrees, and streams
+    #   with H = [cos(15), cos(30)], and E = [sin(15), sin(30)].
+    #   Expect streams of X = [cos(30), cos(45)] and Y = sin(30), sin(45)
+    obs = obspy.core.Stream()
+    DECBAS = 15 * D2I
+    obs += __create_trace('H', [cos(15 * D2R), cos(30 * D2R)], DECBAS)
+    obs += __create_trace('E', [sin(15 * D2R), sin(30 * D2R)], DECBAS)
+    obs += __create_trace('Z', [1, 1], DECBAS)
+    obs += __create_trace('F', [1, 1], DECBAS)
+    geo = StreamConverter.get_geo_from_obs(obs)
+    X = geo.select(channel='X')[0].data
+    Y = geo.select(channel='Y')[0].data
+    assert_equals(X, [cos(30 * D2R), cos(45 * D2R)],
+        'Expect X to equal [cos(30), cos(45)]', True)
+    assert_equals(Y, [sin(30 * D2R), sin(45 * D2R)],
+        'Expect Y to equal [sin(30), sin(45)]', True)
+
+
+def test_get_mag_from_geo():
+    """geomag.StreamConverter_test.test_get_mag_from_geo()
+
+    The geographic stream containing the traces ''x'', ''y'', ''z'', and
+        ''f'' converts to the magnetic stream containing the traces
+        ''h'', ''d'', ''z'' and ''f''.
+    """
+    geo = obspy.core.Stream()
+
+    # Call get_mag_from_geo using a decbas of 15, a X stream of
+    #   [cos(15), cos(30)], and a Y stream of [sin(15), sin(30)].
+    #   Expect a H stream of [1,1] and a D strem of [15 degrees, 30 degrees]
+    DECBAS = 15 * D2I
+    geo += __create_trace('X', [cos(15 * D2R), cos(30 * D2R)], DECBAS)
+    geo += __create_trace('Y', [sin(15 * D2R), sin(30 * D2R)], DECBAS)
+    geo += __create_trace('Z', [1, 1], DECBAS)
+    geo += __create_trace('F', [1, 1], DECBAS)
+    mag = StreamConverter.get_mag_from_geo(geo)
+    H = mag.select(channel='H')[0].data
+    D = mag.select(channel='D')[0].data
+    assert_equals(H, [1, 1],
+        'Expect H to equal [1,1]', True)
+    assert_equals(D, [15 * D2R, 30 * D2R],
+        'Expect D to equal [15 degrees, 30 degrees]', True)
+
+
+def test_get_mag_from_obs():
+    """geomag.StreamConverter_test.test_get_mag_from_obs()
+
+    The observatory stream containing the traces ''h'', ''e'' or ''d'',
+        ''z'' and ''f''
+    """
+    obs = obspy.core.Stream()
+
+    # Call get_mag_from_obs using a DECBAS of 15 degrees, a H stream of
+    #   [cos(15), cos(30)] and a E stream of [sin(15), sin(30)].
+    #   Expect a H stream of [1, 1] and a D stream of [30 degrees, 45 degrees]
+    DECBAS = 15 * D2I
+    obs += __create_trace('H', [cos(15 * D2R), cos(30 * D2R)], DECBAS)
+    obs += __create_trace('E', [sin(15 * D2R), sin(30 * D2R)], DECBAS)
+    obs += __create_trace('Z', [1, 1], DECBAS)
+    obs += __create_trace('F', [1, 1], DECBAS)
+    mag = StreamConverter.get_mag_from_obs(obs)
+    H = mag.select(channel='H')[0].data
+    D = mag.select(channel='D')[0].data
+    assert_equals(H, [1, 1],
+        'Expect H to equal [1,1]', True)
+    assert_equals(D, [30 * D2R, 45 * D2R],
+        'Expect D to equal [30 degrees, 45 degrees]', True)
+
+
+def test_get_obs_from_geo():
+    """geomag.StreamConverter_test.test_get_obs_from_geo()
+
+    The geographic stream containing the traces ''x'', ''y'', ''z'', and
+    ''f'' converts to the observatory stream containing the traces
+    ''h'', ''d'' or ''e'', ''z'', and ''f''.
+    """
+    geo = obspy.core.Stream()
+
+    # Call get_geo_from_obs using a decbas of 15, a X stream of
+    #   [cos(30), cos(45)], and a Y stream of [sin(30), sin(45)].
+    #   Expect a H stream of [cos(15), cos(30)] and a
+    #   E stream of [sin(15), sin(30)]
+    DECBAS = 15 * D2I
+    geo += __create_trace('X', [cos(30 * D2R), cos(45 * D2R)], DECBAS)
+    geo += __create_trace('Y', [sin(30 * D2R), sin(45 * D2R)], DECBAS)
+    geo += __create_trace('Z', [1, 1], DECBAS)
+    geo += __create_trace('F', [1, 1], DECBAS)
+    obs = StreamConverter.get_obs_from_geo(geo, True)
+    H = obs.select(channel='H')[0].data
+    E = obs.select(channel='E')[0].data
+    D = obs.select(channel='D')[0].data
+    assert_almost_equals(H, [cos(15 * D2R), cos(30 * D2R)], 9,
+        'Expect H to equal [cos(15), cos(30)]', True)
+    assert_almost_equals(E, [sin(15 * D2R), sin(30 * D2R)], 9,
+        'Expect E to equal [sin(15), sin(30)', True)
+    assert_almost_equals(D, [15 * D2R, 30 * D2R], 9,
+        'Expect D to equal [15 degress, 30 degrees]', True)
+
+
+def test_get_obs_from_mag():
+    """geomag.StreamConverter_test.test_get_obs_from_mag()
+
+    The magnetic stream containing the traces ''h'', ''d'', ''z'', and ''f''
+        converts to the observatory stream containing the traces
+        ''h'', ''e'' and/or ''d'', ''z'', and ''f''
+    """
+    mag = obspy.core.Stream()
+
+    # Call get_obs_from_mag using a decbas of 15, a H stream of [1,1],
+    #   and a D stream of [30 degrees, 45 degrees]. Expect a H stream
+    #   of [cos(15), cos(30)], a D stream of [30 degrees, 45 degrees],
+    #   and a E stream of [sin(15), sin(30)]
+    DECBAS = 15 * D2I
+    mag += __create_trace('H', [1, 1], DECBAS)
+    mag += __create_trace('D', [30 * D2R, 45 * D2R], DECBAS)
+    mag += __create_trace('Z', [1, 1], DECBAS)
+    mag += __create_trace('F', [1, 1], DECBAS)
+    obs = StreamConverter.get_obs_from_mag(mag, True)
+    H = obs.select(channel='H')[0].data
+    D = obs.select(channel='D')[0].data
+    E = obs.select(channel='E')[0].data
+    assert_almost_equals(H, [cos(15 * D2R), cos(30 * D2R)], 9,
+        'Expect H to equal [cos(15), cos(30)', True)
+    assert_almost_equals(D, [15 * D2R, 30 * D2R], 9,
+        'Expect D to equal [15 degrees, 30 degrees', True)
+    assert_almost_equals(E, [sin(15 * D2R), sin(30 * D2R)], 9,
+        'Expect E to equal [sin(15), sin(30)', True)
+
+
+def test_get_obs_from_obs():
+    """geomag.StreamConverter_test.test_get_obs_from_obs()
+
+    The observatory stream can contain either ''d'' or ''e'' depending
+    on it's source. get_obs_from_obs will return either or both as part
+    of the obs Stream.
+    """
+
+    # 1) Call get_obs_from_obs using a decbas of 15, a H stream of
+    #   [cos(15), cos(30)], and a E stream of [sin(15), sin(30)].
+    #   Expect a D stream of [15 degrees, 30 degrees]
+    obs_e = obspy.core.Stream()
+    DECBAS = 15 * D2I
+    obs_e += __create_trace('H', [cos(15 * D2R), cos(30 * D2R)], DECBAS)
+    obs_e += __create_trace('E', [sin(15 * D2R), sin(30 * D2R)], DECBAS)
+    obs_e += __create_trace('Z', [1, 1], DECBAS)
+    obs_e += __create_trace('F', [1, 1], DECBAS)
+    obs_D = StreamConverter.get_obs_from_obs(obs_e, False, True)
+    d = obs_D.select(channel='D')[0].data
+    assert_almost_equals(d, [15 * D2R, 30 * D2R], 9,
+        'Expect D to equal [15 degrees, 30 degrees]', True)
+
+    # 2) Call get_obs_from_obs using a decbase of 15 degrees, a H stream of
+    #   [cos(15), cos(30)], and a D stream of [15, 30].
+    #   Expect a D stream of [sin(15), sin(30)]
+    obs_d = obspy.core.Stream()
+    obs_d += __create_trace('H', [cos(15 * D2R), cos(30 * D2R)], DECBAS)
+    obs_d += __create_trace('D', [15 * D2R, 30 * D2R], DECBAS)
+    obs_d += __create_trace('Z', [1, 1], DECBAS)
+    obs_d += __create_trace('F', [1, 1], DECBAS)
+    obs_E = StreamConverter.get_obs_from_obs(obs_d, True, False)
+    e = obs_E.select(channel='E')[0].data
+    assert_almost_equals(e, [sin(15 * D2R), sin(30 * D2R)], 9,
+        'Expect E to equal [sin(15), sin(30)', True)
+
+
+def test_verification_data():
+    """
+    This is a verification test of data done with different
+    converters,  to see if the same result is returned.
+    Since the small angle approximation was used in the other
+    converters, AND round off was done differently,  we can't
+    get the exact results.
+    Change the precision in assert_almost_equals to larger precision
+    (ie 2 to 8) to see how off the data is. Most are well within
+    expectations.
+    """
+    DECBAS = 552.7
+    obs_v = obspy.core.Stream()
+    obs_v += __create_trace('H',
+        [20889.55, 20889.57, 20889.74, 20889.86, 20889.91, 20889.81], DECBAS)
+    obs_v += __create_trace('E',
+        [-21.10, -20.89, -20.72, -20.57, -20.39, -20.12], DECBAS)
+    obs_v += __create_trace('Z',
+        [47565.29, 47565.34, 47565.39, 47565.45, 47565.51, 47565.54], DECBAS)
+    obs_v += __create_trace('F',
+        [52485.77, 52485.84, 52485.94, 52486.06, 52486.11, 52486.10], DECBAS)
+    obs_V = StreamConverter.get_obs_from_obs(obs_v, True, True)
+    d = obs_V.select(channel='D')[0].data
+    d = ChannelConverter.get_minutes_from_radians(d)
+    # Using d values calculated using small angle approximation.
+    assert_almost_equals(d,
+        [-3.47, -3.43, -3.40, -3.38, -3.35, -3.31], 2,
+        'Expect d to equal [-3.47, -3.43, -3.40, -3.38, -3.35, -3.31]', True)
+
+    mag = obspy.core.Stream()
+    DECBAS = 552.7
+    mag += __create_trace('H',
+        [20884.04, 20883.45, 20883.38, 20883.43, 20883.07, 20882.76], DECBAS)
+    d = ChannelConverter.get_radians_from_minutes(
+        [556.51, 556.52, 556.56, 556.61, 556.65, 556.64])
+    mag += __create_trace('D', d, DECBAS)
+    mag += __create_trace('Z',
+        [48546.90, 48546.80, 48546.80, 48546.70, 48546.80, 48546.90], DECBAS)
+    mag += __create_trace('F',
+        [0.10, 0.00, 0.10, 0.00, 0.00, 0.00, 0.00], DECBAS)
+    geo = StreamConverter.get_geo_from_mag(mag)
+    X = geo.select(channel='X')[0].data
+    Y = geo.select(channel='Y')[0].data
+    assert_almost_equals(X,
+        [20611.00, 20610.40, 20610.30, 20610.30, 20609.90, 20609.60], 2)
+    assert_almost_equals(Y,
+        [3366.00, 3366.00, 3366.20, 3366.50, 3366.70, 3366.60], 1)
+
+
+def __create_trace(channel, data, decbase=0):
+    """
+    Utility to create a trace containing the given numpy array.
+
+    Parameters
+    ----------
+    channel: string
+        The name of the trace being created.
+    data: array
+        The array to be inserted into the trace.
+
+    Returns
+    -------
+    obspy.core.Stream
+        Stream containing the channel.
+    """
+    stats = obspy.core.Stats()
+    stats.starttime = STARTTIME
+    stats.sampling_rate = 0.0166666666667
+    stats.DECBAS = decbase
+    stats.channel = channel
+    numpy_data = numpy.array(data, dtype=numpy.float64)
+    return obspy.core.Trace(numpy_data, stats)

geomagio/iaga2002/IAGA2002Factory.py

@@ -6,6 +6,7 @@ import os
 from geomagio import TimeseriesFactory, TimeseriesFactoryException
 from IAGA2002Parser import IAGA2002Parser
 from IAGA2002Writer import IAGA2002Writer
+from geomagio import ChannelConverter
 
 
 # pattern for iaga 2002 file names
@@ -103,14 +104,15 @@ class IAGA2002Factory(TimeseriesFactory):
         timeseries = obspy.core.Stream()
         for day in days:
             url = self._get_url(observatory, day, type, interval)
-            timeseries += self._parse_url(url)
+            iagaFile = read_url(url)
+            timeseries += self.parse_file(iagaFile)
         # merge channel traces for multiple days
         timeseries.merge()
         # trim to requested start/end time
         timeseries.trim(starttime, endtime)
         return timeseries
 
-    def _parse_url(self, url):
+    def parse_file(self, iagaFile):
         """Parse the contents of a url to an IAGA2002 file.
 
         Parameters
@@ -124,7 +126,7 @@ class IAGA2002Factory(TimeseriesFactory):
             parsed data.
         """
         parser = IAGA2002Parser()
-        parser.parse(read_url(url))
+        parser.parse(iagaFile)
         headers = parser.headers
         station = headers['IAGA CODE']
         comments = tuple(parser.comments)
@@ -143,6 +145,9 @@ class IAGA2002Factory(TimeseriesFactory):
             stats.network = 'IAGA'
             stats.station = station
             stats.channel = channel
+            if stats.channel == 'D':
+                data[channel] = ChannelConverter.get_radians_from_minutes(
+                    data[channel])
             stream += obspy.core.Trace(data[channel], stats)
         return stream
 

geomagio/iaga2002/IAGA2002Writer.py

 
 from cStringIO import StringIO
-from geomagio import TimeseriesFactoryException
+from geomagio import TimeseriesFactoryException, ChannelConverter
 import numpy
 import IAGA2002Parser
 import textwrap
@@ -105,6 +105,9 @@ class IAGA2002Writer(object):
             list and order of channel values to output.
         """
         buf = []
+        if timeseries.select(channel='D'):
+            d = timeseries.select(channel='D')
+            d[0].data = ChannelConverter.get_minutes_from_radians(d[0].data)
         traces = [timeseries.select(channel=c)[0] for c in channels]
         starttime = float(traces[0].stats.starttime)
         delta = traces[0].stats.delta