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@@ 757-801 (lines=45) @@
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return alat, alon |
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def mlon2mlt(self, mlon, dtime, ssheight=318550): |
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"""Computes the magnetic local time at the specified magnetic longitude |
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and UT. |
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Parameters |
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---------- |
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mlon : array_like |
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Magnetic longitude (apex and quasi-dipole longitude are always |
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equal) |
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dtime : :class:`datetime.datetime` |
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Date and time |
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ssheight : float, optional |
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Altitude in km to use for converting the subsolar point from |
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geographic to magnetic coordinates. A high altitude is used |
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to ensure the subsolar point is mapped to high latitudes, which |
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prevents the South-Atlantic Anomaly (SAA) from influencing the MLT. |
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The current default is 50 * 6371, roughly 50 RE. (default=318550) |
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Returns |
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------- |
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mlt : ndarray or float |
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Magnetic local time in hours [0, 24) |
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Notes |
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----- |
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To compute the MLT, we find the apex longitude of the subsolar point at |
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the given time. Then the MLT of the given point will be computed from |
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the separation in magnetic longitude from this point (1 hour = 15 |
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degrees). |
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""" |
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# Get the subsolar location |
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ssglat, ssglon = helpers.subsol(dtime) |
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# Convert the subsolar location to apex coordinates |
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_, ssalon = self.geo2apex(ssglat, ssglon, ssheight) |
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# Calculate the magnetic local time (0-24 h range) from apex longitude. |
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# Ensure lists are converted to arrays |
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mlt = (180 + np.asarray(mlon) - ssalon) / 15 % 24 |
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if mlt.shape == (): |
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mlt = np.float64(mlt) |
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return mlt |
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def mlt2mlon(self, mlt, dtime, ssheight=318550): |
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"""Computes the magnetic longitude at the specified MLT and UT. |
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@@ 803-845 (lines=43) @@
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return mlt |
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def mlt2mlon(self, mlt, dtime, ssheight=318550): |
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"""Computes the magnetic longitude at the specified MLT and UT. |
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Parameters |
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---------- |
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mlt : array_like |
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Magnetic local time |
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dtime : :class:`datetime.datetime` |
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Date and time |
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ssheight : float, optional |
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Altitude in km to use for converting the subsolar point from |
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geographic to magnetic coordinates. A high altitude is used |
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to ensure the subsolar point is mapped to high latitudes, which |
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prevents the South-Atlantic Anomaly (SAA) from influencing the MLT. |
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The current default is 50 * 6371, roughly 50 RE. (default=318550) |
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Returns |
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------- |
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mlon : ndarray or float |
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Magnetic longitude [0, 360) (apex and quasi-dipole longitude are |
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always equal) |
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Notes |
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----- |
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To compute the magnetic longitude, we find the apex longitude of the |
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subsolar point at the given time. Then the magnetic longitude of the |
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given point will be computed from the separation in magnetic local time |
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from this point (1 hour = 15 degrees). |
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""" |
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# Get the location of the subsolar point at this time |
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ssglat, ssglon = helpers.subsol(dtime) |
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# Convert the location of the subsolar point to apex coordinates |
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_, ssalon = self.geo2apex(ssglat, ssglon, ssheight) |
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# Calculate the magnetic longitude (0-360 h range) from MLT. |
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# Ensure lists are converted to arrays |
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mlon = (15 * np.asarray(mlt) - 180 + ssalon + 360) % 360 |
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if mlon.shape == (): |
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mlon = np.float64(mlon) |
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return mlon |
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def map_to_height(self, glat, glon, height, newheight, conjugate=False, |
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precision=1e-10): |
aburrell /
apexpy
