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SunPy module documentation

usr_sunpy

User functions. - SunPy Version: 0.9.3

usr_sunpy.basic

read_sdo 

1
read_sdo(filename)

Example of reading from a FITS file. Print the filename and dimensions.

Returns a sunpy GenericMap or subclass(e.g. HMIMap) object - data - a 2D numpy ndarray data[i, j]: i from the bottom(y), j from te left(x). - meta - a dict of the original image headr tags.

[See also] - help(sunpy.map.GenericMap) - http://docs.sunpy.org/en/stable/code_ref/map.html#using-map-objects

tai 

1
tai(*timestr)

Warp time strings as TAI time.

Parameters - timestr: time strings e.g. '2010-01-01T00:00:00', '2010.01.01_00:00:00_TAI'

Returns - len(timestr) == 1: a TAI Time object - len(timestr) > 1: a list of TAI Time objects

[See also] - http://docs.astropy.org/en/stable/time/ - http://docs.sunpy.org/en/stable/guide/time.html

aiaprep_usr 

1
aiaprep_usr(aiamap, order=3)

Modified sunpy.instr.aia.aiaprep()

Processes a level 1 ~sunpy.map.sources.sdo.AIAMap into a level 1.5 ~sunpy.map.sources.sdo.AIAMap. Rotates, scales and translates the image so that solar North is aligned with the y axis, each pixel is 0.6 arcsec across, and the center of the sun is at the center of the image. The actual transformation is done by Map's :meth:~sunpy.map.mapbase.GenericMap.rotate method.

This function is similar in functionality to aia_prep() in SSWIDL, but it does not use the same transformation to rotate the image and it handles the meta data differently. It should therefore not be expected to produce the same results.

Parameters

aiamap : ~sunpy.map.sources.sdo.AIAMap instance A sunpy.map.Map from AIA

Returns

newmap : A level 1.5 copy of ~sunpy.map.sources.sdo.AIAMap

Notes

This routine makes use of Map's :meth:~sunpy.map.mapbase.GenericMap.rotate method, which modifies the header information to the standard PCi_j WCS formalism. The FITS header resulting in saving a file after this procedure will therefore differ from the original file.

usr_sunpy.plot

  • SunPy Version: 0.9.3
  • Reference http://docs.sunpy.org/en/stable/code_ref/map.html
  • Change log:
    • 2018-10-11
      • Change parameter list of plot_map(), plot_vmap(), proj_matrix().
      • Change return value of _get_image_params() from a tuple to a dict.
      • Adjust positions of colorbar & title.
      • Fix docs.

plot_map 

1
plot_map(smap, ax=None, coords=None, annotate=True, title=True, colorbar=True, grid=True, grid_color='yellow', grid_ls=':', grid_lw=0.8, grid_alpha=0.5, **kwargs)

Plot image.

[Plot Function] - plot_map(smap, kwargs) -> use smap.plot(), imshow from matplotlib - plot_map(smap, coords=(X, Y), kwargs) -> pcolormesh from matplotlib

Parameters - smap: a sunpy GenericMap - ax: a matplotlib Axes object - coords: tuple or list of ndarrays: (X, Y) - grid: bool or ~astropy.units.Quantity(spacing), zorder = 90 - grid_color: grid color - grid_ls: grid line stlye - grid_lw: grid line width - grid_alpha: grid alpha - cmap: name of color map - kwargs: dict, matplotlib kwargs If coords is None(default), use kwargs of imshow, else of pcolormesh.

Returns a matplotlib image object

[See also] http://docs.sunpy.org/en/stable/code_ref/map.html#sunpy.map.mapbase.GenericMap.plot

plot_vmap 

1
plot_vmap(mapu, mapv, mapc, ax=None, coords=None, cmap='binary', iskip='auto', jskip='auto', cmin=0.0, cmax=None, vmin=None, vmax=1000.0, scale_units='xy', scale=20.0, minlength=0.05, width=0.003, headlength=6.5, headwidth=5, headaxislength=3.5, **kwargs)

Quiver plot of (U, V).

[Plot Function] quiver from matplotlib, zorder(default) = 100

Parameters - mapu: a sunpy GenericMap of U - mapv: a sunpy GenericMap of V - mapc: a sunpy GenericMap to set color values - ax: matplotlib axes object - coords: tuple or list of 2D ndarrays: (X, Y) - iskip, jskip: 'auto' or number of skipped points - cmin: where mapc.data < cmin => set U, V to zero - cmax: where mapc.data > cmax => set U, V to zero - vmin: clip norm(U, V) to vmin - vmax: clip norm(U, V) to vmax - cmap: name of a color map - scale_units, ..., **kwargs: kwargs of quiver

Returns a matplotlib artist(image object)

[See also] https://matplotlib.org/devdocs/api/_as_gen/matplotlib.axes.Axes.quiver.html#matplotlib-axes-axes-quiver

image_to_helio 

1
image_to_helio(*smap)

Transform maps from image-coordinate to helio-coordinate. - Helo-coordinate: Helioprojective(Cartesian) system - Matrix: A22 or A33 get from usr_sunpy.proj_matrix - Unit: arcsec

Parameters - smap: GenericMap, one or three elements. - For scalar: image_to_helio(smap) - For vectors: image_to_helio(smapx, smapy, smapz)

Returns - For scalar: x_h, y_h (type: ndarray) - For vectors: smapx_h, smapy_h, smapz_h (type: GenericMap)

[See also] http://docs.sunpy.org/en/stable/code_ref/coordinates.html#sunpy-coordinates

proj_matrix 

1
proj_matrix(P, L0, B0, Lc, Bc, *dim)
  • For coords: (x, y)_helio = A22.T.I * (x, y)_image
  • For vectors: (U, V, W)_helio = A33 * (U, V, W)_image

A33 = [[a11, a12, a13], [a21, a22, a23], [a31, a32, a33]]

Parameters - P: the angle of the northern extremity, CCW from the north point of the disk. - L0: the longitude of the center of the disk. - B0: the latitude of the center of the disk. - Lc: the longitude of the the referenced point. - Bc: the latitude of the referenced point.

Returns elements of a 2D array (use values instead of arrays just for easy reading & comparison) - default: a11, a12, a13, a21, a22, a23, a31, a32, a33 - dim=2: a11, a12, a21, a22

[Reference] http://link.springer.com/10.1007/BF00158295

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