`planetmapper.utils`

Various general helpful utilities.

planetmapper.utils.format_radec_axes(ax: Axes, dec: float, dms_ticks: bool = True, add_axis_labels: bool = True, aspect_adjustable: Literal['box', 'datalim'] | None = 'datalim') → None[source]

Format an axis to display RA/Dec coordinates nicely.

Parameters:

ax – Matplotlib axis to format.
dec – Declination in degrees of centre of axis.
dms_ticks – Toggle between showing ticks as degrees, minutes and seconds (e.g. 12°34′56″) or decimal degrees (e.g. 12.582).
add_axis_labels – Add axis labels.
aspect_adjustable – Set adjustable parameter when setting the aspect ratio. Passed to matplotlib.axes.Axes.set_aspect(). Set to None to skip setting the aspect ratio (generally this is only recommended if you’re setting the aspect ratio yourself).

class planetmapper.utils.DMSFormatter[source]

Bases: FuncFormatter

Matplotlib tick formatter to display angular values as degrees, minutes and seconds e.g. 12°34′56″. Designed to work with DMSLocator.

ax = plt.cga()

ax.yaxis.set_major_locator(planetmapper.utils.DMSLocator())
ax.yaxis.set_major_formatter(planetmapper.utils.DMSFormatter())

ax.xaxis.set_major_locator(planetmapper.utils.DMSLocator())
ax.xaxis.set_major_formatter(planetmapper.utils.DMSFormatter())

class planetmapper.utils.DMSLocator[source]

Bases: Locator

Matplotlib tick locator to display angular values as degrees, minutes and seconds. Designed to work with DMSFormatter.

ax = plt.cga()

ax.yaxis.set_major_locator(planetmapper.utils.DMSLocator())
ax.yaxis.set_major_formatter(planetmapper.utils.DMSFormatter())

ax.xaxis.set_major_locator(planetmapper.utils.DMSLocator())
ax.xaxis.set_major_formatter(planetmapper.utils.DMSFormatter())

planetmapper.utils.decimal_degrees_to_dms(decimal_degrees: float) → tuple[int, int, float][source]

Get degrees, minutes, seconds from decimal degrees.

decimal_degrees_to_dms(-11.111) returns (-11.0, 6.0, 39.6).

Parameters:: decimal_degrees – Decimal degrees.
Returns:: (degrees, minutes, seconds) tuple

planetmapper.utils.decimal_degrees_to_dms_str(decimal_degrees: float, seconds_fmt: str = 'g') → str[source]

Create nicely formatted DMS string from decimal degrees value (e.g. '12°34′56″').

Uses decimal_degrees_to_dms() to perform the conversion.

Parameters:

decimal_degrees – Decimal degrees.
seconds_fmt – Optionally specify a format string for the seconds part of the returned value. For example, seconds_fmt='.3f' will fix three decimal places for the fractional part of the seconds value. Note that the integral part of the seconds value will always be zero-padded to two digits, so seconds_fmt='.3f' will return seconds as e.g. 01.234.

Returns:

String representing the degrees, minutes, seconds of the angle.

class planetmapper.utils.ignore_warnings(*warning_strings: str, **kwargs)[source]

Bases: catch_warnings

Context manager to ignore general warnings using warnings.filterwarnings.

class planetmapper.utils.filter_fits_comment_warning(*, record=False, module=None, action=None, category=<class 'Warning'>, lineno=0, append=False)[source]

Bases: catch_warnings

Context manager to hide FITS Card is too long, comment will be truncated warnings.

planetmapper.utils.normalise(values: ndarray | Sequence[float], top: float = 1.0, bottom: float = 0.0, single_value: float | None = None) → ndarray[source]

Normalise iterable.

Parameters:

values – Iterable of values to normalise.
top – Top of normalised range.
bottom – Bottom of normalised range.
single_value – If all values are the same, return this value.

Returns:

Normalised values.

planetmapper.utils.check_path(path: str) → None[source]

Checks if file path’s directory tree exists, and creates it if necessary.

Assumes path is to a file if os.path.split(path)[1] contains ‘.’, otherwise assumes path is to a directory.

exception planetmapper.utils.GetWavelengthsError[source]

Bases: ValueError

Error raised when wavelength information cannot be extracted from a FITS header.

planetmapper.utils.generate_wavelengths_from_header(header: Header | dict, *, check_ctype: bool = True, axis: int = 3) → ndarray[source]

Generate wavelength array from keyword values in a FITS Header.

This uses the NAXIS3, CRVAL3, CDELT3 (or CD3_3) and CRPIX3 keywords to generate the wavelength array described by the Header. The axis to generate wavelengths for can be customised using the axis parameter.

By default, this function will raise an exception if the CTYPE of the axis is not ‘WAVE’. This can be disabled by setting check_ctype to False.

See the JWST documentation for an an example of how the wavelength array can be generated from the FITS Header.

Parameters:

header – FITS Header object (or dictionary).
check_ctype – Check that the CTYPE of the axis is ‘WAVE’.
axis – Axis to generate wavelengths for, using FITS (1-based) counting. This defaults to 3.

Returns:

Wavelength array.

Raises:

GetWavelengthsError – If the wavelength array cannot be generated from the FITS Header.

planetmapper.utils

`planetmapper.utils`