Fix spectrum object

.gitignore

@@ -267,3 +267,4 @@ package.json
 
 # Log files generated by 'vagrant up'
 *.log
+.worktree

.pre-commit-config.yaml

@@ -3,7 +3,7 @@ repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
     rev: "v0.14.10"
     hooks:
-      - id: ruff
+      - id: ruff-check
         args: ["--fix"]
       - id: ruff-format
   - repo: https://github.com/PyCQA/isort

changelog/239.feature.rst

@@ -0,0 +1 @@
+Add a new `sunkit_spex.spectrum.spectrum.Spectrum` object to hold spectral data. `~`~sunkit_spex.spectrum.spectrum.Spectrum` is based on `NDCube` and butils on it coordinate aware method and metadata handling.

docs/reference/index.rst

@@ -9,7 +9,7 @@ Software and API.
 .. toctree::
    :maxdepth: 2
 
-
-   fitting
+   spectrum
    models
+   fitting
    legacy

docs/reference/spectrum.rst

@@ -0,0 +1,7 @@
+Models (`sunkit_spex.spectrum`)
+*******************************
+
+``sunkit_spex.spectrum`` module contains objects for holding spectral data
+
+.. automodapi:: sunkit_spex.spectrum
+.. automodapi:: sunkit_spex.spectrum.spectrum

examples/spectrum.py

@@ -0,0 +1,233 @@
+"""
+========
+Spectrum
+========
+
+This example will demonstrate how to store spectral data in `~sunkit_spex.spectrum.Specutm` container
+"""
+
+#####################################################
+#
+# Imports
+
+import numpy as np
+from ndcube import NDMeta
+from ndcube.extra_coords import QuantityTableCoordinate, TimeTableCoordinate
+
+import astropy.units as u
+from astropy.coordinates import SpectralCoord
+from astropy.time import Time
+
+from sunkit_spex.spectrum import Spectrum
+
+rng = np.random.default_rng()
+#####################################################
+#
+# 1D Spectrum
+# -----------
+# Let's being with the simplest case a single spectrum that is a series of measurements as function of wavelength or
+# energy. We will start of by creating some synthetic data and corresponding energy bins as well as some important metadata
+# in this case the exposure time.
+
+data = rng.random(50) * u.ct
+energy = np.linspace(1, 50, 50) * u.keV
+time = Time("2025-02-18T15:08")
+
+exposure_time = 5 * u.s
+
+#####################################################
+#
+# Once we have our synthetic data we can create our metadata container `NDMeta` and `Spectrum` object.
+
+meta = NDMeta()
+meta.add("exposure_time", exposure_time)
+meta.add("date-obs", time)
+
+spec_1d = Spectrum(data, spectral_axis=energy, meta=meta)
+spec_1d
+
+#####################################################
+#
+# One of the key feature of the `Spectrum` object is the ability to slice, crop and perform other operations using
+# standard sliceing methods:
+
+spec_1d_sliced = spec_1d[10:20]
+print(spec_1d_sliced.shape)
+print(spec_1d_sliced.axis_world_coords_values())
+print(spec_1d_sliced.meta)
+print(spec_1d_sliced.spectral_axis)
+
+#####################################################
+#
+# High level coordinate objects such as SkyCoord and SpectralCoord
+
+spec_1d_crop = spec_1d.crop(SpectralCoord(10.5, unit=u.keV), SpectralCoord(20, unit=u.keV))
+print(spec_1d_crop.shape)
+print(spec_1d_crop.axis_world_coords_values())
+print(spec_1d_crop.meta)
+print(spec_1d_crop.spectral_axis)
+
+#####################################################
+#
+# And Quantities
+
+spec_1d_crop_value = spec_1d.crop_by_values((10.5 * u.keV), (20.5 * u.keV))
+print(spec_1d_crop_value.shape)
+print(spec_1d_crop_value.axis_world_coords_values())
+print(spec_1d_crop_value.meta)
+print(spec_1d_crop_value.spectral_axis)
+
+#####################################################
+#
+# 2D Spectrum (spectrogram or time v energy)
+# ------------------------------------------
+# Let build on the previous example by increasing the dimensionality of the data in this case to a spectrogram or a
+# series of spectra as a function of time. Here we will simulate a series of 10 spectra taken over 10 minutes. Again we
+# begin by creating our synthetic data as before but additionally creating the time variable.
+
+data = rng.random((10, 50)) * u.ct
+energy = np.linspace(1, 50, 51) * u.keV
+times = Time("2025-02-18T15:08") + np.arange(10) * u.min
+exposure_time = np.arange(5, 15) * u.s
+
+#####################################################
+#
+# We are also going to demonstrate the  power of the sliceable metadata, so in this example each of the individual
+# spectra have different exposure times (this could be another important information regard the observation)
+
+meta = NDMeta()
+meta.add("exposure_time", exposure_time, axes=(0,))
+
+time_coord = TimeTableCoordinate(times, names="time", physical_types="time")
+energy_coord = QuantityTableCoordinate(energy, names="energy", physical_types="em.energy")
+wcs = (energy_coord & time_coord).wcs
+
+spec_2d_time_energy = Spectrum(data, spectral_axis=energy, wcs=wcs, spectral_axis_index=1, meta=meta)
+
+######################################################
+#
+# Again all standard slicing works
+
+spec_2d_time_energy[2:5]
+spec_2d_time_energy[:, 10:20]
+spec_2d_time_energy_sliced = spec_2d_time_energy[2:5, 10:20]
+
+######################################################
+#
+# We can being to see the usefulness of the sliceable metadata notice how the exposure time entry has been sliced
+# appropriately
+
+print(spec_2d_time_energy_sliced.shape)
+print(spec_2d_time_energy_sliced.axis_world_coords_values())
+print(spec_2d_time_energy_sliced.meta)
+print(spec_2d_time_energy_sliced.spectral_axis)
+
+######################################################
+#
+# The same can be archived using height level coordinate objects
+#
+
+spec_2d_time_energy_crop = spec_2d_time_energy.crop(
+    [SpectralCoord(10, unit=u.keV), Time("2025-02-18T15:10")], [SpectralCoord(20, unit=u.keV), Time("2025-02-18T15:12")]
+)
+
+print(spec_2d_time_energy_crop.shape)
+print(spec_2d_time_energy_crop.axis_world_coords_values())
+print(spec_2d_time_energy_crop.meta)
+print(spec_2d_time_energy_crop.spectral_axis)
+
+######################################################
+#
+# Or Quantities as before
+spec_2d_time_energy_crop_values = spec_2d_time_energy.crop_by_values((10 * u.keV, 2 * u.min), (19.5 * u.keV, 4 * u.min))
+
+print(spec_2d_time_energy_crop_values.shape)
+print(spec_2d_time_energy_crop_values.axis_world_coords_values())
+print(spec_2d_time_energy_crop_values.meta)
+print(spec_2d_time_energy_crop_values.spectral_axis)
+
+#####################################################
+#
+# 2D Spectrum ( e.g. detector v energy)
+# -------------------------------------
+
+data = rng.random((10, 50)) * u.ct
+energy = np.linspace(1, 50, 50) * u.keV
+
+exposure_time = np.arange(10) * u.s
+labels = np.array([f"det_+{chr(97 + i)}" for i in range(10)])
+
+meta = NDMeta()
+meta.add("exposure_time", exposure_time, axes=0)
+meta.add("detector", labels, axes=0)
+
+spec_2d_det_time = Spectrum(data, spectral_axis=energy, spectral_axis_index=1, meta=meta)
+spec_2d_det_time
+
+
+#####################################################
+#
+
+spec_2d_det_time.crop((SpectralCoord(10 * u.keV), None), (SpectralCoord(20 * u.keV), None))
+
+#####################################################
+#
+
+spec_2d_det_time.crop_by_values((10 * u.keV, 0), (20 * u.keV, 2))
+
+#####################################################
+#
+# 3D Spectrum ( e.g. detector v energy v time)
+# --------------------------------------------
+
+# data = rng.random(10, 20, 30) * u.ct
+# energy = np.linspace(1, 31, 31) * u.keV
+#
+# labels = np.array([chr(97 + i) for i in range(10)])
+# exposure_time = np.arange(10 * 20).reshape(10, 20) * u.s
+# times = Time.now() + np.arange(20) * u.s
+#
+# meta = NDMeta()
+# meta.add("exposure_time", exposure_time, axes=(0, 1))
+# meta.add("detector", labels, axes=(0,))
+#
+# spec_3d_det_energy_time = Spectrum(data, spectral_axis=energy, spectral_axis_index=2, meta=meta)
+# spec_3d_det_energy_time.extra_coords.add("time", (0,), times)
+#
+# spec_3d_det_energy_time[:, 10:15, :].meta
+# spec_3d_det_energy_time[2:3, 10:15, :].meta
+
+#####################################################
+#
+# 4D Spectrum ( e.g. spatial v spatial v energy v time)
+# -----------------------------------------------------
+
+# import numpy as np
+# from ndcube import NDMeta
+#
+# import astropy.units as u
+# from astropy.time import Time
+#
+# data = np.random.rand(10, 10, 20, 30) * u.ct
+# energy = np.linspace(1, 31, 31) * u.keV
+# exposure_time = np.arange(20) * u.s
+# times = Time.now() + np.arange(20) * u.s
+#
+# meta = NDMeta()
+# meta.add("exposure_time", exposure_time, axes=(2,))
+#
+# wcs = astropy.wcs.WCS(naxis=2)
+# wcs.wcs.ctype = "HPLT-TAN", "HPLN-TAN"
+# wcs.wcs.cunit = "deg", "deg"
+# wcs.wcs.cdelt = 0.5, 0.4
+# wcs.wcs.crpix = 5, 6
+# wcs.wcs.crval = 0.5, 1
+# wcs.wcs.cname = "HPC lat", "HPC lon"
+#
+# cube = NDCube(data=data, wcs=wcs, meta=meta)
+#
+# # Now instantiate the NDCube
+# spec_4d_lon_lat_time_energy = Spectrum(data, wcs=wcs, spectral_axis=energy, spectral_axis_index=3, meta=meta)
+# spec_4d_lon_lat_time_energy.extra_coords.add("time", (2,), times)
+#
+# spec_4d_lon_lat_time_energy

pyproject.toml

@@ -26,7 +26,7 @@ dependencies = [
     "scipy>=1.12",
     "sunpy>=7.0",
     "xarray>=2023.12",
-    "gwcs>=0.21.0",
+    "gwcs<1.0.0", #until https://github.com/sunpy/ndcube/issues/913 is resolved
     "ndcube>=2.3",
 ]
 

pytest.ini

@@ -40,6 +40,6 @@ filterwarnings =
     # Oldestdeps issues
     ignore:`finfo.machar` is deprecated:DeprecationWarning
     ignore:Please use `convolve1d` from the `scipy.ndimage` namespace, the `scipy.ndimage.filters` namespace is deprecated.:DeprecationWarning
-    ignore::pyparsing.warnings.PyparsingDeprecationWarning
     ignore::FutureWarning:arviz.*
     ignore:The isiterable function.*:astropy.utils.exceptions.AstropyDeprecationWarning
+    ignore:'datfix' made the change:astropy.wcs.wcs.FITSFixedWarning