snr.py: Update to use "sky" module

XXX: significant cleanups required, to make `SkyPatch` works!

1 files changed, 39 insertions, 114 deletions

diff --git a/fg21sim/galactic/snr.py b/fg21sim/galactic/snr.py
index 18d8262..e77e24e 100644
--- a/fg21sim/galactic/snr.py
+++ b/fg21sim/galactic/snr.py
@@ -25,13 +25,10 @@ References
 
 import os
 import logging
-from datetime import datetime, timezone
 
 import numpy as np
-from astropy.io import fits
-from astropy.coordinates import SkyCoord
-import astropy.units as au
 import pandas as pd
+from astropy.coordinates import SkyCoord
 
 from ..sky import get_sky
 from ..utils.wcs import make_wcs
@@ -69,29 +66,33 @@ class SuperNovaRemnants:
     TODO
     """
     # Component name
+    compID = "galactic/snr"
     name = "Galactic SNRs"
 
     def __init__(self, configs):
         self.configs = configs
-        self.sky = get_sky(configs)
         self._set_configs()
 
+        self.sky = get_sky(configs)
+        self.sky.add_header("CompID", self.compID, "Emission component ID")
+        self.sky.add_header("CompName", self.name, "Emission component")
+        self.sky.add_header("BUNIT", "K", "[Kelvin] Data unit")
+        self.sky.creator = __name__
+
     def _set_configs(self):
-        """Load the configs and set the corresponding class attributes."""
-        comp = "galactic/snr"
+        """
+        Load the configs and set the corresponding class attributes.
+        """
+        comp = self.compID
         self.catalog_path = self.configs.get_path(comp+"/catalog")
         self.catalog_outfile = self.configs.get_path(comp+"/catalog_outfile")
         self.resolution = self.configs.getn(comp+"/resolution")  # [ arcsec ]
         self.prefix = self.configs.getn(comp+"/prefix")
-        self.save = self.configs.getn(comp+"/save")
         self.output_dir = self.configs.get_path(comp+"/output_dir")
         #
         self.filename_pattern = self.configs.getn("output/filename_pattern")
-        self.use_float = self.configs.getn("output/use_float")
-        self.checksum = self.configs.getn("output/checksum")
         self.clobber = self.configs.getn("output/clobber")
         self.frequencies = self.configs.frequencies  # [MHz]
-        self.freq_unit = au.Unit(self.configs.getn("frequency/unit"))
         logger.info("Loaded and set up configurations")
 
     def _load_catalog(self):
@@ -112,8 +113,8 @@ class SuperNovaRemnants:
             self.catalog_path))
         logger.info("SNRs catalog data: {0} objects, {1} columns".format(
             nrow, ncol))
-        # The flux densities are given at 1 GHz
-        self.catalog_flux_freq = (1.0*au.GHz).to(self.freq_unit).value
+        # The flux densities are given at 1 [GHz] -> 1000 [MHz]
+        self.catalog_flux_freq = 1e3  # [MHz]
         # Convert ``size_major`` and ``size_minor`` from unit [arcmin]
         # to [arcsec]
         self.catalog["size_major"] *= AUC.arcmin2arcsec
@@ -312,7 +313,8 @@ class SuperNovaRemnants:
             ``data.key``.
             e.g., elements of `self.catalog.itertuples()`
         frequency : float
-            The simulation frequency (unit: `self.freq_unit`).
+            The simulation frequency.
+            Unit: [MHz]
 
         Returns
         -------
@@ -336,65 +338,6 @@ class SuperNovaRemnants:
         val = val * Tb
         return (idx, val)
 
-    def _make_filepath(self, **kwargs):
-        """
-        Make the path of output file according to the filename pattern
-        and output directory loaded from configurations.
-        """
-        data = {
-            "prefix": self.prefix,
-        }
-        data.update(kwargs)
-        filename = self.filename_pattern.format(**data)
-        filepath = os.path.join(self.output_dir, filename)
-        return filepath
-
-    def _make_header(self):
-        """
-        Make the header with detail information (e.g., parameters and
-        history) for the simulated products.
-        """
-        header = fits.Header()
-        header["COMP"] = (self.name, "Emission component")
-        header["BUNIT"] = ("K", "data unit is Kelvin")
-        header["CREATOR"] = (__name__, "File creator")
-        # TODO:
-        history = []
-        comments = []
-        for hist in history:
-            header.add_history(hist)
-        for cmt in comments:
-            header.add_comment(cmt)
-        self.header = header
-        logger.info("Created FITS header")
-
-    def output(self, skymap, frequency):
-        """
-        Write the simulated free-free map to disk with proper header
-        keywords and history.
-
-        Returns
-        -------
-        outfile : str
-            The (absolute) path to the output sky map file.
-        """
-        outfile = self._make_filepath(frequency=frequency)
-        if not hasattr(self, "header"):
-            self._make_header()
-        header = self.header.copy()
-        header["FREQ"] = (frequency, "Frequency [ MHz ]")
-        header["DATE"] = (
-            datetime.now(timezone.utc).astimezone().isoformat(),
-            "File creation date"
-        )
-        if self.use_float:
-            skymap = skymap.astype(np.float32)
-        sky = self.sky.copy()
-        sky.data = skymap
-        sky.header = header
-        sky.write(outfile, clobber=self.clobber, checksum=self.checksum)
-        return outfile
-
     def preprocess(self):
         """
         Perform the preparation procedures for the final simulations.
@@ -403,19 +346,18 @@ class SuperNovaRemnants:
         ----------
         _preprocessed : bool
             This attribute presents and is ``True`` after the preparation
-            procedures are performed, which indicates that it is ready to
-            do the final simulations.
+            procedures are performed.
         """
         if hasattr(self, "_preprocessed") and self._preprocessed:
             return
-        #
+
         logger.info("{name}: preprocessing ...".format(name=self.name))
         self._load_catalog()
         self._filter_catalog()
         self._add_random_rotation()
         # Simulate the template maps for each SNR
         self._simulate_templates()
-        #
+
         self._preprocessed = True
 
     def simulate_frequency(self, frequency):
@@ -426,39 +368,31 @@ class SuperNovaRemnants:
         Parameters
         ----------
         frequency : float
-            The simulation frequency (unit: `self.freq_unit`).
+            The simulation frequency.
+            Unit: [MHz]
 
         Returns
         -------
-        skymap_f : 1D/2D `~numpy.ndarray`
-            The sky map at the input frequency.
-        filepath : str
-            The (absolute) path to the output sky map if saved,
-            otherwise ``None``.
+        sky : `~SkyBase`
+            The simulated sky image as a new sky instance.
 
         See Also
         --------
         `self._simulate_template()` for more detailed description.
         """
-        self.preprocess()
-        #
-        logger.info("Simulating {name} map at {freq} ({unit}) ...".format(
-            name=self.name, freq=frequency, unit=self.freq_unit))
-        skymap_f = np.zeros(self.sky.shape)
+        logger.info("Simulating {name} map at {freq:.2f} [MHz] ...".format(
+            name=self.name, freq=frequency))
+        sky = self.sky.copy()
+        sky.frequency = frequency
         for row in self.catalog.itertuples():
             index, value = self._simulate_single(row, frequency)
-            skymap_f[index] += value
-        #
-        if self.save:
-            filepath = self.output(skymap_f, frequency)
-        else:
-            filepath = None
-        return (skymap_f, filepath)
+            sky.data[index] += value
+        logger.info("Done simulate map at %.2f [MHz]." % frequency)
+        return sky
 
     def simulate(self, frequencies=None):
         """
-        Simulate the sky maps of all Galactic SNRs emission at every
-        specified frequency.
+        Simulate the sky maps of all Galactic SNRs emission.
 
         Parameters
         ----------
@@ -466,27 +400,18 @@ class SuperNovaRemnants:
             The frequencies where to simulate the foreground map.
             Unit: [MHz]
             Default: None (i.e., use ``self.frequencies``)
-
-
-        Returns
-        -------
-        skymaps : list[1D `~numpy.ndarray`]
-            List of sky maps at each frequency.
-        paths : list[str]
-            List of (absolute) path to the output sky maps.
         """
-        if frequencies is not None:
-            frequencies = np.array(frequencies, ndmin=1)
-        else:
+        if frequencies is None:
             frequencies = self.frequencies
+        else:
+            frequencies = np.array(frequencies, ndmin=1)
 
-        skymaps = []
-        paths = []
+        logger.info("Simulating {name} ...".format(name=self.name))
         for freq in frequencies:
-            skymap_f, outfile = self.simulate_frequency(freq)
-            skymaps.append(skymap_f)
-            paths.append(outfile)
-        return (skymaps, paths)
+            sky = self.simulate_frequency(freq)
+            outfile = self._outfilepath(frequency=freq)
+            sky.write(outfile)
+        logger.info("Done simulate {name}!".format(name=self.name))
 
     def postprocess(self):
         """Perform the post-simulation operations before the end."""