freefree.py: Update to use "sky" module; cleanups

1 files changed, 59 insertions, 104 deletions

diff --git a/fg21sim/galactic/freefree.py b/fg21sim/galactic/freefree.py
index 2db6f84..d3c663f 100644
--- a/fg21sim/galactic/freefree.py
+++ b/fg21sim/galactic/freefree.py
@@ -28,10 +28,8 @@ References
 
 import os
 import logging
-from datetime import datetime, timezone
 
 import numpy as np
-from astropy.io import fits
 import astropy.units as au
 
 from ..sky import get_sky
@@ -51,8 +49,8 @@ class FreeFree:
 
     Parameters
     ----------
-    configs : ConfigManager object
-        An `ConfigManager` object contains default and user configurations.
+    configs : `~ConfigManager`
+        An ``ConfigManager`` object contains default and user configurations.
         For more details, see the example config specification.
 
     Attributes
@@ -60,15 +58,24 @@ class FreeFree:
     TODO
     """
     # Component name
+    comp = "galactic/freefree"
     name = "Galactic free-free"
 
     def __init__(self, configs):
         self.configs = 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/freefree"
+        """
+        Load the configs and set the corresponding class attributes.
+        """
+        comp = self.compID
         self.halphamap_path = self.configs.get_path(comp+"/halphamap")
         self.halphamap_unit = au.Unit(
             self.configs.getn(comp+"/halphamap_unit"))
@@ -79,15 +86,11 @@ class FreeFree:
         self.halpha_abs_th = self.configs.getn(comp+"/halpha_abs_th")  # [mag]
         self.Te = self.configs.getn(comp+"/electron_temperature")  # [K]
         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")
 
@@ -95,15 +98,14 @@ class FreeFree:
         """
         Load the Hα map, and 100-μm dust map.
         """
-        sky = get_sky(self.configs)
         logger.info("Loading H[alpha] map ...")
-        self.halphamap = sky.open(self.halphamap_path)
+        self.halphamap = self.sky.open(self.halphamap_path)
         # Validate input map unit
         if self.halphamap_unit != au.Unit("Rayleigh"):
             raise ValueError("unsupported Halpha map unit: {0}".format(
                 self.halphamap_unit))
         logger.info("Loading dust map ...")
-        self.dustmap = sky.open(self.dustmap_path)
+        self.dustmap = self.sky.open(self.dustmap_path)
         # Validate input map unit
         if self.dustmap_unit != au.Unit("MJy / sr"):
             raise ValueError("unsupported dust map unit: {0}".format(
@@ -118,7 +120,7 @@ class FreeFree:
         """
         if hasattr(self, "_dust_corrected") and self._dust_corrected:
             return
-        #
+
         logger.info("Correct H[alpha] map for dust absorption")
         logger.info("Effective dust fraction: {0}".format(self.f_dust))
         # Mask the regions where the true Halpha absorption is uncertain.
@@ -188,64 +190,26 @@ class FreeFree:
         h2f = 38.86 * a * nu**(-2.1) * 10**(290/self.Te) * self.Te**0.667
         return h2f
 
-    def _make_filepath(self, **kwargs):
+    def _outfilepath(self, frequency, **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
+        Generate the path/filename to the output file for writing
+        the simulate sky images.
 
-    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.
+        Parameters
+        ----------
+        frequency : float
+            The frequency of the output sky image.
+            Unit: [MHz]
 
         Returns
         -------
-        outfile : str
-            The (absolute) path to the output sky map file.
+        filepath : str
+            The generated filepath for the output sky 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 = get_sky(configs=self.configs)
-        sky.data = skymap
-        sky.header = header
-        sky.write(outfile, clobber=self.clobber, checksum=self.checksum)
-        return outfile
+        filename = self.filename_pattern.format(
+            prefix=self.prefix, frequency=frequency, **kwargs)
+        filepath = os.path.join(self.output_dir, filename)
+        return filepath
 
     def preprocess(self):
         """
@@ -260,70 +224,61 @@ class FreeFree:
         """
         if hasattr(self, "_preprocessed") and self._preprocessed:
             return
-        #
+
         logger.info("{name}: preprocessing ...".format(name=self.name))
         self._load_maps()
-        # Correct for dust absorption
         self._correct_dust_absorption()
-        #
+
         self._preprocessed = True
 
     def simulate_frequency(self, frequency):
         """
         Simulate the free-free map at the specified frequency.
 
+        Parameters
+        ----------
+        frequency : float
+            The frequency where to simulate the emission map.
+            Unit: [MHz]
+
         Returns
         -------
-        skymap_f : 1D `~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.
         """
-        self.preprocess()
-        #
-        logger.info("Simulating {name} map at {freq} ({unit}) ...".format(
-            name=self.name, freq=frequency, unit=self.freq_unit))
+        logger.info("Simulating {name} map at {freq:.2f} [MHz] ...".format(
+            name=self.name, freq=frequency))
+        sky = self.sky.copy()
+        sky.frequency = frequency
         ratio_K_R = self._calc_halpha_to_freefree(frequency)
-        skymap_f = self.halphamap.data * ratio_K_R
-        #
-        if self.save:
-            filepath = self.output(skymap_f, frequency)
-        else:
-            filepath = None
-        return (skymap_f, filepath)
+        sky.data = self.halphamap * ratio_K_R
+        logger.info("Done simulate map at %.2f [MHz]." % frequency)
+        return sky
 
     def simulate(self, frequencies=None):
         """
-        Simulate the synchrotron map at the specified frequencies.
+        Simulate the emission maps.
 
         Parameters
         ----------
         frequencies : float, or list[float]
-            The frequencies where to simulate the foreground map.
+            The frequencies where to simulate the emission 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."""
-        pass
+        logger.info("{name}: postprocessing ...".format(name=self.name))
+        logger.info("^_^ nothing to do :-)")