diff options
Diffstat (limited to 'astro/fits')
| -rwxr-xr-x | astro/fits/fitsimage.py | 56 |
1 files changed, 48 insertions, 8 deletions
diff --git a/astro/fits/fitsimage.py b/astro/fits/fitsimage.py index ca980a9..5b416a2 100755 --- a/astro/fits/fitsimage.py +++ b/astro/fits/fitsimage.py @@ -21,12 +21,15 @@ class FITSImage: handles single-frequency single-polarized image cube (NAXIS=3, 4), e.g., created by WSClean. """ - def __init__(self, infile): + def __init__(self, infile, pixelsize=None): + self.infile = infile with fits.open(infile) as f: self.header = f[0].header self.data = f[0].data self.ndim = self.data.ndim self.shape = self.data.shape + if pixelsize is not None: + self.pixelsize = pixelsize # [arcsec] @property def bunit(self): @@ -76,6 +79,39 @@ class FITSImage: # NAXIS=4: [STOKES=1, FREQ=1, Y, X] self.data[0, 0, :, :] = value + @property + def pixelsize(self): + """ + Image pixel size, in units of [arcsec] + """ + if hasattr(self, "_pixelsize"): + return self._pixelsize + + try: + return self.header["PixSize"] # [arcsec] + except KeyError: + try: + return abs(self.header["CDELT1"]) * 3600 # [deg] -> [arcsec] + except KeyError: + return None + + @pixelsize.setter + def pixelsize(self, value): + # Unit: [arcsec] + self._pixelsize = value + + @property + def fov(self): + """ + Image FoV coverage: (fov_x, fov_y) + Unit: [deg] + """ + pixelsize = self.pixelsize + if pixelsize: + return (self.Nx*pixelsize/3600, self.Ny*pixelsize/3600) + else: + return None + def write(self, outfile, clobber=False): self.header.add_history(" ".join(sys.argv)) hdu = fits.PrimaryHDU(data=self.data, header=self.header) @@ -91,7 +127,11 @@ def cmd_info(args): """ fimage = FITSImage(args.infile) print("Image size: %dx%d" % (fimage.Nx, fimage.Ny)) - print("Data unit: %s" % fimage.bunit) + print("Data unit: [%s]" % fimage.bunit) + pixelsize = fimage.pixelsize + if pixelsize: + print("Pixel size: %.1f [arcsec]" % pixelsize) + print("Field of view: (%.2f, %.2f) [deg]" % fimage.fov) data = fimage.image if args.abs: data = np.abs(data) @@ -107,12 +147,12 @@ def cmd_info(args): iqr = np.diff(np.percentile(data, q=(25, 75))) mad = np.median(np.abs(data - median)) rms = np.sqrt(np.mean(data**2)) - print("mean: %-12.6e" % mean) - print("median: %-12.6e" % median) - print("std: %-12.6e (standard deviation)" % std) - print("iqr: %-12.6e (interquartile range)" % iqr) - print("mad: %-12.6e (median absolute deviation)" % mad) - print("rms: %-12.6e (root-mean-squared)" % rms) + print("mean: %13.6e" % mean) + print("median: %13.6e" % median) + print("std: %13.6e (standard deviation)" % std) + print("iqr: %13.6e (interquartile range)" % iqr) + print("mad: %13.6e (median absolute deviation)" % mad) + print("rms: %13.6e (root-mean-squared)" % rms) def cmd_add(args): |