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-rwxr-xr-xastro/eor_window.py2
-rwxr-xr-xastro/ps2d.py40
2 files changed, 21 insertions, 21 deletions
diff --git a/astro/eor_window.py b/astro/eor_window.py
index 2a557c9..71f4cc2 100755
--- a/astro/eor_window.py
+++ b/astro/eor_window.py
@@ -80,7 +80,7 @@ class PS2D:
with fits.open(infile) as f:
self.header = f[0].header
self.ps2d = f[0].data[0, :, :]
- self.ps2d_err = (f[0].data[1, :, :] + f[0].data[2, :, :]) / 2
+ self.ps2d_err = f[0].data[1, :, :]
self.freqc = self.header["Freq_C"]
self.freqmin = self.header["Freq_Min"]
self.freqmax = self.header["Freq_Max"]
diff --git a/astro/ps2d.py b/astro/ps2d.py
index a4c85f9..a4f25ab 100755
--- a/astro/ps2d.py
+++ b/astro/ps2d.py
@@ -131,7 +131,7 @@ class PS2D:
frequencies at each image slice [MHz]
meanstd : bool, optional
if ``True``, calculate the mean and standard deviation for each
- power bin instead of the median and 68% percentile range.
+ power bin instead of the median and 1.4826*MAD.
unit : str, optional
unit of the cube data; will be used to determine the power spectrum
unit as well as the plot labels.
@@ -214,10 +214,10 @@ class PS2D:
Returns
-------
ps2d : 3D `~numpy.ndarray`
- 3D array of shape (3, n_k_los, n_k_perp) including the median
- and lower and upper errors (68% percentile range).
- If ``self.meanstd=True`` then the mean and standard deviation
- are calculated instead.
+ 3D array of shape (3, n_k_los, n_k_perp) including:
+ + average (median / mean)
+ + error (1.4826*MAD / standard deviation)
+ + number of averaging cells
Attributes
----------
@@ -226,7 +226,8 @@ class PS2D:
logger.info("Calculating 2D power spectrum ...")
n_k_perp = len(self.k_perp)
n_k_los = len(self.k_los)
- ps2d = np.zeros(shape=(3, n_k_los, n_k_perp)) # value, errl, erru
+ # PS2D's 3 layers: value, error, number of averaging cells
+ ps2d = np.zeros(shape=(3, n_k_los, n_k_perp))
eps = 1e-8
ic_xy = (np.abs(self.k_xy) < eps).nonzero()[0][0]
@@ -243,16 +244,15 @@ class PS2D:
for s in range(n_k_los):
iz = (p_z == s).nonzero()[0]
cells = np.concatenate([self.ps3d[z, iy, ix] for z in iz])
+ ps2d[2, s, r] = len(cells)
if self.meanstd:
ps2d[0, s, r] = cells.mean()
- std = cells.std()
- ps2d[1, s, r] = std
- ps2d[2, s, r] = std
+ ps2d[1, s, r] = cells.std()
else:
- median, q16, q84 = np.percentile(cells, q=(50, 16, 84))
+ median = np.median(cells)
+ mad = np.median(np.abs(cells - median))
ps2d[0, s, r] = median
- ps2d[1, s, r] = median - q16
- ps2d[2, s, r] = q84 - median
+ ps2d[1, s, r] = mad * 1.4826
self.ps2d = ps2d
return ps2d
@@ -280,7 +280,7 @@ class PS2D:
title_err = "Error (standard deviation)"
else:
title = "2D Power Spectrum (median)"
- title_err = "Error (68% percentile range)"
+ title_err = "Error (1.4826*MAD)"
# median/mean
mappable = ax.pcolormesh(x[1:], y[1:],
@@ -295,10 +295,9 @@ class PS2D:
cb = ax.figure.colorbar(mappable, ax=ax, pad=0.01, aspect=30)
cb.ax.set_xlabel(r"[%s$^2$ Mpc$^3$]" % self.unit)
- # error (68% percentile range / standard deviation)
- error = 0.5 * (self.ps2d[1, :, :] + self.ps2d[2, :, :])
+ # error
mappable = ax_err.pcolormesh(x[1:], y[1:],
- np.log10(error[1:, 1:]),
+ np.log10(self.ps2d[1, 1:, 1:]),
cmap=colormap)
mappable.set_clim(vmin, vmax)
ax_err.set(xscale="log", yscale="log",
@@ -474,9 +473,10 @@ class PS2D:
if self.meanstd:
hdr["AvgType"] = ("mean + standard deviation", "average type")
else:
- hdr["AvgType"] = ("median + 68% percentile range", "average type")
+ hdr["AvgType"] = ("median + 1.4826*MAD", "average type")
- hdr["WINDOW"] = (self.window_name, "window applied along LoS")
+ hdr["WINDOW"] = (self.window_name,
+ "window applied along frequency axis")
# Physical coordinates: IRAF LTM/LTV
# Li{Image} = LTMi_i * Pi{Physical} + LTVi
@@ -527,8 +527,8 @@ def main():
parser.add_argument("-m", "--mean-std", dest="meanstd",
action="store_true",
help="calculate the mean and standard deviation " +
- "for each averaged annulus instead of the median, " +
- "16%% and 84%% percentiles (i.e., 68%% error)")
+ "for each averaged annulus instead of the median " +
+ "and 1.4826*MAD")
parser.add_argument("-P", "--no-plot", dest="noplot", action="store_true",
help="do NOT plot the 2D power spectrum")
parser.add_argument("-p", "--pixelsize", dest="pixelsize", type=float,