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-rwxr-xr-xastro/21cm/cube_mean.py35
l---------astro/21cm/freq2z.py1
-rwxr-xr-xastro/21cm/z2freq.py80
3 files changed, 116 insertions, 0 deletions
diff --git a/astro/21cm/cube_mean.py b/astro/21cm/cube_mean.py
new file mode 100755
index 0000000..9ff33d4
--- /dev/null
+++ b/astro/21cm/cube_mean.py
@@ -0,0 +1,35 @@
+#!/usr/bin/env python3
+#
+# Copyright (c) 2017 Weitian LI <weitian@aaronly.me>
+# MIT License
+#
+
+"""
+Calculate the mean values of the cube.
+"""
+
+import os
+import sys
+import argparse
+
+import numpy as np
+
+
+def main():
+ parser = argparse.ArgumentParser(
+ description="Calculate the mean value of the data cube")
+ parser.add_argument("-d", "--dtype", default="float32",
+ help="NumPy dtype of data cubes (default: float32)")
+ parser.add_argument("infiles", nargs="+", help="input data cubes")
+ args = parser.parse_args()
+
+ print("# filename: mean side_length")
+ for f in args.infiles:
+ cube = np.fromfile(open(f, "rb"), dtype=args.dtype)
+ sidelen = round(cube.shape[0] ** (1.0/3))
+ mean = cube.mean()
+ print("%s:\t%g\t\t%d" % (f, mean, sidelen))
+
+
+if __name__ == "__main__":
+ main()
diff --git a/astro/21cm/freq2z.py b/astro/21cm/freq2z.py
new file mode 120000
index 0000000..aa9eb7c
--- /dev/null
+++ b/astro/21cm/freq2z.py
@@ -0,0 +1 @@
+z2freq.py \ No newline at end of file
diff --git a/astro/21cm/z2freq.py b/astro/21cm/z2freq.py
new file mode 100755
index 0000000..454a425
--- /dev/null
+++ b/astro/21cm/z2freq.py
@@ -0,0 +1,80 @@
+#!/usr/bin/env python3
+#
+# Copyright (c) 2017 Weitian LI <weitian@aaronly.me>
+# MIT License
+#
+
+"""
+Convert redshifts to the observed frequency of the 21 cm signal,
+and vice versa.
+"""
+
+import os
+import sys
+import argparse
+
+import numpy as np
+
+
+prog = os.path.basename(sys.argv[0])
+freq21cm = 1420405751.7667 / 1e6 # [MHz]
+
+
+def z2freq(redshifts, print_=False):
+ redshifts = np.asarray(redshifts)
+ freqs = freq21cm / (redshifts + 1.0)
+ if print_:
+ print("# redshift frequency[MHz]")
+ for z, f in zip(redshifts, freqs):
+ print("%.4f %.2f" % (z, f))
+ return freqs
+
+
+def freq2z(freqs, print_=False):
+ freqs = np.asarray(freqs)
+ redshifts = freq21cm / freqs - 1.0
+ if print_:
+ print("# frequency[MHz] redshift")
+ for f, z in zip(freqs, redshifts):
+ print("%.2f %.4f" % (f, z))
+ return redshifts
+
+
+def parse_inputs(inputs):
+ values = []
+ for inp in inputs:
+ try:
+ v = float(inp)
+ values += [v]
+ except ValueError:
+ begin, step, stop = inp.split(":")
+ begin, step, stop = float(begin), float(step), float(stop)
+ v = np.arange(start=begin, stop=stop+step, step=step)
+ values += list(v)
+ return values
+
+
+def main():
+ if prog == "z2freq.py":
+ description = "Convert redshifts to observed 21 cm frequencies"
+ parser = argparse.ArgumentParser(description=description)
+ parser.add_argument("inputs", nargs="+",
+ help="input redshifts: <z1> <begin:step:stop>")
+ args = parser.parse_args()
+ redshifts = parse_inputs(args.inputs)
+ z2freq(redshifts, print_=True)
+ elif prog == "freq2z.py":
+ description = "Convert observed 21 cm frequencies to redshifts"
+ parser = argparse.ArgumentParser(description=description)
+ parser.add_argument("inputs", nargs="+",
+ help="input frequencies [MHz]: <freq1> " +
+ "<begin:step:stop>")
+ args = parser.parse_args()
+ freqs = parse_inputs(args.inputs)
+ freq2z(freqs, print_=True)
+ else:
+ raise RuntimeError("unknown program name: %s" % prog)
+
+
+if __name__ == "__main__":
+ main()