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Directed grid search: Monochromatic source
Search for a monochromatic (no spindown) signal using a parameter space grid (i.e. no MCMC).
8 import pyfstat
9 import numpy as np
10 import matplotlib.pyplot as plt
11 import os
12
13 label = "PyFstat_example_grid_search_F0"
14 outdir = os.path.join("PyFstat_example_data", label)
15
16 # Properties of the GW data
17 sqrtS = "1e-23"
18 IFOs = "H1"
19 # IFOs = "H1,L1"
20 sqrtSX = ",".join(np.repeat(sqrtS, len(IFOs.split(","))))
21 tstart = 1000000000
22 duration = 100 * 86400
23 tend = tstart + duration
24 tref = 0.5 * (tstart + tend)
25
26 # parameters for injected signals
27 depth = 70
28 inj = {
29 "tref": tref,
30 "F0": 30.0,
31 "F1": 0,
32 "F2": 0,
33 "Alpha": 1.0,
34 "Delta": 1.5,
35 "h0": float(sqrtS) / depth,
36 "cosi": 0.0,
37 }
38
39 data = pyfstat.Writer(
40 label=label,
41 outdir=outdir,
42 tstart=tstart,
43 duration=duration,
44 sqrtSX=sqrtSX,
45 detectors=IFOs,
46 **inj,
47 )
48 data.make_data()
49
50 m = 0.001
51 dF0 = np.sqrt(12 * m) / (np.pi * duration)
52 DeltaF0 = 800 * dF0
53 F0s = [inj["F0"] - DeltaF0 / 2.0, inj["F0"] + DeltaF0 / 2.0, dF0]
54 F1s = [inj["F1"]]
55 F2s = [inj["F2"]]
56 Alphas = [inj["Alpha"]]
57 Deltas = [inj["Delta"]]
58 search = pyfstat.GridSearch(
59 label=label,
60 outdir=outdir,
61 sftfilepattern=os.path.join(outdir, "*" + label + "*sft"),
62 F0s=F0s,
63 F1s=F1s,
64 F2s=F2s,
65 Alphas=Alphas,
66 Deltas=Deltas,
67 tref=tref,
68 minStartTime=tstart,
69 maxStartTime=tend,
70 )
71 search.run()
72
73 # report details of the maximum point
74 max_dict = search.get_max_twoF()
75 print(
76 "max2F={:.4f} from GridSearch, offsets from injection: {:s}.".format(
77 max_dict["twoF"],
78 ", ".join(
79 [
80 "{:.4e} in {:s}".format(max_dict[key] - inj[key], key)
81 for key in max_dict.keys()
82 if not key == "twoF"
83 ]
84 ),
85 )
86 )
87 search.generate_loudest()
88
89 print("Plotting 2F(F0)...")
90 fig, ax = plt.subplots()
91 frequencies = search.data["F0"]
92 twoF = search.data["twoF"]
93 # mismatch = np.sign(x-inj["F0"])*(duration * np.pi * (x - inj["F0"]))**2 / 12.0
94 ax.plot(frequencies, twoF, "k", lw=1)
95 DeltaF = frequencies - inj["F0"]
96 sinc = np.sin(np.pi * DeltaF * duration) / (np.pi * DeltaF * duration)
97 A = np.abs((np.max(twoF) - 4) * sinc**2 + 4)
98 ax.plot(frequencies, A, "-r", lw=1)
99 ax.set_ylabel("$\\widetilde{2\\mathcal{F}}$")
100 ax.set_xlabel("Frequency")
101 ax.set_xlim(F0s[0], F0s[1])
102 dF0 = np.sqrt(12 * 1) / (np.pi * duration)
103 xticks = [inj["F0"] - 10 * dF0, inj["F0"], inj["F0"] + 10 * dF0]
104 ax.set_xticks(xticks)
105 xticklabels = ["$f_0 {-} 10\\Delta f$", "$f_0$", "$f_0 {+} 10\\Delta f$"]
106 ax.set_xticklabels(xticklabels)
107 plt.tight_layout()
108 fig.savefig(os.path.join(outdir, label + "_1D.png"), dpi=300)
Total running time of the script: ( 0 minutes 0.000 seconds)