Figure: single beacon (with Makefile)

figures/beacon/Makefile

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+.PHONY: all dist dist-clean
+
+all: dist
+dist: sine_beacon.pdf ttl_beacon.pdf
+
+sine_beacon.%: src/single_beacon.py
+	$< --periods 2 --with-rates sine $@
+
+ttl_beacon.%: src/single_beacon.py
+	$< --periods 2 --with-rates ttl $@
+
+
+dist-clean:
+	rm -v sine_beacon.*
+	rm -v ttl_beacon.*

figures/beacon/src/single_beacon.py

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+#!/usr/bin/env python3
+
+"""
+Generate a figure showing a beacon (by default 1 period).
+"""
+
+import matplotlib.pyplot as plt
+import numpy as np
+
+def ttl(t, t_start=0, frequency=1, width=0.5):
+    """
+    Generate a TTL with width $width$ and starting at $t_start.
+    """
+
+    return ( (t%frequency) >= t_start) & ( (t%frequency) < t_start + width)
+
+
+def main(beacon_type, N_periods=1, overplot_sampling_rates = False, sampling_rate=5, t_start=0, sampling_offset_in_rate=1/4, ax=None, fig_kwargs={'figsize': (4,2)}):
+
+    t_end = N_periods - t_start
+    N_t = 200
+
+    if ax is None:
+        fig, ax = plt.subplots(1,1, **fig_kwargs)
+
+    time = np.linspace(t_start, t_end, N_t, endpoint=False)
+
+    if beacon_type == 'ttl':
+        sig_func = lambda t: ttl(t, frequency=1)
+    elif beacon_type == 'sine':
+        sig_func = lambda t: np.sin(2*np.pi*t)
+    else:
+        raise ValueError("Unknown beacon_type requested.")
+
+    ax.plot(time, sig_func(time))
+    ax.grid(True)
+
+    if overplot_sampling_rates:
+        sampling_offset = sampling_offset_in_rate * 1/sampling_rate
+
+        sample_time = np.linspace(t_start, t_end, sampling_rate, endpoint=False)
+
+        ax.plot(sample_time, sig_func(sample_time), label='Sampling 1', linestyle='None', marker='x')
+
+        sample_time += sampling_offset
+        ax.plot(sample_time, sig_func(sample_time), label='Sampling 2', linestyle='None', marker='+')
+
+
+        ax.set_ylim(top=1.4)
+        ax.legend(loc="upper center", ncol=2, )
+
+
+    return fig, ax, dict(
+                        sig_func=sig_func,
+                        time=time, 
+                        sample_time=sample_time,
+                        sampling_offset=sampling_offset,
+                    )
+
+
+if __name__ == "__main__":
+    from argparse import ArgumentParser
+    import os.path as path
+
+    parser = ArgumentParser(description=__doc__)
+    parser.add_argument('type', choices=['ttl','sine'])
+    parser.add_argument('--periods', default=1, help='Number of periods to show', type=int)
+    parser.add_argument('--with-rates', action='store_true', help='show two samplings with different phase')
+    parser.add_argument("fname", metavar="path/to/figure[/]", nargs="?", help="Location for generated figure, will append __file__ if a directory. If not supplied, figure is shown.")
+
+    args = parser.parse_args()
+
+    if args.fname is not None and path.isdir(args.fname):
+        args.fname = path.join(args.fname, path.splitext(path.basename(__file__))[0] + ".pdf")
+
+    ###
+    fig, _, _ = main(beacon_type=args.type, overplot_sampling_rates=args.with_rates, N_periods=args.periods)
+
+    if args.fname is not None:
+        plt.savefig(args.fname)
+    else:
+        plt.show()
+