figure: spatial time difference setup

figures/beacon/Makefile

@@ -9,6 +9,9 @@ dist-clean:
 	rm -v sine_beacon.*
 	rm -v ttl_beacon.*
 
+beacon_spatial_time_difference_setup.pdf: src/beacon_spatial_time_difference_setup.py
+	$< $@
+
 sine_beacon.%: src/single_beacon.py
 	$< --periods 2 --with-rates sine $@
 

figures/beacon/src/beacon_spatial_time_difference_setup.py

@@ -0,0 +1,172 @@
+#!/usr/bin/env python3
+
+__doc__ = \
+"""
+Generate a figure showing why a single beacon does
+not arrive at the same time at two antennas.
+"""
+
+import matplotlib.pyplot as plt
+import numpy as np
+import scipy.signal as sig
+
+### Functions
+
+def beacon_time_difference_setup_figure(
+        ax, 
+        loc_trans, loc_antenna1, loc_antenna2,
+        trans_kwargs={}, ant_kwargs={}
+):
+    """
+    """
+    return t, ants 
+
+
+def _annotate_width(
+        ax, name,
+        x1, x2, y1=None, y2=None,
+        text_dx=(0,0),
+        text_kw={}, arrow_kw={}
+):
+    """
+    Annotate a width between two points, with both an arrow between
+    the points, and a text between them.
+
+    Parameters:
+    -----------
+    ax: Axes
+     the Axes to plot on
+    name: str
+     text to put on top of the arrow
+    x1: float or tuple
+     (horizontal) location of the first point
+    x2: float or tuple
+     (horizontal) location of the first point
+    y1: float
+     vertical location of the first point
+    y2: float
+     vertical location of the first point
+
+    """
+    if hasattr(x1, '__len__'):
+        if y1 is None:
+            y1 = x1[1]
+        x1 = x1[0]
+
+    if hasattr(x2, '__len__'):
+        if y2 is None:
+            y2 = x2[1]
+        x2 = x2[0]
+
+    y1 = 0 if y1 is None else y1
+    y2 = y1 if y2 is None else y2
+
+    default_arrow_kw = dict(
+            xy = (x1, y1),
+            xytext = (x2,y2),
+            arrowprops = dict(
+                arrowstyle="<->",
+                shrinkA=False,
+                shrinkB=False
+            ),
+    )
+
+    default_text_kw = dict(
+            va='bottom',
+            ha='center',
+            xy=((x1+x2)/2 + text_dx[0], (y1+y2)/2 + text_dx[1])
+    )
+
+    an1 = ax.annotate("", **{**default_arrow_kw, **arrow_kw})
+    an2 = ax.annotate(name, **{**default_text_kw, **text_kw})
+
+    return [an1, an2]
+
+
+## Main
+def main():
+    """
+    """
+
+    trans_kwargs = {
+            'zorder': 4,
+            }
+    ant_kwargs = {
+            'zorder': 4,
+            }
+    annot_kwargs = {
+            }
+ 
+    trans_loc = [0.2, 0.9]
+    ant1_loc = [0.2, 0.4]
+    ant2_loc = [0.4, 0.2]
+
+    ###########################
+    fig, ax = plt.subplots(1,1,sharex=True, gridspec_kw={'hspace': 0});
+
+    # Overall styling
+    if True:
+        ax.set_aspect('equal')
+        ax.spines['top'].set_visible(False)
+        ax.spines['right'].set_visible(False)
+        ax.spines['bottom'].set_visible(False)
+        ax.spines['left'].set_visible(False)
+
+        #ax.axis('off')
+        ax.set_xticks([])
+        ax.set_xticklabels([])
+        #ax.set_ylim(-0.2, 1.2)
+        #ax.set_xlim(0, 1)
+        #ax.set_ylim(0, 1)
+        ax.set_yticks([])
+        ax.set_yticklabels([])
+
+    # Transmitter
+    t = ax.plot(*trans_loc, '*', **trans_kwargs)
+    ax.annotate('T', xy=trans_loc, ha='right', va='bottom')
+
+    # Antenna
+    ants = []
+    annoti_kwargs = [
+            dict(text_kw=dict(va='center', ha='left')),
+            dict(text_kw=dict(ha='left'))
+            ]
+    for i, loc in enumerate([ant1_loc, ant2_loc], start=1):
+        ants.append(
+            ax.plot(*loc, '*', **ant_kwargs)
+        )
+
+        ## Distance between Antenna and Transmitter
+        default_annot_kwargs = {
+        }
+        _annotate_width(ax, f"$t_{i}$", trans_loc, loc, **{**default_annot_kwargs, **annot_kwargs, **annoti_kwargs[i-1]} )
+
+        if True:
+            ax.annotate(f"$A_{i}$", xy=loc, ha='right', va='top')
+
+    # Distance between two antennas
+    _annotate_width(ax, f"$t_d$", ant1_loc, ant2_loc, text_kw=dict(ha='right', va='top'))
+
+    return fig, 0
+
+
+if __name__ == "__main__":
+    from argparse import ArgumentParser
+    import os.path as path
+
+    parser = ArgumentParser(description=__doc__)
+    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()
+
+    if args.fname is not None:
+        plt.savefig(args.fname)
+    else:
+        plt.show()
+