1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
|
import nixio
import docutils
import numpy as np
import matplotlib.pyplot as plt
def create_data(interval=0.001):
time = np.arange(0., 1.0, interval)
freq = 5.
signal = np.sin(time * 2 * np.pi * freq) + np.sin(time * 2 * np.pi * 2 * freq) * 0.4
events = time[(signal > 0.5) & (np.roll(signal, -1) <= 0.5)]
return signal, events
def plot(multi_tag):
event_array = multi_tag.positions
event_times = multi_tag.positions[:]
signal_array = multi_tag.references["signal"]
signal = signal_array[:]
x_axis = signal_array.dimensions[0]
time = x_axis.axis(len(signal))
fig = plt.figure()
fig.set_size_inches(5.5, 2.5)
ax = fig.add_subplot(111)
ax.plot(time, signal, label='voltage', zorder=0)
ax.scatter(event_times, np.ones(event_times.shape) * 0.5, marker=".", s=75, color='red',
label=event_array.name, zorder=1)
ax.set_xlim([0., 1.])
ax.set_ylim([-1.75, 1.75])
ax.set_xticks(np.arange(0, 1.01, 0.25))
ax.set_yticks(np.arange(-1.5, 1.6, 0.5))
ax.set_xlabel(x_axis.label + ((" [" + x_axis.unit + "]") if x_axis.unit else ""))
ax.set_ylabel("%s [%s]" % (signal_array.label, signal_array.unit))
ax.spines["top"].set_visible(False)
ax.spines["right"].set_visible(False)
fig.subplots_adjust(bottom=0.175, left=0.15, right=0.95, top=0.95)
ax.legend(loc=3, frameon=False, ncol=2)
if docutils.is_running_under_pytest():
plt.close()
else:
# fig.savefig("../images/multiple_points.png")
plt.show()
def main():
sampling_interval = 0.001
signal, events = create_data(sampling_interval)
nixfile = nixio.File.open("multiple_points.nix", nixio.FileMode.Overwrite)
block = nixfile.create_block("recording session", "nix.session")
signal_array = block.create_data_array("signal", "nix.sampled", data=signal, label="voltage", unit="mV")
signal_array.append_sampled_dimension(sampling_interval, label="time", unit="s")
event_array = block.create_data_array("threshold crossings", "nix.events.threshold_crossings", data=events, label="time", unit="s")
event_array.append_range_dimension_using_self()
mtag = block.create_multi_tag("event tag", "nix.tag.events", event_array)
mtag.references.append(signal_array)
plot(mtag)
nixfile.close()
if __name__ == "__main__":
main()
|
