Equal

Description

Equal compares two aligned input streams element-wise and outputs 1.0 where a == b and 0.0 otherwise.

NaN handling: if either input is NaN at step t, the output is NaN (NaN is not equal to anything, including itself, by IEEE 754).

Parameters: Equal takes no parameters.

Examples

Usage example

import numpy as np
import plotly.graph_objects as go
from plotly.subplots import make_subplots
from screamer import Equal

np.random.seed(0)
# a discrete signal that repeatedly revisits whole-number levels
t = np.linspace(0, 6 * np.pi, 200)
x = np.round(3 + 2 * np.sin(t) + np.random.normal(0, 0.3, size=200))
threshold = np.full_like(x, 3.0)        # a constant level, as a stream
mask = Equal()(x, threshold)            # 1.0 where x == 3.0, else 0.0

fig = make_subplots(rows=2, cols=1, shared_xaxes=True,
                    row_heights=[0.65, 0.35], vertical_spacing=0.08)
fig.add_trace(go.Scatter(y=x, mode="lines", name="x"), row=1, col=1)
fig.add_trace(go.Scatter(y=threshold, mode="lines", name="level = 3.0",
                         line=dict(dash="dash")), row=1, col=1)
fig.add_trace(go.Scatter(y=mask, mode="lines", name="x == level",
                         line=dict(color="red", shape="hv")), row=2, col=1)
fig.update_layout(title="Exactly on a level (Equal)",
                  margin=dict(l=20, r=20, t=60, b=20),
                  legend=dict(orientation="h", yanchor="bottom", y=1.02, xanchor="right", x=1))
fig.update_yaxes(title_text="signal", row=1, col=1)
fig.update_yaxes(title_text="mask (0/1)", range=[-0.1, 1.1], row=2, col=1)
fig.show()