Twinned (secondary) y-axis

Overlay two series that live on very different scales on a single Plot1D panel, each with its own y-axis. Enable the right-hand axis with add_right_axis(), then add curves to it with add_line(..., axis="right") — they are scaled and labelled independently of the left axis.

import numpy as np
import anyplotlib as apl

x = np.linspace(0, 10, 400)
signal = np.sin(x)                      # left axis: −1 … 1
temperature = 300 + 350 * np.cos(x / 2)  # right axis: ~ −50 … 650

fig, ax = apl.subplots(1, 1, figsize=(560, 360))
plot = ax.plot(signal, axes=[x], color="#4fc3f7", label="signal")
plot.set_ylabel("Amplitude")

Add the secondary axis

add_right_axis turns on the right-hand y-axis; axis="right" anchors the new curve to it. The left axis stays fixed at −1 … 1 while the right axis auto-scales to the temperature range.

plot.add_right_axis(color="#e05a2b")
plot.add_line(temperature, x_axis=x, color="#e05a2b",
              axis="right", label="temperature")
plot.set_right_ylabel("Temperature (K)")

fig

Pin the secondary range

By default the right axis auto-scales to its lines. Call set_right_ylim() to fix it explicitly (for example to line two datasets up at a shared reference level).

plot.set_right_ylim(0, 700)

fig