I want to make a subplot using the input data
I think this is just a question of passing the spectrogram's "mappable" to plt.colorbar() so that it knows what to make a colourbar for. The tricky thing is that it's a bit buried in an attribute of the spectrogram Axes:
fig, (ax1, ax2, ax3) = plt.subplots(3, sharex=True)
ax1.plot(time, data1[0].data)
ax2.plot(time, data2.data)
spec = data2.spectrogram(axes=ax3, # <-- Assign a name.
show=True,
samp_rate=20,
per_lap=0.5,
wlen=30,
log=True,
cmap='plasma', # <-- Don't use jet :)
clip=(0.05, 0.2),
)
plt.xlabel('Time')
plt.ylabel('Frequency')
# More flexibility with the positioning:
cbar_ax = fig.add_axes([0.2, 0.0, 0.6, 0.05]) # Left, bottom, width, height.
cbar = fig.colorbar(spec.collections[0], # <-- Get the mappable.
cax=cbar_ax,
orientation='horizontal')
cbar.set_label('Colorbar label')
plt.show()
This also shows how to position the colorbar where you want. And I changed your colourmap to plasma because you shouldn't use jet.