matplotlib align twinx tick marks

Question

Is it possible to make a plot with two independent y-axes such that the tick marks align?

Below is an example of half of the solution. I\'ve doubled the y-axis using

Answer 1

I know this is old, but this might help some people in the future.

I made a function based on the solution above that makes sure that the labels don't end up to be something with a lot of decimals:

def calculate_ticks(ax, ticks, round_to=0.1, center=False):
    upperbound = np.ceil(ax.get_ybound()[1]/round_to)
    lowerbound = np.floor(ax.get_ybound()[0]/round_to)
    dy = upperbound - lowerbound
    fit = np.floor(dy/(ticks - 1)) + 1
    dy_new = (ticks - 1)*fit
    if center:
        offset = np.floor((dy_new - dy)/2)
        lowerbound = lowerbound - offset
    values = np.linspace(lowerbound, lowerbound + dy_new, ticks)
    return values*round_to

Which is used the following way:

ax1.set_yticks(calculate_ticks(ax1, 10))
ax2.set_yticks(calculate_ticks(ax2, 10))

Output: