How can I align the y-axis (latitudes) of a map plot and a plot in python - matplotlib-basemap

Question

I'm trying plot two panels in a plot.
The first one (left) is a data with latitude values in its y-axis. The second panel is a map.
I wanna that the latitude values of both panels coinciding, but I don't know how get it.
I have a code like this:
fig_mapa= plt.figure()
'''Mapa'''
ax1=fig_mapa.add_subplot(122)
map = Basemap(llcrnrlon=-90,llcrnrlat=-58.1,urcrnrlon=-32,urcrnrlat=12.6,
resolution='f',projection='merc',lon_0=-58,lat_0=-25, ax=ax1)
map.drawparallels(np.arange(-90,90.,5), labels=[0,1,0,0], linewidth=0.5)
map.drawmeridians(np.arange(-180.,180.,5), labels=[0,0,0,1], linewidth=0.5)
map.readshapefile("./Fases_tectonicas/Shapefiles/Unidades_Fi", 'Unidades_Fi', linewidth=0.1)
#map.warpimage(image='./Geotiffs/NE1_HR_LC_SR_W_DR/NE1_HR_LC_SR_W_DR.tif', zorder=1)
map.drawcoastlines(linewidth=0.5, color='k')
Nombre_Unidad= []
for elemento in map.Unidades_Fi_info:
Nombre_Unidad.append(elemento['NAME'])
for i in range(len(Nombre_Unidad)):
draw=map.Unidades_Fi[i]
poly=Polygon(draw, facecolor=color[Nombre_Unidad[i]],edgecolor='k', alpha=0.5,linewidth=0.1, zorder=2)
plt.gca().add_patch(poly)
'''Gráfico Eventos Compresivos'''
ax2= fig_mapa.add_subplot(121)
ax2.set_ylim(-58.1,12.6)
ax2.set_xlim(120,0)
ax2.set_xlabel('Tiempo [Ma]')
ax2.set_ylabel('Latitud[°]')
ax2.grid()

Answer 1

The simplest way to align two axes is with the sharex or sharey keyword for plt.subplots. However, the coordinates that Basemap shows and the coordinates that it uses for the Axes instance are two different things, so you will have to convert between the two if you want to have understandable ytick labels and some meaningful graph in your second Axes instance. Below I show how you can align the two y-axes, set the yticks properly and transform your data to the data coordinates of your Basemap. I left the creation of the Basemap untouched.
from matplotlib import pyplot as plt
from mpl_toolkits.basemap import Basemap
import numpy as np
##figure with two subplots and shared y-axis
fig,(ax2,ax1) = plt.subplots(nrows=1, ncols=2, sharey='row')
m1 = Basemap(llcrnrlon=-90,llcrnrlat=-58.1,urcrnrlon=-32,urcrnrlat=12.6,
#resolution='f',
projection='merc',lon_0=-58,lat_0=-25, ax=ax1)
m1.drawparallels(np.arange(-90,90.,5), labels=[0,1,0,0], linewidth=0.5)
m1.drawmeridians(np.arange(-180.,180.,5), labels=[0,0,0,1], linewidth=0.5)
m1.drawcoastlines(linewidth=0.5, color='k')
##turning off yticks at basemap
ax1.yaxis.set_ticks_position('none')
##setting yticks:
yticks = np.arange(-55,12.6,5)
##transform yticks:
_,yticks_data = m1(0*yticks,yticks)
ax2.set_yticks(yticks_data)
ax2.set_yticklabels(['{: >3}$^\circ${}'.format(
abs(int(y)), 'N' if y>0 else 'S' if y<0 else ' '
) for y in yticks])
ax2.set_xlim(120,0)
ax2.set_xlabel('Tiempo [Ma]')
ax2.set_ylabel('Latitud[$^\circ$]')
ax2.grid()
#some fake data for testing plotting
yrange = np.linspace(-60,20,100)
temp = (np.sin(10*np.deg2rad(yrange))+1)*50
##transform yrange
_,yrange_data = m1(0*yrange, yrange)
ax2.plot(temp,yrange_data)
plt.show()
The result of the above code looks like this:
Hope this helps.