How to adjust space between every second row of su

问题:

I'm hoping to adjust the space between subplots horizontally. Specifically between every second row. I can adjust every row using fig.subplots_adjust(hspace=n). But is it possible to apply this to every 2nd row?

import matplotlib.pyplot as plt

fig, ax = plt.subplots(figsize = (10,10))
plt.style.use('ggplot')
ax.grid(False)

ax1 = plt.subplot2grid((5,2), (0, 0))
ax2 = plt.subplot2grid((5,2), (0, 1))
ax3 = plt.subplot2grid((5,2), (1, 0))  
ax4 = plt.subplot2grid((5,2), (1, 1))
ax5 = plt.subplot2grid((5,2), (2, 0))
ax6 = plt.subplot2grid((5,2), (2, 1)) 
ax7 = plt.subplot2grid((5,2), (3, 0))
ax8 = plt.subplot2grid((5,2), (3, 1))

fig.subplots_adjust(hspace=0.9)

Using the subplots below I'm hoping to add a space between rows 2 and 3 and keep the rest as is.

回答1:

You may interlace two grids such that there is a larger spacing between every second subplot.

To illustrate the concept:

import matplotlib.pyplot as plt
from matplotlib.gridspec import GridSpec

n = 3 # number of double-rows
m = 2 # number of columns

t = 0.9 # 1-t == top space 
b = 0.1 # bottom space      (both in figure coordinates)

msp = 0.1 # minor spacing
sp = 0.5  # major spacing

offs=(1+msp)*(t-b)/(2*n+n*msp+(n-1)*sp) # grid offset
hspace = sp+msp+1 #height space per grid

gso = GridSpec(n,m, bottom=b+offs, top=t, hspace=hspace)
gse = GridSpec(n,m, bottom=b, top=t-offs, hspace=hspace)

fig = plt.figure()
axes = []
for i in range(n*m):
    axes.append(fig.add_subplot(gso[i]))
    axes.append(fig.add_subplot(gse[i]))

plt.show()

回答2:

Without going to tedious low-level hacks like adjusting the position of the axes manually, I would suggest using a grid but just leaving some of the rows blank.

I tried this:

import matplotlib.pyplot as plt

plt.figure(figsize=(10., 10.))

num_rows = 6
num_cols = 2

row_height = 3
space_height = 2

num_sep_rows = lambda x: int((x-1)/2)
grid = (row_height*num_rows + space_height*num_sep_rows(num_rows), num_cols)

ax_list = []

for ind_row in range(num_rows):
    for ind_col in range(num_cols):
        grid_row = row_height*ind_row + space_height*num_sep_rows(ind_row+1)
        grid_col = ind_col

        ax_list += [plt.subplot2grid(grid, (grid_row, grid_col), rowspan=row_height)]

plt.subplots_adjust(bottom=.05, top=.95, hspace=.1)

# plot stuff
ax_list[0].plot([0, 1])
ax_list[1].plot([1, 0])
# ...
ax_list[11].plot([0, 1, 4], c='C2')

which gives this result:

Note that you can change the number of rows; also, you can adjust the size of the blank space compared to the subplots by tweaking the row_height/space_height ratio (both must be integers).