3d刻度标签无法正确显示

Question

我正在使用mplot3d绘制3d条形图：

import numpy as np
import matplotlib
matplotlib.use("Qt4Agg")
from mpl_toolkits.mplot3d import Axes3D
import matplotlib.pyplot as plt
from matplotlib import cm

result=[[0, 0, 5, 5, 14,40,50],
[0, 1, 8, 9, 20,50,70],
[0, 2, 8, 10, 25,60,80],
[0, 5, 10, 20, 40,75,100]]

result = np.array(result, dtype=np.int)
fig=plt.figure()
fig.set_size_inches(6, 4)
ax1=fig.add_subplot(111, projection='3d')
ax1.view_init(25, 280)

matplotlib.rcParams.update({'font.size': 12})
matplotlib.rcParams['font.weight']='normal'

xlabels = np.array(["Count1", "Count3","Count5", "Count6","Count7","Count8","Count9"])
xpos = np.arange(xlabels.shape[0])
ylabels = np.array(["5%","10%","20%","100%"])
ypos = np.arange(ylabels.shape[0])

xposM, yposM = np.meshgrid(xpos, ypos, copy=False)

zpos=result
zpos = zpos.ravel()

dx=0.75
dy=0.5
dz=zpos

ax1.w_xaxis.set_ticks(xpos + dx/2.)
ax1.w_xaxis.set_ticklabels(xlabels)

ax1.w_yaxis.set_ticks(ypos + dy/2)
ax1.set_yticklabels(ylabels)

ax1.w_zaxis.set_ticklabels(["","20%","40%","60%","80%","100%"])

colors = ['b','b','b','b','b','b','b','r','r','r','r','r','r','r','y','y','y','y','y','y','y','g','g','g','g','g','g','g']
ax1.bar3d(xposM.ravel(), yposM.ravel(), dz*0, dx, dy, dz, color=colors)
fig.savefig('tmp.tiff', dpi=300)
plt.close()

这就是我得到的：

实际上有两个问题：

1）y刻度标签无法正确显示，它们应该位于刻度线的中间，而是位于刻度线下方。 z刻度标签太靠近z刻度。

2）我想使用字体大小12，dpi应该高于300.我无法缩放x轴，使得x刻度标签很好地适合并且不重叠。我试过将xpos乘以2.然而，刻度标签仍然重叠。