如何迭代 matplotlib 子图中的轴

Question

I'm trying to add a title for 5x2 subplots using matplotlib and the code I wrote is as follows:

fig, axs = plt.subplots(5, 2, figsize=(2*len(cols)+1, 2*len(rows)+1))
for i, ax in axs.flat:

    # print(sum_cols_level[i]) 
      ax.set_title(cols_level[i])

When I run this getting this error

TypeError: cannot unpack non-iterable AxesSubplot object

cols_level is a list containing list of numbers [1,2,3,4.. etc]

I also tried

for i, ax in enumerate(axs.flat):

and got this error;

IndexError: index 9 is out of bounds for axis 0 with size 9

I really appreciate somebody can explain how ax is working and why I'm getting those errors!

Answer 1

The proper solution really depends on what cols_level is. Still, the problem seems to be that you are trying to unzip a 1D numpy flatiter as it was 2D. Forgot to use enumerate ?

fig, axs = plt.subplots(2, 2, figsize=(6,8))
cols_level = [f'ax_{i}' for i in range(len(axs.flat))]
for i, ax in enumerate(axs.flat):
      ax.set_title(cols_level[i])