Matplotlib bar chart don't plot x values that are 0

Hi I have a data frame as follows:

              b         c         d         e         f         g

a
-2.447948 0.170758 1.246046 -1.452076 1.248984 -0.010419 0.980928
0.038355 0.106015 0.173747 0.934379 0.485859 -0.192508 -0.899376
-0.584441 -0.384552 0.187411 -1.109639 1.529889 -0.059522 0.319147
1.883600 1.211055 1.434066 0.456128 0.456872 -0.575694 -0.741435
0.351659 1.230753 2.026344 0.303135 2.356994 -0.818239 0.346594
0.665147 -0.449289 0.607148 0.584124 0.007701 -1.663303 -0.127717
-1.539684 -0.356195 -0.986359 1.292305 0.675561 0.279108 -1.561347
1.436973 1.787788 1.444885 -0.359050 1.069496 0.517877 -1.133649
-0.317525 -1.101251 -0.146702 0.890189 1.323071 2.246965 0.706875
1.982059 0.144313 -0.014548 -0.300521 -0.583273 0.424427 -0.329592

index = a, column = col1, col2, col3, values = 10, 12, 15 etc.

I created a for loop to plot a bar chart for each individual product with x-values = columns, y-values = column value.

The code is as follows:

for i in df:
   fig, ax = plt.subplots()
   ax.set_title(i)
   ax.set_ylabel("string")
   plt.tight_layout()    
   df[i].plot.bar(ax=ax)

This successfully creates a bar chart for each group in index a. The problem is columns are still plotted that have 0 values. Is there anyway these columns can be dropped or masked so that each chart only contains x values that have y vales > 0?

I appreciate your help.

Thank you