dataframe index existence checking

Question

When I execute the following code, it generates the horizontal line (as desired), but only when this location (index position available) is present in my_data (my_data filtered/chosen previously).

plt.axhline(y=my_data.loc[6805], color='green', linestyle='dashed')

I would like to write something like:

If my_data.loc[6805] is not None:
   plt.axhline(y=my_data.loc[6805], color='green', linestyle='dashed')

How can I check if the index position is available or not?

Answer 1

1] Error Exception Handling

• You can achieve this using error exception handling
• If that location does not exist then you will get a KeyError:

• try-except is what you are looking for

   try: mplt.axhline(y=my_data.loc[6805], color='green', linestyle='dashed') except: pass 

2] Check if 6805 is the index [this is only if 6805 is the index]

• Other thing you can do is check in 6805 exist as the index

   if 6805 in my_data.index.tolist(): mplt.axhline(y=my_data.loc[6805], color='green', linestyle='dashed') 

3] Check the number of rows

• You can check if the total number of rows is greater then or equal to 6805

   if my_data.shape[0] >= 6805 : mplt.axhline(y=my_data.loc[6805], color='green', linestyle='dashed')