Index.get_loc()

key : label

method : {None, ?pad?/?ffill?, ?backfill?/?bfill?, ?nearest?}, optional

• default: exact matches only.
• pad / ffill: find the PREVIOUS index value if no exact match.
• backfill / bfill: use NEXT index value if no exact match
• nearest: use the NEAREST index value if no exact match. Tied distances are broken by preferring the larger index value.

tolerance : optional

Maximum distance from index value for inexact matches. The value of the index at the matching location most satisfy the equation abs(index[loc] - key) <= tolerance.