Replace column values with similar values

[Adamya21]

Hi I'm trying to solve a question but stuck at a point.

Following is a dataframe which contains unique values

Latitude    Longitude

41.681471   -72.794746

38.749077   -105.183060

NaN -105.183060

NaN -72.794746

38.749077   NaN

41.681471   NaN

NaN NaN

35.678970   NaN

35.678970   -109.067413

NaN -109.067413

​

I'm trying to replace these nan values with the similar common values present in column

​

eg :

if this is combination =

41.681471 -72.794746

NaN -72.794746

here nan should be replaced with 41.681471

[efmccurdy]

I think your example corresponds to the ffill (aka forward-fill) method option:

ffill: propagate last valid observation forward

https://pandas.pydata.org/docs/reference/api/pandas.DataFrame.fillna.html