Sorting a dataframe by index

Question

I have a dataframe called df that is indexed by date which I am trying to sort oldest date to newest.

I have tried to use both:

df = df.sort(axis=1)

and:

df = df.sort_index(axis=1)

but as you can see from the date order in the following df tail the dates have not been sorted into date order.

                            wood_density  
date                                      
2016-01-27                        5.8821  
2016-01-28                        5.7760  
2015-12-25                           NaN  
2016-01-01                           NaN  
2015-12-26                           NaN

What can I try to resolve this?

axis=1 sorts columns; axis=0 (the default) sorts rows.

Alicia Garcia-Raboso
– Alicia Garcia-Raboso

2016-07-12 12:11:56 +00:00
Commented Jul 12, 2016 at 12:11 — Alicia Garcia-Raboso
– Alicia Garcia-Raboso, Commented Jul 12, 2016 at 12:11

EdChum · Accepted Answer · 2016-07-12 12:10:50Z

2

Use sort_index to sort the index:

In [19]:

df = df.sort_index()
df
Out[19]:
            wood_density
date                    
2015-12-25           NaN
2015-12-26           NaN
2016-01-01           NaN
2016-01-27        5.8821
2016-01-28        5.7760

sort, which is deprecated by sort_values or sort_index sorts on row labels by default axis=0 so it would've worked if you didn't pass this:

In [21]:
df.sort()

Out[21]:
            wood_density
date                    
2015-12-25           NaN
2015-12-26           NaN
2016-01-01           NaN
2016-01-27        5.8821
2016-01-28        5.7760

answered Jul 12, 2016 at 12:10

EdChum

397k204 gold badges836 silver badges583 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Sorting a dataframe by index

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related