<s>
pandas	B-Application
is	O
a	O
software	B-Library
library	I-Library
written	O
for	O
the	O
Python	B-Language
programming	I-Language
language	I-Language
for	O
data	O
manipulation	O
and	O
analysis	B-General_Concept
.	O
</s>
<s>
In	O
particular	O
,	O
it	O
offers	O
data	B-General_Concept
structures	I-General_Concept
and	O
operations	O
for	O
manipulating	O
numerical	O
tables	B-Application
and	O
time	O
series	O
.	O
</s>
<s>
It	O
is	O
free	B-Application
software	I-Application
released	O
under	O
the	O
three-clause	O
BSD	O
license	O
.	O
</s>
<s>
The	O
name	O
is	O
derived	O
from	O
the	O
term	O
"	O
panel	O
data	O
"	O
,	O
an	O
econometrics	O
term	O
for	O
data	B-General_Concept
sets	I-General_Concept
that	O
include	O
observations	O
over	O
multiple	O
time	O
periods	O
for	O
the	O
same	O
individuals	O
.	O
</s>
<s>
Its	O
name	O
is	O
a	O
play	O
on	O
the	O
phrase	O
"	O
Python	B-Language
data	B-General_Concept
analysis	I-General_Concept
"	O
itself	O
.	O
</s>
<s>
Wes	O
McKinney	O
started	O
building	O
what	O
would	O
become	O
pandas	B-Application
at	O
AQR	O
Capital	O
while	O
he	O
was	O
a	O
researcher	O
there	O
from	O
2007	O
to	O
2010	O
.	O
</s>
<s>
DataFrame	O
object	B-Language
for	O
multivariate	O
data	O
manipulation	O
with	O
integrated	O
indexing	O
.	O
</s>
<s>
Tools	O
for	O
reading	O
and	O
writing	O
data	O
between	O
in-memory	O
data	B-General_Concept
structures	I-General_Concept
and	O
different	O
file	O
formats	O
.	O
</s>
<s>
Reshaping	O
and	O
pivoting	O
of	O
data	B-General_Concept
sets	I-General_Concept
.	O
</s>
<s>
Label-based	O
slicing	O
,	O
fancy	O
indexing	O
,	O
and	O
subsetting	O
of	O
large	O
data	B-General_Concept
sets	I-General_Concept
.	O
</s>
<s>
Data	B-General_Concept
structure	I-General_Concept
column	O
insertion	O
and	O
deletion	O
.	O
</s>
<s>
Group	O
by	O
engine	O
allowing	O
split-apply-combine	O
operations	O
on	O
data	B-General_Concept
sets	I-General_Concept
.	O
</s>
<s>
Data	B-General_Concept
set	I-General_Concept
merging	O
and	O
joining	O
.	O
</s>
<s>
Hierarchical	O
axis	O
indexing	O
to	O
work	O
with	O
high-dimensional	O
data	O
in	O
a	O
lower-dimensional	O
data	B-General_Concept
structure	I-General_Concept
.	O
</s>
<s>
Time	O
series-functionality	O
:	O
Date	O
range	O
generation	O
and	O
frequency	O
conversions	O
,	O
moving	O
window	O
statistics	O
,	O
moving	O
window	O
linear	B-General_Concept
regressions	I-General_Concept
,	O
date	O
shifting	O
and	O
lagging	O
.	O
</s>
<s>
The	O
library	O
is	O
highly	O
optimized	O
for	O
performance	O
,	O
with	O
critical	O
code	O
paths	O
written	O
in	O
Cython	B-Application
or	O
C	B-Language
.	O
</s>
<s>
Pandas	B-Application
is	O
mainly	O
used	O
for	O
data	B-General_Concept
analysis	I-General_Concept
and	O
associated	O
manipulation	O
of	O
tabular	O
data	O
in	O
DataFrames	O
.	O
</s>
<s>
Pandas	B-Application
allows	O
importing	O
data	O
from	O
various	O
file	O
formats	O
such	O
as	O
comma-separated	O
values	O
,	O
JSON	B-General_Concept
,	O
Parquet	B-General_Concept
,	O
SQL	B-Language
database	I-Language
tables	B-Application
or	O
queries	O
,	O
and	O
Microsoft	B-Application
Excel	I-Application
.	O
</s>
<s>
Pandas	B-Application
allows	O
various	O
data	O
manipulation	O
operations	O
such	O
as	O
merging	O
,	O
reshaping	O
,	O
selecting	O
,	O
as	O
well	O
as	O
data	O
cleaning	O
,	O
and	O
data	B-General_Concept
wrangling	I-General_Concept
features	O
.	O
</s>
<s>
The	O
development	O
of	O
pandas	B-Application
introduced	O
into	O
Python	B-Language
many	O
comparable	O
features	O
of	O
working	O
with	O
DataFrames	O
that	O
were	O
established	O
in	O
the	O
R	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
The	O
pandas	B-Application
library	O
is	O
built	O
upon	O
another	O
library	O
NumPy	B-Application
,	O
which	O
is	O
oriented	O
to	O
efficiently	O
working	O
with	O
arrays	B-Data_Structure
instead	O
of	O
the	O
features	O
of	O
working	O
on	O
DataFrames	O
.	O
</s>
<s>
Developer	O
Wes	O
McKinney	O
started	O
working	O
on	O
pandas	B-Application
in	O
2008	O
while	O
at	O
AQR	O
Capital	O
Management	O
out	O
of	O
the	O
need	O
for	O
a	O
high	O
performance	O
,	O
flexible	O
tool	O
to	O
perform	O
quantitative	O
analysis	B-General_Concept
on	O
financial	O
data	O
.	O
</s>
<s>
Before	O
leaving	O
AQR	O
he	O
was	O
able	O
to	O
convince	O
management	O
to	O
allow	O
him	O
to	O
open	B-License
source	I-License
the	O
library	O
.	O
</s>
<s>
In	O
2015	O
,	O
pandas	B-Application
signed	O
on	O
as	O
a	O
fiscally	O
sponsored	O
project	O
of	O
NumFOCUS	O
,	O
a	O
501(c )	O
(	O
3	O
)	O
nonprofit	O
charity	O
in	O
the	O
United	O
States	O
.	O
</s>
