python資料分析實踐（三）

處理維基百科all time olympic games medals資料集。

import pandas as pd

# 讀取資料，選取第一列作為index，並跳過第一行，以第二行作為我的column name
df = pd.read_csv(
'olympics.csv'
, index_col=
0, skiprows=1)
# 對column進行部分重新命名
for col in df.columns:
if col[:2
]=='01'
:        df.rename(columns=
, inplace=
true
)if col[:2
]=='02'
:        df.rename(columns=
, inplace=
true
)if col[:2
]=='03'
:        df.rename(columns=
, inplace=
true
)if col[:1
]=='№':
df.rename(columns=
, inplace=
true
)names_ids = df.index.
str.split(
'\s\('
)# split the index by '('
df.index = names_ids.
str[0]
# the [0] element is the country name (new index) 
df['id'
]= names_ids.
str[1]
.str[:
3]# the [1] element is the abbreviation or id (take first 3 characters from that)
# 刪除total列
df = df.drop(
'totals'
)df.head(
)

def

answer_zero()
:return df.iloc[
0]

任務二：返回夏季奧運會獲得金牌數最多的國家名

def

answer_one()
:return df.gold.idxmax(
)

任務三：返回夏季金牌數和冬季金牌數之差相對於總金牌數最大的國家名（只考慮在夏季冬季奧運會至少都獲得過1枚金牌的國家）

夏 季金

牌數−冬

季金牌數

總金牌數

\frac

總金牌數夏季

金牌數−

冬季金牌

數​

def

answer_three()
:    df1 = df[
(df.gold >0)
&(df[
'gold.1'
]>0)
]return
abs(
(df1[
'gold.1'
]-df1.gold)
/df1[
'gold.2'])
.idxmax(
)

points

=gold.2×3

+silver.2×2

+bronze.2×1

\text=\text\times 3 + \text\times 2 + \text\times 1

points

=gold.2×3

+silver.2×2

+bronze.2×1

def

answer_four()
:return pd.series(data = df[
'gold.2']*
3+ df[
'silver.2']*
2+ df[
'bronze.2']*
1,name=
'points'
)

import pandas as pd

census_df = pd.read_csv(
'census.csv'
)

def

answer_five()
:return census_df[census_df.stname != census_df.ctyname]
.stname.value_counts(
).idxmax(
)

def

answer_six()
:    census_df1 = census_df[census_df.stname != census_df.ctyname][[
'state'
,'stname'
,'ctyname'
,'census2010pop']]
.set_index(
'state'
)    new_df = pd.dataframe(columns=
['state'
,'stname'
,'ctyname'
,'census2010pop'])
for i in
range(56
):try:
new_df = pd.concat(
[new_df, census_df1.loc[i+1]
.sort_values(by=
'census2010pop'
,ascending=
false
).iloc[:3
].reset_index()]
)except keyerror:
pass
return
list
(new_df.groupby(
['stname'])
.sum()
.census2010pop.sort_values(ascending=
false
).iloc[:3
].index)

def

answer_seven()
:    census_df1 = census_df[census_df.stname != census_df.ctyname][[
'ctyname'
,'popestimate2010'
,'popestimate2011'
,'popestimate2012'
,'popestimate2013'
,'popestimate2014'
,'popestimate2015']]
.set_index(
'ctyname'
)return
(census_df1.
max(axis=1)
-census_df1.
min(axis=1)
).idxmax(
)

def

answer_eight()
:return census_df[
(census_df.region <3)
&(census_df.popestimate2015 > census_df.popestimate2014)
&(census_df.ctyname.
str[:10
]=='washington')]
[['stname'
,'ctyname'
]]

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