I have a big dataset. It's about news reading. I'm trying to clean it. I created a checklist of cities that I want to keep (the set has all the cities). How can I drop the rows based on that checklist? For example, I have a checklist (as a list) that contains all the french cities. How can I drop other cities?
To picture the data frame (I have 1.5m rows btw):
City Age
0 Paris 25-34
1 Lyon 45-54
2 Kiev 35-44
3 Berlin 25-34
4 New York 25-34
5 Paris 65+
6 Toulouse 35-44
7 Nice 55-64
8 Hannover 45-54
9 Lille 35-44
10 Edinburgh 65+
11 Moscow 25-34
You can do this using pandas.Dataframe.isin. This will return boolean values checking whether each element is inside the list x. You can then use the boolean values and take out the subset of the df with rows that return True by doing df[df['City'].isin(x)]. Following is my solution:
import pandas as pd
x = ['Paris' , 'Marseille']
df = pd.DataFrame(data={'City':['Paris', 'London', 'New York', 'Marseille'],
'Age':[1, 2, 3, 4]})
print(df)
df = df[df['City'].isin(x)]
print(df)
Output:
>>> City Age
0 Paris 1
1 London 2
2 New York 3
3 Marseille 4
City Age
0 Paris 1
3 Marseille 4
I'll try my best to explain this as I had trouble phrasing the title. I have two dataframes. What I would like to do is add a column from df1 into df2 between every other column.
For example, df1 looks like this :
Age City
0 34 Sydney
1 30 Toronto
2 31 Mumbai
3 32 Richmond
And after adding in df2 it looks like this:
Name Age Clicks City Country
0 Ali 34 10 Sydney Australia
1 Lori 30 20 Toronto Canada
2 Asher 31 45 Mumbai United States
3 Lylah 32 33 Richmond United States
In terms of code, I wasn't quite sure where to even start.
'''Concatenating the dataframes'''
for i in range len(df2):
pos = i+1
df3 = df2.insert
#df2 = pd.concat([df1, df2], axis=1).sort_index(axis=1)
#df2.columns = np.arange(len(df2.columns))
#print (df2)
I was originally going to run it through a loop, but I wasn't quite sure how to do it. Any help would be appreciated!
You can use itertools.zip_longest. For example:
from itertools import zip_longest
new_columns = [
v
for v in (c for a in zip_longest(df2.columns, df1.columns) for c in a)
if not v is None
]
df_out = pd.concat([df1, df2], axis=1)[new_columns]
print(df_out)
Prints:
Name Age Clicks City Country
0 Ali 34 10 Sydney Australia
1 Lori 30 20 Toronto Canada
2 Asher 31 45 Mumbai United States
3 Lylah 32 33 Richmond United States
I want to split one column from my dataframe into multiple columns, then attach those columns back to my original dataframe and divide my original dataframe based on whether the split columns include a specific string.
I have a dataframe that has a column with values separated by semicolons like below.
import pandas as pd
data = {'ID':['1','2','3','4','5','6','7'],
'Residence':['USA;CA;Los Angeles;Los Angeles', 'USA;MA;Suffolk;Boston', 'Canada;ON','USA;FL;Charlotte', 'NA', 'Canada;QC', 'USA;AZ'],
'Name':['Ann','Betty','Carl','David','Emily','Frank', 'George'],
'Gender':['F','F','M','M','F','M','M']}
df = pd.DataFrame(data)
Then I split the column as below, and separated the split column into two based on whether it contains the string USA or not.
address = df['Residence'].str.split(';',expand=True)
country = address[0] != 'USA'
USA, nonUSA = address[~country], address[country]
Now if you run USA and nonUSA, you'll note that there are extra columns in nonUSA, and also a row with no country information. So I got rid of those NA values.
USA.columns = ['Country', 'State', 'County', 'City']
nonUSA.columns = ['Country', 'State']
nonUSA = nonUSA.dropna(axis=0, subset=[1])
nonUSA = nonUSA[nonUSA.columns[0:2]]
Now I want to attach USA and nonUSA to my original dataframe, so that I will get two dataframes that look like below:
USAdata = pd.DataFrame({'ID':['1','2','4','7'],
'Name':['Ann','Betty','David','George'],
'Gender':['F','F','M','M'],
'Country':['USA','USA','USA','USA'],
'State':['CA','MA','FL','AZ'],
'County':['Los Angeles','Suffolk','Charlotte','None'],
'City':['Los Angeles','Boston','None','None']})
nonUSAdata = pd.DataFrame({'ID':['3','6'],
'Name':['David','Frank'],
'Gender':['M','M'],
'Country':['Canada', 'Canada'],
'State':['ON','QC']})
I'm stuck here though. How can I split my original dataframe into people whose Residence include USA or not, and attach the split columns from Residence ( USA and nonUSA ) back to my original dataframe?
(Also, I just uploaded everything I had so far, but I'm curious if there's a cleaner/smarter way to do this.)
There is unique index in original data and is not changed in next code for both DataFrames, so you can use concat for join together and then add to original by DataFrame.join or concat with axis=1:
address = df['Residence'].str.split(';',expand=True)
country = address[0] != 'USA'
USA, nonUSA = address[~country], address[country]
USA.columns = ['Country', 'State', 'County', 'City']
nonUSA = nonUSA.dropna(axis=0, subset=[1])
nonUSA = nonUSA[nonUSA.columns[0:2]]
#changed order for avoid error
nonUSA.columns = ['Country', 'State']
df = pd.concat([df, pd.concat([USA, nonUSA])], axis=1)
Or:
df = df.join(pd.concat([USA, nonUSA]))
print (df)
ID Residence Name Gender Country State \
0 1 USA;CA;Los Angeles;Los Angeles Ann F USA CA
1 2 USA;MA;Suffolk;Boston Betty F USA MA
2 3 Canada;ON Carl M Canada ON
3 4 USA;FL;Charlotte David M USA FL
4 5 NA Emily F NaN NaN
5 6 Canada;QC Frank M Canada QC
6 7 USA;AZ George M USA AZ
County City
0 Los Angeles Los Angeles
1 Suffolk Boston
2 NaN NaN
3 Charlotte None
4 NaN NaN
5 NaN NaN
6 None None
But it seems it is possible simplify:
c = ['Country', 'State', 'County', 'City']
df[c] = df['Residence'].str.split(';',expand=True)
print (df)
ID Residence Name Gender Country State \
0 1 USA;CA;Los Angeles;Los Angeles Ann F USA CA
1 2 USA;MA;Suffolk;Boston Betty F USA MA
2 3 Canada;ON Carl M Canada ON
3 4 USA;FL;Charlotte David M USA FL
4 5 NA Emily F NA None
5 6 Canada;QC Frank M Canada QC
6 7 USA;AZ George M USA AZ
County City
0 Los Angeles Los Angeles
1 Suffolk Boston
2 None None
3 Charlotte None
4 None None
5 None None
6 None None
I have three dataframes df_Male , df_female , Df_TransGender
sample dataframe df_Male
continent avg_count_country avg_age
Asia 55 5
Africa 65 10
Europe 75 8
df_Female
continent avg_count_country avg_age
Asia 50 7
Africa 60 12
Europe 70 0
df_Transgender
continent avg_count_country avg_age
Asia 30 6
Africa 40 11
America 80 10
Now our stacked bar grap should look like
X axis will contain three ticks Male , Female , Transgender
Y axis will be Total_count--100
And in the Bar avg_age will be stacked
Now I was trying like with pivot table
pivot_df = df.pivot(index='new_Columns', columns='avg_age ', values='Values')
getting confused how to plot this , can anyone please help on how to concatenate three dataframe in one , so that it create Male,Female and Transgener columns
This topic is handeled here: https://pandas.pydata.org/pandas-docs/stable/merging.html
(Please note, that the third continent in df_Transgenderis different to the other dataframes, 'America' instead of 'Europe'; I changed that for the following plot, hoping that this is correct.)
frames = [df_Male, df_Female, df_Transgender]
df = pd.concat(frames, keys=['Male', 'Female', 'Transgender'])
continent avg_count_country avg_age
Male 0 Asia 55 5
1 Africa 65 10
2 Europe 75 8
Female 0 Asia 50 7
1 Africa 60 12
2 Europe 70 0
Transgender 0 Asia 30 6
1 Africa 40 11
2 Europe 80 10
btm = [0, 0, 0]
for name, grp in df.groupby('continent', sort=False):
plt.bar(grp.index.levels[1], grp.avg_age.values, bottom=btm, tick_label=grp.index.levels[0], label=name)
btm = grp.avg_age.values
plt.legend(ncol = 3)
As you commented below that America in the third dataset was no mistake, you can add rows accordingly to each dataframe like this bevor you go on like above:
df_Male.append({'avg_age': 0, 'continent': 'America'}, ignore_index=True)
df_Female.append({'avg_age': 0, 'continent': 'America'}, ignore_index=True)
df_Transgender.append({'avg_age': 0, 'continent': 'Europe'}, ignore_index=True)
I have two dataframes as shown below.
Company Name BOD Position Ethnicity DOB Age Gender Degree ( Specialazation) Remark
0 Big Lots Inc. David J. Campisi Director, President and Chief Executive Offic... American 1956 61 Male Graduate NaN
1 Big Lots Inc. Philip E. Mallott Chairman of the Board American 1958 59 Male MBA, Finace NaN
2 Big Lots Inc. James R. Chambers Independent Director American 1958 59 Male MBA NaN
3 Momentive Performance Materials Inc Mahesh Balakrishnan director Asian 1983 34 Male BA Economics NaN
Company Name Net Sale Gross Profit Remark
0 Big Lots Inc. 5.2B 2.1B NaN
1 Momentive Performance Materials Inc 544M 146m NaN
2 Markel Corporation 5.61B 2.06B NaN
3 Noble Energy, Inc. 3.49B 2.41B NaN
4 Leidos Holding, Inc. 7.04B 852M NaN
I want to create a new dataframe with these two, so that in 2nd dataframe, I have new columns with count of ethinicities from each companies, such as American -2 Mexican -5 and so on, so that later on, i can calculate diversity score.
the variables in the output dataframe is like,
Company Name Net Sale Gross Profit Remark American Mexican German .....
Big Lots Inc. 5.2B 2.1B NaN 2 0 5 ....
First get counts per groups by groupby with size and unstack, last join to second DataFrame:
df1 = pd.DataFrame({'Company Name':list('aabcac'),
'Ethnicity':['American'] * 3 + ['Mexican'] * 3})
df1 = df1.groupby(['Company Name', 'Ethnicity']).size().unstack(fill_value=0)
#slowier alternative
#df1 = pd.crosstab(df1['Company Name'], df1['Ethnicity'])
print (df1)
Ethnicity American Mexican
Company Name
a 2 1
b 1 0
c 0 2
df2 = pd.DataFrame({'Company Name':list('abc')})
print (df2)
Company Name
0 a
1 b
2 c
df3 = df2.join(df1, on=['Company Name'])
print (df3)
Company Name American Mexican
0 a 2 1
1 b 1 0
2 c 0 2
EDIT: You need replace unit by 0 and convert to floats:
print (df)
Name sale
0 A 100M
1 B 200M
2 C 5M
3 D 40M
4 E 10B
5 F 2B
d = {'M': '0'*6, 'B': '0'*9}
df['a'] = df['sale'].replace(d, regex=True).astype(float).sort_values(ascending=False)
print (df)
Name sale a
0 A 100M 1.000000e+08
1 B 200M 2.000000e+08
2 C 5M 5.000000e+06
3 D 40M 4.000000e+07
4 E 10B 1.000000e+10
5 F 2B 2.000000e+09