I have the following df in pandas:
df:
DATE STOCK DATA1 DATA2 DATA3
01/01/12 ABC 0.40 0.88 0.22
04/01/12 ABC 0.50 0.49 0.13
07/01/12 ABC 0.85 0.36 0.83
10/01/12 ABC 0.28 0.12 0.39
01/01/13 ABC 0.86 0.87 0.58
04/01/13 ABC 0.95 0.39 0.87
07/01/13 ABC 0.60 0.25 0.56
10/01/13 ABC 0.15 0.28 0.69
01/01/11 XYZ 0.94 0.40 0.50
04/01/11 XYZ 0.65 0.19 0.81
07/01/11 XYZ 0.89 0.59 0.69
10/01/11 XYZ 0.12 0.09 0.18
01/01/12 XYZ 0.25 0.94 0.55
04/01/12 XYZ 0.07 0.22 0.67
07/01/12 XYZ 0.46 0.08 0.54
10/01/12 XYZ 0.04 0.03 0.94
...
I want to group by the stocks, sort by date and then for specified columns (in this case DATA1 and DATA3), I want to get the last four items summed (TTM data).
The output would look like this:
DATE STOCK DATA1 DATA2 DATA3 DATA1_TTM DATA3_TTM
01/01/12 ABC 0.40 0.88 0.22 NaN NaN
04/01/12 ABC 0.50 0.49 0.13 NaN NaN
07/01/12 ABC 0.85 0.36 0.83 NaN NaN
10/01/12 ABC 0.28 0.12 0.39 2.03 1.56
01/01/13 ABC 0.86 0.87 0.58 2.49 1.92
04/01/13 ABC 0.95 0.39 0.87 2.94 2.66
07/01/13 ABC 0.60 0.25 0.56 2.69 2.39
10/01/13 ABC 0.15 0.28 0.69 2.55 2.70
01/01/11 XYZ 0.94 0.40 0.50 NaN NaN
04/01/11 XYZ 0.65 0.19 0.81 NaN NaN
07/01/11 XYZ 0.89 0.59 0.69 NaN NaN
10/01/11 XYZ 0.12 0.09 0.18 2.59 2.18
01/01/12 XYZ 0.25 0.94 0.55 1.90 2.23
04/01/12 XYZ 0.07 0.22 0.67 1.33 2.09
07/01/12 XYZ 0.46 0.08 0.54 0.89 1.94
10/01/12 XYZ 0.04 0.03 0.94 0.82 2.70
...
My approach so far has been to sort by date, then group, then iterate through each group and if there are 3 older events then the current event I sum. Also, I want to check to see if the dates fall within 1 year. Can anyone offer a better way in Python? Thank you.
Added: As a clarification for the 1 year part, let's say you take the last four dates and it goes 1/1/1993, 4/1/12, 7/1/12, 10/1/12 -- a data error. I wouldn't want to sum those four. I would want that one to say NaN.
For this I think you can use transform and rolling_sum. Starting from your dataframe, I might do something like:
>>> df["DATE"] = pd.to_datetime(df["DATE"]) # switch to datetime to ease sorting
>>> df = df.sort(["STOCK", "DATE"])
>>> rsum_columns = "DATA1", "DATA3"
>>> grouped = df.groupby("STOCK")[rsum_columns]
>>> new_columns = grouped.transform(lambda x: pd.rolling_sum(x, 4))
>>> df[new_columns.columns + "_TTM"] = new_columns
>>> df
DATE STOCK DATA1 DATA2 DATA3 DATA1_TTM DATA3_TTM
0 2012-01-01 00:00:00 ABC 0.40 0.88 0.22 NaN NaN
1 2012-04-01 00:00:00 ABC 0.50 0.49 0.13 NaN NaN
2 2012-07-01 00:00:00 ABC 0.85 0.36 0.83 NaN NaN
3 2012-10-01 00:00:00 ABC 0.28 0.12 0.39 2.03 1.57
4 2013-01-01 00:00:00 ABC 0.86 0.87 0.58 2.49 1.93
5 2013-04-01 00:00:00 ABC 0.95 0.39 0.87 2.94 2.67
6 2013-07-01 00:00:00 ABC 0.60 0.25 0.56 2.69 2.40
7 2013-10-01 00:00:00 ABC 0.15 0.28 0.69 2.56 2.70
8 2011-01-01 00:00:00 XYZ 0.94 0.40 0.50 NaN NaN
9 2011-04-01 00:00:00 XYZ 0.65 0.19 0.81 NaN NaN
10 2011-07-01 00:00:00 XYZ 0.89 0.59 0.69 NaN NaN
11 2011-10-01 00:00:00 XYZ 0.12 0.09 0.18 2.60 2.18
12 2012-01-01 00:00:00 XYZ 0.25 0.94 0.55 1.91 2.23
13 2012-04-01 00:00:00 XYZ 0.07 0.22 0.67 1.33 2.09
14 2012-07-01 00:00:00 XYZ 0.46 0.08 0.54 0.90 1.94
15 2012-10-01 00:00:00 XYZ 0.04 0.03 0.94 0.82 2.70
[16 rows x 7 columns]
I don't know what you're asking by "Also, I want to check to see if the dates fall within 1 year", so I'll leave that alone.
Related
I have a weather dataset, it gave me many years of data, as below:
Date
rainfallInMon
2009-01-01
0.0
2009-01-02
0.03
2009-01-03
0.05
2009-01-04
0.05
2009-01-05
0.06
...
...
2009-01-29
0.2
2009-01-30
0.21
2009-01-31
0.21
2009-02-01
0.0
2009-02-02
0.0
...
...
I am trying to get the daily rainfall, starting from the end of the month subtracting the previous day. For eg:
Date
rainfallDaily
2009-01-01
0.0
2009-01-02
0.03
2009-01-03
0.02
...
...
2009-01-29
0.01
2009-01-30
0.0
...
...
Thanks for your efforts in advance.
Because there is many years of data need Series.dt.to_period for month periods for distinguish months with years separately:
df['rainfallDaily'] = (df.groupby(df['Date'].dt.to_period('m'))['rainfallInMon']
.diff()
.fillna(0))
Or use Grouper:
df['rainfallDaily'] = (df.groupby(pd.Grouper(freq='M',key='Date'))['rainfallInMon']
.diff()
.fillna(0))
print (df)
Date rainfallInMon rainfallDaily
0 2009-01-01 0.00 0.00
1 2009-01-02 0.03 0.03
2 2009-01-03 0.05 0.02
3 2009-01-04 0.05 0.00
4 2009-01-05 0.06 0.01
5 2009-01-29 0.20 0.14
6 2009-01-30 0.21 0.01
7 2009-01-31 0.21 0.00
8 2009-02-01 0.00 0.00
9 2009-02-02 0.00 0.00
Try:
# Convert to datetime if it's not already the case
df['Date'] = pd.to_datetime(df['Date'])
df['rainfallDaily'] = df.resample('M', on='Date')['rainfallInMon'].diff().fillna(0)
print(df)
# Output
Date rainfallInMon rainfallDaily
0 2009-01-01 0.00 0.00
1 2009-01-02 0.03 0.03
2 2009-01-03 0.05 0.02
3 2009-01-04 0.05 0.00
4 2009-01-05 0.06 0.01
5 2009-01-29 0.20 0.14
6 2009-01-30 0.21 0.01
7 2009-01-31 0.21 0.00
8 2009-02-01 0.00 0.00
9 2009-02-02 0.00 0.00
Supposed we have a df with a sum() value in the below DataFrame, thanks so much for #jezrael 's answer here, now sum value is in the first line, and avg value is the second line, but it's ugly, how to let sum value and avg value in the same column and with index name:Total? Also place it in the first line as below
# Total 27.56 25.04 -1.31
code in pandas is as below:
df.columns=['value_a','value_b','name','up_or_down','difference']
df1 = df[['value_a','value_b']].sum().to_frame().T
df2 = df[['difference']].mean().to_frame().T
df = pd.concat([df1,df2, df], ignore_index=True)
df
value_a value_b name up_or_down difference
project_name
27.56 25.04
-1.31
2021-project11 0.43 0.48 2021-project11 up 0.05
2021-project1 0.62 0.56 2021-project1 down -0.06
2021-project2 0.51 0.47 2021-project2 down -0.04
2021-porject3 0.37 0.34 2021-porject3 down -0.03
2021-porject4 0.64 0.61 2021-porject4 down -0.03
2021-project5 0.32 0.25 2021-project5 down -0.07
2021-project6 0.75 0.81 2021-project6 up 0.06
2021-project7 0.60 0.60 2021-project7 down 0.00
2021-project8 0.85 0.74 2021-project8 down -0.11
2021-project10 0.67 0.67 2021-project10 down 0.00
2021-project9 0.73 0.73 2021-project9 down 0.00
2021-project11 0.54 0.54 2021-project11 down 0.00
2021-project12 0.40 0.40 2021-project12 down 0.00
2021-project13 0.76 0.77 2021-project13 up 0.01
2021-project14 1.16 1.28 2021-project14 up 0.12
2021-project15 1.01 0.94 2021-project15 down -0.07
2021-project16 1.23 1.24 2021-project16 up 0.01
2022-project17 0.40 0.36 2022-project17 down -0.04
2022-project_11 0.40 0.40 2022-project_11 down 0.00
2022-project4 1.01 0.80 2022-project4 down -0.21
2022-project1 0.65 0.67 2022-project1 up 0.02
2022-project2 0.75 0.57 2022-project2 down -0.18
2022-porject3 0.32 0.32 2022-porject3 down 0.00
2022-project18 0.91 0.56 2022-project18 down -0.35
2022-project5 0.84 0.89 2022-project5 up 0.05
2022-project19 0.61 0.48 2022-project19 down -0.13
2022-project6 0.77 0.80 2022-project6 up 0.03
2022-project20 0.63 0.54 2022-project20 down -0.09
2022-project8 0.59 0.55 2022-project8 down -0.04
2022-project21 0.58 0.54 2022-project21 down -0.04
2022-project10 0.76 0.76 2022-project10 down 0.00
2022-project9 0.70 0.71 2022-project9 up 0.01
2022-project22 0.62 0.56 2022-project22 down -0.06
2022-project23 2.03 1.74 2022-project23 down -0.29
2022-project12 0.39 0.39 2022-project12 down 0.00
2022-project24 1.35 1.55 2022-project24 up 0.20
project25 0.45 0.42 project25 down -0.03
project26 0.53 NaN project26 down NaN
project27 0.68 NaN project27 down NaN
Thanks so much for any advice
Use DataFrame.agg with dictionary for aggregate functions:
df.columns=['value_a','value_b','name','up_or_down','difference']
df1 = df.agg({'value_a':'sum', 'value_b':'sum', 'difference':'mean'}).to_frame('Total').T
df = pd.concat([df1,df])
print (df.head())
value_a value_b difference name up_or_down
Total 27.56 25.04 -0.035405 NaN NaN
2021-project11 0.43 0.48 0.050000 2021-project11 up
2021-project1 0.62 0.56 -0.060000 2021-project1 down
2021-project2 0.51 0.47 -0.040000 2021-project2 down
2021-porject3 0.37 0.34 -0.030000 2021-porject3 down
I have created the df_nan below which shows the sum of NaN values from the main df, which, as seen, shows how many are in each specific column.
However, I want to create a new df, which has a column/index of countries, then another with the number of NaN values for the given country.
Country Number of NaN Values
Aruba 4
Finland 3
I feel like I have to use groupby, to create something along the lines of this below, but .isna is not an attribute of the groupby function. Any help would be great, thanks!
df_nan2= df_nan.groupby(['Country']).isna().sum()
Current code
import pandas as pd
import seaborn as sns
import numpy as np
from scipy.stats import spearmanr
# given dataframe df
df = pd.read_csv('countries.csv')
df.drop(columns= ['Population (millions)', 'HDI', 'GDP per Capita','Fish Footprint','Fishing Water',
'Urban Land','Earths Required', 'Countries Required', 'Data Quality'], axis=1, inplace = True)
df_nan= df.isna().sum()
Head of main df
0 Afghanistan Middle East/Central Asia 0.30 0.20 0.08 0.18 0.79 0.24 0.20 0.02 0.50 -0.30
1 Albania Northern/Eastern Europe 0.78 0.22 0.25 0.87 2.21 0.55 0.21 0.29 1.18 -1.03
2 Algeria Africa 0.60 0.16 0.17 1.14 2.12 0.24 0.27 0.03 0.59 -1.53
3 Angola Africa 0.33 0.15 0.12 0.20 0.93 0.20 1.42 0.64 2.55 1.61
4 Antigua and Barbuda Latin America NaN NaN NaN NaN 5.38 NaN NaN NaN 0.94 -4.44
5 Argentina Latin America 0.78 0.79 0.29 1.08 3.14 2.64 1.86 0.66 6.92 3.78
6 Armenia Middle East/Central Asia 0.74 0.18 0.34 0.89 2.23 0.44 0.26 0.10 0.89 -1.35
7 Aruba Latin America NaN NaN NaN NaN 11.88 NaN NaN NaN 0.57 -11.31
8 Australia Asia-Pacific 2.68 0.63 0.89 4.85 9.31 5.42 5.81 2.01 16.57 7.26
9 Austria European Union 0.82 0.27 0.63 4.14 6.06 0.71 0.16 2.04 3.07 -3.00
10 Azerbaijan Middle East/Central Asia 0.66 0.22 0.11 1.25 2.31 0.46 0.20 0.11 0.85 -1.46
11 Bahamas Latin America 0.97 1.05 0.19 4.46 6.84 0.05 0.00 1.18 9.55 2.71
12 Bahrain Middle East/Central Asia 0.52 0.45 0.16 6.19 7.49 0.01 0.00 0.00 0.58 -6.91
13 Bangladesh Asia-Pacific 0.29 0.00 0.08 0.26 0.72 0.25 0.00 0.00 0.38 -0.35
14 Barbados Latin America 0.56 0.24 0.14 3.28 4.48 0.08 0.00 0.02 0.19 -4.29
15 Belarus Northern/Eastern Europe 1.32 0.12 0.91 2.57 5.09 1.52 0.30 1.71 3.64 -1.45
16 Belgium European Union 1.15 0.48 0.99 4.43 7.44 0.56 0.03 0.28 1.19 -6.25
17 Benin Africa 0.49 0.04 0.26 0.51 1.41 0.44 0.04 0.34 0.88 -0.53
18 Bermuda North America NaN NaN NaN NaN 5.77 NaN NaN NaN 0.13 -5.64
19 Bhutan Asia-Pacific 0.50 0.42 3.03 0.63 4.84 0.28 0.34 4.38 5.27 0.43
Nan head
Country 0
Region 0
Cropland Footprint 15
Grazing Footprint 15
Forest Footprint 15
Carbon Footprint 15
Total Ecological Footprint 0
Cropland 15
Grazing Land 15
Forest Land 15
Total Biocapacity 0
Biocapacity Deficit or Reserve 0
dtype: int64
Suppose, you want to get Null count for each Country from "Cropland Footprint" column, then you can use the following code -
Unique_Country = df['Country'].unique()
Col1 = 'Cropland Footprint'
NullCount = []
for i in Unique_Country:
s = df[df['Country']==i][Col1].isnull().sum()
NullCount.append(s)
df2 = pd.DataFrame({'Country': Unique_Country,
'Number of NaN Values': NullCount})
df2 = df2[df2['Number of NaN Values']!=0]
df2
Output -
Country Number of NaN Values
Antigua and Barbuda 1
Aruba 1
Bermuda 1
If you want to get Null Count from another Column then just change the Value of Col1 variable.
I have a dataframe that looks as following:
Type Month Value
A 1 0.29
A 2 0.90
A 3 0.44
A 4 0.43
B 1 0.29
B 2 0.50
B 3 0.14
B 4 0.07
I want to change the dataframe to following format:
Type A B
1 0.29 0.29
2 0.90 0.50
3 0.44 0.14
4 0.43 0.07
Is this possible ?
Use set_index + unstack
df.set_index(['Month', 'Type']).Value.unstack()
Type A B
Month
1 0.29 0.29
2 0.90 0.50
3 0.44 0.14
4 0.43 0.07
To match your exact output
df.set_index(['Month', 'Type']).Value.unstack().rename_axis(None)
Type A B
1 0.29 0.29
2 0.90 0.50
3 0.44 0.14
4 0.43 0.07
Pivot solution:
In [70]: df.pivot(index='Month', columns='Type', values='Value')
Out[70]:
Type A B
Month
1 0.29 0.29
2 0.90 0.50
3 0.44 0.14
4 0.43 0.07
In [71]: df.pivot(index='Month', columns='Type', values='Value').rename_axis(None)
Out[71]:
Type A B
1 0.29 0.29
2 0.90 0.50
3 0.44 0.14
4 0.43 0.07
You're having a case of long format table which you want to transform to a wide format.
This is natively handled in pandas:
df.pivot(index='Month', columns='Type', values='Value')
I have a dataframe df1 where each column represents a time series of returns. I want to create a new dataframe df2 with columns that corresponds to each of the columns in df1 where the column in df2 is defined to be the average of the top 5 most correlated columns in df1.
import pandas as pd
import numpy as np
from string import ascii_letters
np.random.seed([3,1415])
df1 = pd.DataFrame(np.random.randn(100, 10).round(2),
columns=list(ascii_letters[26:36]))
print df1.head()
A B C D E F G H I J
0 -2.13 -1.27 -1.97 -2.26 -0.35 -0.03 0.32 0.35 0.72 0.77
1 -0.61 0.35 -0.35 -0.42 -0.91 -0.14 0.75 -1.50 0.61 0.40
2 -0.96 1.49 -0.35 -1.47 1.06 1.06 0.59 0.30 -0.77 0.83
3 1.49 0.26 -0.90 0.38 -0.52 0.05 0.95 -1.03 0.95 0.73
4 1.24 0.16 -1.34 0.16 1.26 0.78 1.34 -1.64 -0.20 0.13
I expect the head of the resulting dataframe rounded to 2 places to look like:
A B C D E F G H I J
0 -0.78 -0.70 -0.53 -0.45 -0.99 -0.10 -0.47 -0.86 -0.31 -0.64
1 -0.49 -0.11 -0.45 -0.03 -0.04 0.10 -0.26 0.11 -0.06 -0.10
2 0.03 0.13 0.54 0.33 -0.13 0.27 0.22 0.32 0.41 0.27
3 -0.22 0.13 0.19 0.58 0.63 0.24 0.34 0.51 0.32 0.22
4 -0.04 0.31 0.23 0.52 0.43 0.24 0.07 0.31 0.73 0.43
For each column in the correlation matrix, take the six largest and ignore the first one (i.e. 100% correlated with itself). Use a dictionary comprehension to do this for each column.
Use another dictionary comprehension to located this columns in df1 and take their mean. Create a dataframe from the result, and reorder the columns to match those of df1 by appending [df1.columns].
corr = df1.corr()
most_correlated_cols = {col: corr[col].nlargest(6)[1:].index
for col in corr}
df2 = pd.DataFrame({col: df1.loc[:, most_correlated_cols[col]].mean(axis=1)
for col in df1})[df1.columns]
>>> df2.head()
A B C D E F G H I J
0 -0.782 -0.698 -0.526 -0.452 -0.994 -0.102 -0.472 -0.856 -0.310 -0.638
1 -0.486 -0.106 -0.454 -0.032 -0.042 0.100 -0.258 0.108 -0.064 -0.102
2 0.026 0.132 0.544 0.330 -0.130 0.272 0.224 0.320 0.414 0.274
3 -0.224 0.128 0.186 0.582 0.626 0.242 0.344 0.506 0.318 0.224
4 -0.044 0.310 0.230 0.518 0.428 0.238 0.068 0.306 0.734 0.432
%%timeit
corr = df1.corr()
most_correlated_cols = {
col: corr[col].nlargest(6)[1:].index
for col in corr}
df2 = pd.DataFrame({col: df1.loc[:, most_correlated_cols[col]].mean(axis=1)
for col in df1})[df1.columns]
100 loops, best of 3: 10 ms per loop
%%timeit
corr = df1.corr()
df2 = corr.apply(argsort).head(5).apply(lambda x: avg_of(x, df1))
100 loops, best of 3: 16 ms per loop
Setup
import pandas as pd
import numpy as np
from string import ascii_letters
np.random.seed([3,1415])
df1 = pd.DataFrame(np.random.randn(100, 10).round(2),
columns=list(ascii_letters[26:36]))
Solution
corr = df.corr()
# I don't want a securities correlation with itself to be included.
# Because `corr` is symmetrical, I can assume that a series' name will be in its index.
def remove_self(x):
return x.loc[x.index != x.name]
# This builds utilizes `remove_self` then sorts by correlation
# and returns the index.
def argsort(x):
return pd.Series(remove_self(x).sort_values(ascending=False).index)
# This reaches into `df` and gets all columns identified in x
# then takes the mean.
def avg_of(x, df):
return df.loc[:, x].mean(axis=1)
# Putting it all together.
df2 = corr.apply(argsort).head(5).apply(lambda x: avg_of(x, df))
print df2.round(2).head()
A B C D E F G H I J
0 -0.78 -0.70 -0.53 -0.45 -0.99 -0.10 -0.47 -0.86 -0.31 -0.64
1 -0.49 -0.11 -0.45 -0.03 -0.04 0.10 -0.26 0.11 -0.06 -0.10
2 0.03 0.13 0.54 0.33 -0.13 0.27 0.22 0.32 0.41 0.27
3 -0.22 0.13 0.19 0.58 0.63 0.24 0.34 0.51 0.32 0.22
4 -0.04 0.31 0.23 0.52 0.43 0.24 0.07 0.31 0.73 0.43