I have this dataframe:
lst = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,3,3,3,3,3,3,3,3,3,3,3,3,3]
ser = pd.Series(lst)
df1 = pd.DataFrame(ser, columns=['Quantity'])
When i check unique values from variable quantity i have the following distribution:
df1.groupby(['Quantity'])['Quantity'].count() / sum ( df1['Quantity'])
Quantity
0 0.741935
1 0.338710
2 0.016129
3 0.209677
Name: Quantity, dtype: float64
Because value 2 represents only 0.016 i want to create a new categorical variable that creates "bins" like:
Quantity
0
1-2
3+
How the bins are created is not relevant, the rule of thumb is :
If a number has low representation, it should be aggregated with the other values in a class (bin) .
Other example:
Quantity
0 2662035
1 1200
2 2
Could be converted in :
Quantity
0
1+
You can define the bins the way you want in pandas.cut, by default the right part of the bins is uncluded:
import numpy as np
(pd.cut(df['Quantity'], bins=[-1, 0, 2, np.inf], labels=['0', '1-2', '3+'])
.value_counts()
)
Output:
0 57
1-2 29
3+ 5
Name: Quantity, dtype: int64
combining counts based on a threshold
threshold = 0.05
c = df1['Quantity'].value_counts(sort=False).sort_index()
group = c.div(c.sum()).gt(threshold).cumsum()
(c.reset_index()
.groupby(group)
.agg({'index': lambda x: f'{x.iloc[0]}-{x.iloc[-1]}' if len(x)>1 else str(x.iloc[0]),
'Quantity': 'sum',
})
.set_index('index')
)
Output:
Quantity
index
0 46
1-2 22
3 13
I stumble upon very peculiar problem in Pandas. I have this dataframe
,time,id,X,Y,theta,Vx,Vy,ANGLE_FR,DANGER_RAD,RISK_RAD,TTC_DAN_LOW,TTC_DAN_UP,TTC_STOP,SIM
0,1600349033921610000,0,23.2643889,-7.140948599999999,0,0.020961,-1.1414197,20,0.5,0.9,-1,7,2.0,3
1,1600349033921620000,1,18.5371406,-14.224917,0,-0.0113912,1.443597,20,0.5,0.9,-1,7,2.0,3
2,1600349033921650000,2,19.808648100000006,-6.778450599999998,0,0.037289,-1.0557937,20,0.5,0.9,-1,7,2.0,3
3,1600349033921670000,3,22.1796988,-5.7078115999999985,0,0.2585675,-1.2431861000000002,20,0.5,0.9,-1,7,2.0,3
4,1600349033921670000,4,20.757325,-16.115366,0,-0.2528627,0.7889673,20,0.5,0.9,-1,7,2.0,3
5,1600349033921690000,5,20.9491012,-17.7806833,0,0.5062633,0.9386511,20,0.5,0.9,-1,7,2.0,3
6,1600349033921690000,6,20.6225258,-5.5344404,0,-0.1192678,-0.7889041,20,0.5,0.9,-1,7,2.0,3
7,1600349033921700000,7,21.8077004,-14.736984,0,-0.0295737,1.3084618,20,0.5,0.9,-1,7,2.0,3
8,1600349033954560000,0,23.206789800000006,-7.5171016,0,-0.1727971,-1.1284589,20,0.5,0.9,-1,7,2.0,3
9,1600349033954570000,1,18.555421300000006,-13.7440508,0,0.0548418,1.4426004,20,0.5,0.9,-1,7,2.0,3
10,1600349033954570000,2,19.8409748,-7.126075500000002,0,0.0969802,-1.0428747,20,0.5,0.9,-1,7,2.0,3
11,1600349033954580000,3,22.3263185,-5.9586202,0,0.4398591,-0.752425,20,0.5,0.9,-1,7,2.0,3
12,1600349033954590000,4,20.7154136,-15.842398800000002,0,-0.12573430000000002,0.8189016,20,0.5,0.9,-1,7,2.0,3
13,1600349033954590000,5,21.038901,-17.4111883,0,0.2693992,1.108485,20,0.5,0.9,-1,7,2.0,3
14,1600349033954600000,6,20.612499,-5.810969,0,-0.030080400000000007,-0.8295869,20,0.5,0.9,-1,7,2.0,3
15,1600349033954600000,7,21.7872537,-14.3011986,0,-0.0613401,1.3073578,20,0.5,0.9,-1,7,2.0,3
16,1600349033921610000,0,23.2643889,-7.140948599999999,0,0.020961,-1.1414197,20,0.5,0.9,-1,7,1.5,2
17,1600349033954560000,0,23.206789800000003,-7.5171016,0,-0.1727971,-1.1284589,20,0.5,0.9,-1,7,1.5,2
18,1600349033988110000,0,23.21602,-7.897527,0,0.027693000000000002,-1.1412761999999999,20,0.5,0.9,-1,7,1.5,2
This is input file
Please note that Id always starts at 0 up to 7 and repeat and time column is in sequential step (which implies that previous row should be smaller or equal to current one).
I would like to reorder rows of the dataframe as it is below.
,time,id,X,Y,theta,Vx,Vy,ANGLE_FR,DANGER_RAD,RISK_RAD,TTC_DAN_LOW,TTC_DAN_UP,TTC_STOP,SIM
0,1600349033921610000,0,23.2643889,-7.140948599999999,0,0.020961,-1.1414197,20,0.5,0.9,-1,7,1.0,2
1,1600349033954560000,0,23.206789800000003,-7.5171016,0,-0.1727971,-1.1284589,20,0.5,0.9,-1,7,1.0,2
2,1600349033988110000,0,23.21602,-7.897527,0,0.027693000000000002,-1.1412761999999999,20,0.5,0.9,-1,7,1.0,2
3,1600349033921610000,0,23.2643889,-7.140948599999999,0,0.020961,-1.1414197,20,0.5,0.9,-1,7,1.5,1
4,1600349033954560000,0,23.206789800000003,-7.5171016,0,-0.1727971,-1.1284589,20,0.5,0.9,-1,7,1.5,1
5,1600349033988110000,0,23.21602,-7.897527,0,0.027693000000000002,-1.1412761999999999,20,0.5,0.9,-1,7,1.5,1
6,1600349033921610000,0,23.2643889,-7.140948599999999,0,0.020961,-1.1414197,20,0.5,0.9,-1,7,1.5,2
7,1600349033954560000,0,23.206789800000003,-7.5171016,0,-0.1727971,-1.1284589,20,0.5,0.9,-1,7,1.5,2
8,1600349033988110000,0,23.21602,-7.897527,0,0.027693000000000002,-1.1412761999999999,20,0.5,0.9,-1,7,1.5,2
9,1600349033921610000,0,23.2643889,-7.140948599999999,0,0.020961,-1.1414197,20,0.5,0.9,-1,7,1.5,3
10,1600349033954560000,0,23.206789800000003,-7.5171016,0,-0.1727971,-1.1284589,20,0.5,0.9,-1,7,1.5,3
11,1600349033988110000,0,23.21602,-7.897527,0,0.027693000000000002,-1.1412761999999999,20,0.5,0.9,-1,7,1.5,3
This is the desired result
Please note that I need to reorder dataframe rows based on this columns id, time, ANGLE_FR, DANGER_RAD, RISK_RAD, TTC_DAN_LOW, TTC_DAN_UP, TTC_STOP, SIM.
As you see from the desired result we need to reoder dataframe in that way time column from smallest to largest one this holds true for the rest of columns, id, sim, ANGLE_FR, DANGER_RAD, RISK_RAD, TTC_DAN_LOW, TTC_DAN_UP, TTC_STOP.
I tried to sort by several columns without success. Moreover, I tried to use groupby but I failed.
Would you like to help to solve the problem? Any suggestions are welcome.
P.S.
I have paste dataframe so they can be read easily with clipboard function in order to be easily reproducible.
I am attaching pic as well.
What did you try to sort by several columns?
In [10]: df.sort_values(['id', 'time', 'ANGLE_FR', 'DANGER_RAD', 'RISK_RAD', 'TTC_DAN_LOW', 'TTC_DAN_UP', 'TTC_STOP', 'SIM'])
Out[10]:
Unnamed: 0 time id X Y theta Vx Vy ANGLE_FR DANGER_RAD RISK_RAD TTC_DAN_LOW TTC_DAN_UP TTC_STOP SIM
0 0 1600349033921610000 0 23.2644 -7.1409 0 0.0210 -1.1414 20 0.5 0.9 -1 7 2 3
8 8 1600349033954560000 0 23.2068 -7.5171 0 -0.1728 -1.1285 20 0.5 0.9 -1 7 2 3
1 1 1600349033921620000 1 18.5371 -14.2249 0 -0.0114 1.4436 20 0.5 0.9 -1 7 2 3
9 9 1600349033954570000 1 18.5554 -13.7441 0 0.0548 1.4426 20 0.5 0.9 -1 7 2 3
2 2 1600349033921650000 2 19.8086 -6.7785 0 0.0373 -1.0558 20 0.5 0.9 -1 7 2 3
How about this:
groupby_cols = ['ANGLE_FR', 'DANGER_RAD', 'RISK_RAD', 'TTC_DAN_LOW', 'TTC_DAN_UP', 'TTC_STOP, SIM']
df = df.groupby(groupby_cols).reset_index()
I have a dataframe, something like:
foo bar qux
0 a 1 3.14
1 b 3 2.72
2 c 2 1.62
3 d 9 1.41
4 e 3 0.58
and I would like to add a 'total' row to the end of dataframe:
foo bar qux
0 a 1 3.14
1 b 3 2.72
2 c 2 1.62
3 d 9 1.41
4 e 3 0.58
5 total 18 9.47
I've tried to use the sum command but I end up with a Series, which although I can convert back to a Dataframe, doesn't maintain the data types:
tot_row = pd.DataFrame(df.sum()).T
tot_row['foo'] = 'tot'
tot_row.dtypes:
foo object
bar object
qux object
I would like to maintain the data types from the original data frame as I need to apply other operations to the total row, something like:
baz = 2*tot_row['qux'] + 3*tot_row['bar']
Update June 2022
pd.append is now deprecated. You could use pd.concat instead but it's probably easier to use df.loc['Total'] = df.sum(numeric_only=True), as Kevin Zhu commented. Or, better still, don't modify the data frame in place and keep your data separate from your summary statistics!
Append a totals row with
df.append(df.sum(numeric_only=True), ignore_index=True)
The conversion is necessary only if you have a column of strings or objects.
It's a bit of a fragile solution so I'd recommend sticking to operations on the dataframe, though. eg.
baz = 2*df['qux'].sum() + 3*df['bar'].sum()
df.loc["Total"] = df.sum()
works for me and I find it easier to remember. Am I missing something?
Probably wasn't possible in earlier versions.
I'd actually like to add the total row only temporarily though.
Adding it permanently is good for display but makes it a hassle in further calculations.
Just found
df.append(df.sum().rename('Total'))
This prints what I want in a Jupyter notebook and appears to leave the df itself untouched.
New Method
To get both row and column total:
import numpy as np
import pandas as pd
df = pd.DataFrame({'a': [10,20],'b':[100,200],'c': ['a','b']})
df.loc['Column_Total']= df.sum(numeric_only=True, axis=0)
df.loc[:,'Row_Total'] = df.sum(numeric_only=True, axis=1)
print(df)
a b c Row_Total
0 10.0 100.0 a 110.0
1 20.0 200.0 b 220.0
Column_Total 30.0 300.0 NaN 330.0
Use DataFrame.pivot_table with margins=True:
import pandas as pd
data = [('a',1,3.14),('b',3,2.72),('c',2,1.62),('d',9,1.41),('e',3,.58)]
df = pd.DataFrame(data, columns=('foo', 'bar', 'qux'))
Original df:
foo bar qux
0 a 1 3.14
1 b 3 2.72
2 c 2 1.62
3 d 9 1.41
4 e 3 0.58
Since pivot_table requires some sort of grouping (without the index argument, it'll raise a ValueError: No group keys passed!), and your original index is vacuous, we'll use the foo column:
df.pivot_table(index='foo',
margins=True,
margins_name='total', # defaults to 'All'
aggfunc=sum)
VoilĂ !
bar qux
foo
a 1 3.14
b 3 2.72
c 2 1.62
d 9 1.41
e 3 0.58
total 18 9.47
Alternative way (verified on Pandas 0.18.1):
import numpy as np
total = df.apply(np.sum)
total['foo'] = 'tot'
df.append(pd.DataFrame(total.values, index=total.keys()).T, ignore_index=True)
Result:
foo bar qux
0 a 1 3.14
1 b 3 2.72
2 c 2 1.62
3 d 9 1.41
4 e 3 0.58
5 tot 18 9.47
Building on JMZ answer
df.append(df.sum(numeric_only=True), ignore_index=True)
if you want to continue using your current index you can name the sum series using .rename() as follows:
df.append(df.sum().rename('Total'))
This will add a row at the bottom of the table.
This is the way that I do it, by transposing and using the assign method in combination with a lambda function. It makes it simple for me.
df.T.assign(GrandTotal = lambda x: x.sum(axis=1)).T
Building on answer from Matthias Kauer.
To add row total:
df.loc["Row_Total"] = df.sum()
To add column total,
df.loc[:,"Column_Total"] = df.sum(axis=1)
New method [September 2022]
TL;DR:
Just use
df.style.concat(df.agg(['sum']).style)
for a solution that won't change you dataframe, works even if you have an "sum" in your index, and can be styled!
Explanation
In pandas 1.5.0, a new method named .style.concat() gives you the ability to display several dataframes together. This is a good way to show the total (or any other statistics), because it is not changing the original dataframe, and works even if you have an index named "sum" in your original dataframe.
For example:
import pandas as pd
df = pd.DataFrame([[1, 2, 3], [4, 5, 6]], columns=['A', 'B', 'C'])
df.style.concat(df.agg(['sum']).style)
and it will return a formatted table that is visible in jupyter as this:
Styling
with a little longer code, you can even make the last row look different:
df.style.concat(
df.agg(['sum']).style
.set_properties(**{'background-color': 'yellow'})
)
to get:
see other ways to style (such as bold font, or table lines) in the docs
Following helped for me to add a column total and row total to a dataframe.
Assume dft1 is your original dataframe... now add a column total and row total with the following steps.
from io import StringIO
import pandas as pd
#create dataframe string
dfstr = StringIO(u"""
a;b;c
1;1;1
2;2;2
3;3;3
4;4;4
5;5;5
""")
#create dataframe dft1 from string
dft1 = pd.read_csv(dfstr, sep=";")
## add a column total to dft1
dft1['Total'] = dft1.sum(axis=1)
## add a row total to dft1 with the following steps
sum_row = dft1.sum(axis=0) #get sum_row first
dft1_sum=pd.DataFrame(data=sum_row).T #change it to a dataframe
dft1_sum=dft1_sum.reindex(columns=dft1.columns) #line up the col index to dft1
dft1_sum.index = ['row_total'] #change row index to row_total
dft1.append(dft1_sum) # append the row to dft1
Actually all proposed solutions render the original DataFrame unusable for any further analysis and can invalidate following computations, which will be easy to overlook and could lead to false results.
This is because you add a row to the data, which Pandas cannot differentiate from an additional row of data.
Example:
import pandas as pd
data = [1, 5, 6, 8, 9]
df = pd.DataFrame(data)
df
df.describe()
yields
0
0
1
1
5
2
6
3
8
4
9
0
count
5
mean
5.8
std
3.11448
min
1
25%
5
50%
6
75%
8
max
9
After
df.loc['Totals']= df.sum(numeric_only=True, axis=0)
the dataframe looks like this
0
0
1
1
5
2
6
3
8
4
9
Totals
29
This looks nice, but the new row is treated as if it was an additional data item, so df.describe will produce false results:
0
count
6
mean
9.66667
std
9.87252
min
1
25%
5.25
50%
7
75%
8.75
max
29
So: Watch out! and apply this only after doing all other analyses of the data or work on a copy of the DataFrame!
When the "totals" need to be added to an index column:
totals = pd.DataFrame(df.sum(numeric_only=True)).transpose().set_index(pd.Index({"totals"}))
df.append(totals)
e.g.
(Pdb) df
count min bytes max bytes mean bytes std bytes sum bytes
row_0 837200 67412.0 368733992.0 2.518989e+07 5.122836e+07 2.108898e+13
row_1 299000 85380.0 692782132.0 2.845055e+08 2.026823e+08 8.506713e+13
row_2 837200 67412.0 379484173.0 8.706825e+07 1.071484e+08 7.289354e+13
row_3 239200 85392.0 328063972.0 9.870446e+07 1.016989e+08 2.361011e+13
row_4 59800 67292.0 383487021.0 1.841879e+08 1.567605e+08 1.101444e+13
row_5 717600 112309.0 379483824.0 9.687554e+07 1.103574e+08 6.951789e+13
row_6 119600 664144.0 358486985.0 1.611637e+08 1.171889e+08 1.927518e+13
row_7 478400 67300.0 593141462.0 2.824301e+08 1.446283e+08 1.351146e+14
row_8 358800 215002028.0 327493141.0 2.861329e+08 1.545693e+07 1.026645e+14
row_9 358800 202248016.0 321657935.0 2.684668e+08 1.865470e+07 9.632590e+13
(Pdb) totals = pd.DataFrame(df.sum(numeric_only=True)).transpose()
(Pdb) totals
count min bytes max bytes mean bytes std bytes sum bytes
0 4305600.0 418466685.0 4.132815e+09 1.774725e+09 1.025805e+09 6.365722e+14
(Pdb) totals = pd.DataFrame(df.sum(numeric_only=True)).transpose().set_index(pd.Index({"totals"}))
(Pdb) totals
count min bytes max bytes mean bytes std bytes sum bytes
totals 4305600.0 418466685.0 4.132815e+09 1.774725e+09 1.025805e+09 6.365722e+14
(Pdb) df.append(totals)
count min bytes max bytes mean bytes std bytes sum bytes
row_0 837200.0 67412.0 3.687340e+08 2.518989e+07 5.122836e+07 2.108898e+13
row_1 299000.0 85380.0 6.927821e+08 2.845055e+08 2.026823e+08 8.506713e+13
row_2 837200.0 67412.0 3.794842e+08 8.706825e+07 1.071484e+08 7.289354e+13
row_3 239200.0 85392.0 3.280640e+08 9.870446e+07 1.016989e+08 2.361011e+13
row_4 59800.0 67292.0 3.834870e+08 1.841879e+08 1.567605e+08 1.101444e+13
row_5 717600.0 112309.0 3.794838e+08 9.687554e+07 1.103574e+08 6.951789e+13
row_6 119600.0 664144.0 3.584870e+08 1.611637e+08 1.171889e+08 1.927518e+13
row_7 478400.0 67300.0 5.931415e+08 2.824301e+08 1.446283e+08 1.351146e+14
row_8 358800.0 215002028.0 3.274931e+08 2.861329e+08 1.545693e+07 1.026645e+14
row_9 358800.0 202248016.0 3.216579e+08 2.684668e+08 1.865470e+07 9.632590e+13
totals 4305600.0 418466685.0 4.132815e+09 1.774725e+09 1.025805e+09 6.365722e+14
Since i generally want to do this at the very end as to avoid breaking the integrity of the dataframe (right before printing). I created a summary_rows_cols method which returns a printable dataframe:
def summary_rows_cols(df: pd.DataFrame,
column_sum: bool = False,
column_avg: bool = False,
column_median: bool = False,
row_sum: bool = False,
row_avg: bool = False,
row_median: bool = False
) -> pd.DataFrame:
ret = df.copy()
if column_sum: ret.loc['Sum'] = df.sum(numeric_only=True, axis=0)
if column_avg: ret.loc['Avg'] = df.mean(numeric_only=True, axis=0)
if column_median: ret.loc['Median'] = df.median(numeric_only=True, axis=0)
if row_sum: ret.loc[:, 'Sum'] = df.sum(numeric_only=True, axis=1)
if row_median: ret.loc[:, 'Avg'] = df.mean(numeric_only=True, axis=1)
if row_avg: ret.loc[:, 'Median'] = df.median(numeric_only=True, axis=1)
ret.fillna('-', inplace=True)
return ret
This allows me to enter a generic (numeric) df and get a summarized output such as:
a b c Sum Median
0 1 4 7 12 4
1 2 5 8 15 5
2 3 6 9 18 6
Sum 6 15 24 - -
from:
data = {
'a': [1, 2, 3],
'b': [4, 5, 6],
'c': [7, 8, 9]
}
df = pd.DataFrame(data)
printable = summary_rows_cols(df, row_sum=True, column_sum=True, row_median=True)