Questions tagged [running-count]
60 questions
242
votes
11 answers
Numbering rows within groups in a data frame
Working with a data frame similar to this:
set.seed(100)
df <- data.frame(cat = c(rep("aaa", 5), rep("bbb", 5), rep("ccc", 5)), val = runif(15))
df <- df[order(df$cat, df$val), ]
df
cat val
1 aaa 0.05638315
2 aaa…

eli-k
- 10,898
- 11
- 40
- 44
78
votes
5 answers
Add a sequential counter column on groups to a pandas dataframe
I feel like there is a better way than this:
import pandas as pd
df = pd.DataFrame(
columns=" index c1 c2 v1 ".split(),
data= [
[ 0, "A", "X", 3, ],
[ 1, "A", "X", 5, ],
[ …

Owen
- 3,063
- 5
- 30
- 26
33
votes
6 answers
Cumulative count of each value
I want to create a cumulative counter of the number of times each value appears.
e.g. say I have the column:
id
1
2
3
2
2
1
2
3
This would become:
id count
1 1
2 1
3 1
2 2
2 3
1 2
2 4
3 …

user1165199
- 6,351
- 13
- 44
- 60
27
votes
5 answers
Add a sequence number to each element in a group using python
I have a dataframe of individuals who each have multiple records. I want to enumerate the record in the sequence for each individual in python. Essentially I would like to create the 'sequence' column in the following table:
patient date …

DKA
- 1,087
- 1
- 9
- 11
23
votes
3 answers
Enumerate each row for each group in a DataFrame
In pandas, how can I add a new column which enumerates rows based on a given grouping?
For instance, assume the following DataFrame:
import pandas as pd
import numpy as np
a_list = ['A', 'B', 'C', 'A', 'A', 'C', 'B', 'B', 'A', 'C']
df =…

Greg Reda
- 1,744
- 2
- 13
- 20
14
votes
4 answers
Pandas cumulative count
I have a data frame like this:
0 04:10 obj1
1 04:10 obj1
2 04:11 obj1
3 04:12 obj2
4 04:12 obj2
5 04:12 obj1
6 04:13 obj2
Wanted to get a cumulative count for all the objects like this:
idx …

jincept
- 279
- 2
- 5
- 16
13
votes
4 answers
Creating a running counting variable in R?
I have a dataset of soccer match results, and I am hoping to learn R by creating a running set of ratings similar to the World Football Elo formula. I am running into trouble with things that seem to be simple in Excel aren't exactly intuitive in…

Matt Barger
- 173
- 1
- 6
11
votes
4 answers
SQL Cumulative Count
I have table with departments. I need to count how many people are within which dept. This is easily done by
SELECT DEPT,
COUNT(*) as 'Total'
FROM SR
GROUP BY DEPT;
Now I need to also do cumulative count as below:
I have found some…

DNac
- 2,663
- 8
- 31
- 54
10
votes
2 answers
Number duplicates sequentially in Pandas DataFrame
I have a Pandas DataFrame that has a column that is basically a foreign key, as below:
Index
f_key
values
0
1
red
1
2
blue
2
1
green
3
2
yellow
4
3
orange
5
1
violet
What I would like is to add a column that labels the…

Rick Berg
- 148
- 2
- 10
8
votes
3 answers
R cumulative sum by condition with reset
I have a vector of numbers in a data.frame such as below.
df <- data.frame(a = c(1,2,3,4,2,3,4,5,8,9,10,1,2,1))
I need to create a new column which gives a running count of entries that are greater than their predecessor. The resulting column…

nsymms
- 115
- 1
- 1
- 7
8
votes
3 answers
Running count based on field in R
I have a data set of this format
User
1
2
3
2
3
1
1
Now I want to add a column saying count which counts the occurrence of the user. I want output in the below format.
User Count
1 1
2 1
3 1
2 2
3 …

Gughan
- 133
- 3
- 8
8
votes
1 answer
How to create subindex efficiently?
I would like to create a subindex for my dataframe based on the index. For example, I have a dataframe like this:
Content Date
ID
Bob birthday 2010.03.01
Bob school 2010.04.01
Tom shopping 2010.02.01
Tom …

Zhen Sun
- 817
- 3
- 13
- 20
8
votes
1 answer
Calculating a running count & running total across customers with SQL
I have the following table (SQL Server 2012):
DID - cust id
GID - order id
AMT - order amt
Gf_Date - order date
SC - order reversal amount
I'm trying to calculate a running count of orders and a running total of sales by customer so that I can…

Chris Howley
- 81
- 1
- 1
- 4
7
votes
2 answers
creating a column which keeps a running count of consecutive values
I am trying to create a column (“consec”) which will keep a running count of consecutive values in another (“binary”) without using loop. This is what the desired outcome would look like:
. binary consec
1 0 0
2 1 1
3 …

MJS
- 1,573
- 3
- 17
- 26
5
votes
1 answer
How to add sequence number for each element in a group using a SQL query without temp tables
My question is quite similar to the one posted in this link - How to add sequence number for groups in a SQL query without temp tables
But, I need to enumerate the occurrence of group. The final output to be like…

user1346265
- 53
- 1
- 1
- 3