Linked Questions
55 questions linked to/from pandas three-way joining multiple dataframes on columns
-1
votes
3
answers
100
views
python - combined 3 data frames, but need to realign data by values in 1 column [duplicate]
I have several data sources that i'm trying to work with - i asked a related question a couple of days ago (click here!
so i have 3 dataframes each with a 'user_id' column that is common across all 3 ...
- 143
1
vote
2
answers
72
views
I have 3 dataframes inside just one. How can I concat them? [duplicate]
I'm really stuck into this. I don't know how to make these 3 dataframes into one because they are inside an array or so. I really need your help.
import numpy as np
import pandas as pd
import ...
- 11
0
votes
1
answer
57
views
Merging Dataframes on Month, Or Unlike Column & Grouping [duplicate]
I have three dataframes I would like where I want to merge or join them based on the month column/field, then group by title.
df1:
Month Year TotalNumberofStreams TitleSortName
9 2018 ...
- 35
0
votes
0
answers
56
views
How can I iterate over pandas dataframes and concatenate on another dataframe [duplicate]
I have a few files that I've read into pandas dataframes that share the same values for the 0 column, but have differing values for the 1 column.
How can I iterate over multiple dataframes, pull out ...
- 691
-2
votes
1
answer
43
views
I have a for loop that generates different pandas dataframes whose values I want to save sequentially [duplicate]
I made a for loop that creates a different pandas dataframe on each iteration. Something like this ->
First iteration:
index
Letter
Value
0
A
1
1
B
2
2
C
3
Second iteration:
index
Letter
Value
0
C
...
- 3
947
votes
8
answers
465k
views
Pandas Merging 101
How can I perform a (INNER| (LEFT|RIGHT|FULL) OUTER) JOIN with pandas?
How do I add NaNs for missing rows after a merge?
How do I get rid of NaNs after merging?
Can I merge on the index?
How do I ...
- 406k
202
votes
13
answers
534k
views
How to merge multiple dataframes
I have different dataframes and need to merge them together based on the date column. If I only had two dataframes, I could use df1.merge(df2, on='date'), to do it with three dataframes, I use df1....
- 2,383
244
votes
7
answers
188k
views
NameError: name 'reduce' is not defined in Python
I'm using Python 3.2. Tried this:
xor = lambda x,y: (x+y)%2
l = reduce(xor, [1,2,3,4])
And got the following error:
l = reduce(xor, [1,2,3,4])
NameError: name 'reduce' is not defined
Tried printing ...
- 50.1k
15
votes
3
answers
50k
views
Finding common elements between multiple dataframe columns
Hope you could help me. I am new to python and pandas, so please bear with me. I am trying to find the common word between three data frames and I am using Jupiter Notebook.
Just for example:
df1=
A
...
- 167
5
votes
2
answers
23k
views
Merging two data frames based on the index column [duplicate]
I have two dataframes, I wanted to merge them into one single dataframe based on the matching row. My dataframe looks like this
DF_1
Set_1 Fax_1 Fax_2
Abc_1 45 76
Abc_2 46 77
Abc_3 47 ...
- 2,090
12
votes
1
answer
19k
views
Several time series to DataFrame
I have problem merging several time series to a common DataFrame. The example code I'm using:
import pandas
import datetime
import numpy as np
start = datetime.datetime(2001, 1, 1)
end = datetime....
- 649
8
votes
2
answers
13k
views
Create all possible combinations of multiple columns in a Pandas DataFrame
Given the below DataFrame,
df = pd.DataFrame({'Student':['Siri','Alexa'], 'Class':['6', '7'], 'Section':['A','B'], 'Teacher':['Ravi','Mark'], 'School':['C','D']})
I would like to return a table with ...
5
votes
3
answers
10k
views
Pandas: merge multiple dataframes and control column names?
I would like to merge nine Pandas dataframes together into a single dataframe, doing a join on two columns, controlling the column names. Is this possible?
I have nine datasets. All of them have the ...
- 66.1k
3
votes
1
answer
8k
views
efficiently merge multiple dataframes in pandas [duplicate]
What is the most efficient way to merge multiple data frames (i.e., more than 2) in pandas? There are a few answers:
pandas joining multiple dataframes on columns
Pandas left outer join multiple ...
- 41
1
vote
2
answers
16k
views
ValueError: Indexes have overlapping values
I should join 2 pandas DataFrames with partially overlapping column names: Col1,Col2. The other columns do not overlap.
I get the following error:
ValueError: Indexes have overlapping values: Index(...
- 2,998