Use this tag for questions related to the pandas.melt or pandas.DataFrame.melt. Be sure to also include the [pandas] tag.
Melt can be used to unpivot a DataFrame from wide to long format.
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Questions tagged [pandas-melt]
102 questions
0
votes
3 answers
Pandas: how to unpivot df correctly?
I have the following dataframe df:
A B Var Value
0 A1 B1 T1name T1
1 A2 B2 T1name T1
2 A1 B1 T2name T2
3 A2 B2 T2name T2
4 A1 B1 T1res 1
5 A2 B2 T1res 1
6 A1 B1 T2res 2
7 A2 B2 T2res 2
I now want to 'half' my dataframe because Var…
Zizzipupp
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2 answers
dataframe how pivot table based on substring of the column
I have a dataframe:
df =
time id ser1 ser2 ... ser20 N0ch0 N1ch0 N2ch0 N0ch1 N1ch1 N2ch1 N0ch2 N1ch2 N2ch2 N0ch3 N1ch3 N2ch3
1 2 4 5 3 8 7 8 5 1 4 6 2 7 9 8 6
And I want to pivot it…
Cranjis
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0
votes
1 answer
Split column into multiple columns when a row starts with a string
I am wanting to split a single column, in a dataframe, into multiple columns whenever a row in the column startswith a specific string. I have a dataframe with a single column like here:
import pandas as pd
lst = ['Group 123 nv-1', 'a, v', 's,b',…
BPhillips
- 7
- 3
0
votes
1 answer
Reshaping pandas df from corsstabulation to long format
I have a dataframe along the lines of the below:
d = {'Country': ['USA', 'France', 'Germany'], 'USA': ['NaN', 2, 5], 'France': [3, 'NaN', 7], 'Germany': [3.5, 4, 'NaN']}
df = pd.DataFrame(data=d)
Country USA France Germany
0 USA NaN 3…
user14237226
- 83
- 4
0
votes
1 answer
list and print it out under each other
I have a problem. I have a list with all amenities of a house. I want to split that list and print it out under each other with pandas melt. I want to use the function melt. I tried that but my result don't looks like what I want.
d = {'hostid': [1,…
Mr. Hankey
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0 answers
Pandas - pandas melt multiindex columns
This is what I received from spreadsheet:
import pandas as pd
import numpy as np
arrays = [['Phase 1','Phase 1','Phase 1','Phase 1','Phase 1','Phase 1','Phase 1','Phase 1','Phase 1'],
['Function A','Function A','Function A','Function…
mgrijo
- 1
- 1
0
votes
0 answers
Long to Wide unpivot with multiple categorical variables in pandas
I have a DataFrame that when simplified looks like the following.
import pandas as pd
report_date_rng = pd.DataFrame(pd.date_range(start='2021-08-01', end='2021-09-14', freq='7D'), columns=['date'])
inp = [{'Store':'A', 'Season':'Summer',…
bkeesey
- 466
- 4
- 12
0
votes
1 answer
Pivot Pandas Python Dataframe
I'm working on this dataset:
# dummy data
import pandas as pd
data = pd.DataFrame({None : ['Company', 'AAA', 'BBB', 'CCC','Company', 'AAA' ],
None : ['Copper', 'Copper', 'Iron', 'Iron', 'Gold', 'Gold'],
…
Luigi
- 59
- 1
- 6
0
votes
1 answer
Numbering for Rows generated through comma separated Pandas DataFrame
I have a Pandas DataFrame as follows:
+----------+---------------+-----------+---------------+
| List No. | List Item No. | Item Name | Issues |
+----------+---------------+-----------+---------------+
| 1 | 1 | A |…
Lopez
- 461
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0
votes
1 answer
groupby and melt Function of COVID-19 URL data with Python
I created a function that read COVID-19 CSV file from a URL, drop some features, and groupby a Country/ Region names. I want this function to use DataFrame.melt to keep 'Country/Region' constant and bring all the dates that existed in rows as a…
Negin Zarbakhsh
- 167
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0
votes
2 answers
Reshape multiples variables with melt with python, Pandas
I have survey date with 5 main variables f1_, f2_, f3_ ,f4_ and f5_ and each f*_ group variable has up to 10 sub groups, ex: f1_1 , f1_2 ,f1_3 ... or f2_1, f2_2, ... f2_10.
I would like to perform a pivot_longer to reshape my dataframe in order to…
DanG
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-1
votes
0 answers
pandas melt gives ValueError if value_name is same as a column name
I have a dataframe that I am using melt that gives me a ValueError in pandas2. Any idea why I get this. This code works fine in older versions though
from pandas import DataFrame
data = DataFrame({'A': ['a1', 'a2', 'a3'], 'B': ['b1', 'b1', 'b2'],…
bhamu
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