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Questions - grouping

get top 3 values per row and keep the column index

Consider the following matrix: m <- structure(c(0.00165720273925865, 0.000414300684814661, 0.00126727268296249, 0.0105768527770331, 0.00126727268296249, 0.00155972022518461, 0.00046304194185168,...
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moth

r

sorting

grouping

subset

Votes: 0

Answers: 1

Latest Answer

You can use order to get the indices, and head(x, 3) to get the top 3 values. head(apply(m, 1, function(x) order(x, decreasing = TRUE)), 3) M001_0.6 M002_0.6 M004_0.6 M012_0.6 M013_0.6 [1,] ...
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Ma&#235;l

How to create groups and subgroups in pandas dataframe

I have a pandas dataframe with laboratory tests, and for each sample, I have a few tests. For example, in this synthetic data I have 3 sample each one with 3 test pieces. I need to get the value of a ...
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JCV

python

dataframe

pandas-groupby

grouping

Votes: 0

Answers: 1

Latest Answer

First of all, well done for postig sample data and expected output to this question!! With groupby you don't need to use tx.loc, here your answer: tx.groupby(['Name','ID'])['du'].max() groupby: ma...
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guardian

How Affect Group By to Other Second Join Table

I have some table like this table request_buys | id | invoice | user_id | | -- | ----------------- | ------- | | 3 | 20220405/01104298 | 1 | table traces | id | request_buy_id | stat...
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Edo Sulai

mysql

join

group-by

grouping

Votes: 0

Answers: 2

Latest Answer

Your problem lies with your misuse of the MAX(statuses.nama) expression. Based on your expected output,you intend to get the statuses.nama which matches the MAX(traces.id), NOT the MAX(statuses.nama)...
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blabla_bingo

How to count the number of times a value changes, grouped by two variables in R

I have a dataframe similar to the constructed one below, but much larger. id <- rep(c("a", "b", "c", "d"), each = 3) date <- seq(as.Date("2019-01-27&...
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TRS6

r

grouping

cumsum

Votes: 0

Answers: 0

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