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Relative frequencies / proportions with dplyr
...se(n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
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What is the best way to auto-generate INSERT statements for a SQL Server table?
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1055
Microsoft should advertise this functionality of SSMS 2008. The feature you are looking for i...
Minimum and maximum date
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179
From the spec, §15.9.1.1:
A Date object contains a Number indicating a particular instant in...
Extracting numbers from vectors of strings
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11 Answers
11
Active
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How to perform element-wise multiplication of two lists?
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14 Answers
14
Active
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leading zeros in rails
...min , both integers in my application. For hr field, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the min field if the user enter "0" it should put in as "00".
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Cleaning `Inf` values from an R dataframe
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121
Option 1
Use the fact that a data.frame is a list of columns, then use do.call to recreate a ...
How to use the 'sweep' function
...nd use in the operation defined by FUN.
For instance, if you want to add 1 to the 1st row, 2 to the 2nd, etc. of the matrix you defined, you will do:
sweep (M, 1, c(1: 4), "+")
I frankly did not understand the definition in the R documentation either, I just learned by looking up examples.
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What are the most common font-sizes for H1-H6 tags [closed]
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215
It would depend on the browser's default stylesheet. You can view an (unofficial) table of CSS2...