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CSS3 Transparency + Gradient
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edited Jun 16 '12 at 16:08
umassthrower
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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...
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:
When you group by multiple variables, each summary peels off one level of the grouping. That mak...
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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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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Extracting numbers from vectors of strings
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11 Answers
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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 perform element-wise multiplication of two lists?
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14 Answers
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Difference between decimal, float and double in .NET?
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18 Answers
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How to create a self-signed certificate with OpenSSL
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15 Answers
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