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Choice between vector::resize() and vector::reserve()
... the only effect.
So it depends on what you want. If you want an array of 1000 default items, use resize(). If you want an array to which you expect to insert 1000 items and want to avoid a couple of allocations, use reserve().
EDIT: Blastfurnace's comment made me read the question again and reali...
Group by multiple columns in dplyr, using string vector input
...ike so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data...
How to center a WPF app on screen?
...
146
Put this in your window constructor
WindowStartupLocation = System.Windows.WindowStartupLocat...
How to find out which view is focused?
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113
Call getCurrentFocus() on the Activity.
...
Named Branches vs Multiple Repositories
...
129
The biggest difference is how the branch names are recorded in the history. With named branche...
What's best SQL datatype for storing JSON string?
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199
Certainly NOT:
TEXT, NTEXT: those types are deprecated as of SQL Server 2005 and should not ...
Run Cron job every N minutes plus offset
...-59/20 * * * *
Explanation
An * in the minute field is the same as 0-59/1 where 0-59 is the range and 1 is the step. The command will run at the first minute in the range (0), then at all successive minutes that are distant from the first by step (1), until the last (59).
Which is why */20 * * *...
How do I increase the number of displayed lines of a Java stack trace dump?
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122
You don't need to; that information is present elsewhere in the stack trace. From the docs of ...
How to do this using jQuery - document.getElementById(“selectlist”).value
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150
$('#selectlist').val();
...