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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:
When you group by multiple variables, each summary peels off one level of the grouping. That mak...
“Deprecation warning: moment construction falls back to js Date” when trying to convert RFC2822 date
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317
+50
To get r...
emacs/elisp: What is the hash (pound, number sign, octothorp) symbol used for?
...
101
There is no difference:
(eq 'my-add #'my-add)
yields t
The # can be used in front of a lam...
Java: Difference between the setPreferredSize() and setSize() methods in components
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116
Usage depends on whether the component's parent has a layout manager or not.
setSize() -- use...
Can a recursive function be inline?
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139
First, the inline specification on a function is just a hint. The compiler can (and often doe...
Sort a list of tuples by 2nd item (integer value) [duplicate]
...
Try using the key keyword with sorted().
sorted([('abc', 121),('abc', 231),('abc', 148), ('abc',221)], key=lambda x: x[1])
key should be a function that identifies how to retrieve the comparable element from your data structure. In your case, it is the second element of the tupl...
What is the difference between trie and radix trie data structures?
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121
A radix tree is a compressed version of a trie. In a trie, on each edge you write a single let...
Differences between std::make_unique and std::unique_ptr with new
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145
The motivation behind make_unique is primarily two-fold:
make_unique is safe for creating te...
Persistence unit as RESOURCE_LOCAL or JTA?
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101
JPA implementations have the choice of managing transactions themselves (RESOURCE_LOCAL), or h...