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Convert a row of a data frame to vector
...u have to be careful if your row contains a factor. Here is an example:
df_1 = data.frame(V1 = factor(11:15),
V2 = 21:25)
df_1[1,] %>% as.numeric() # you expect 11 21 but it returns
[1] 1 21
Here is another example (by default data.frame() converts characters to factors)
d...
How to get last items of a list in Python?
...
a negative index will count from the end of the list, so:
num_list[-9:]
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How do you reverse a string in place in JavaScript?
...two symbols: U+006E LATIN SMALL LETTER N and U+0303 COMBINING TILDE).
The order in which surrogate pairs appear cannot be reversed, else the astral symbol won’t show up anymore in the ‘reversed’ string. That’s why you saw those �� marks in the output for the previous example.
Combining...
Can I get the name of the current controller in the view?
... If you have your controller behind a namespace like this: Admin::Orders then controller_name and params[:controller] will be "orders" and "admin/orders" respectively.
– Viktor Fonic
Sep 23 '13 at 8:10
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How to call C from Swift?
... frame = CGRect(x: 10, y: 10, width: 100, height: 100)
import Darwin
for _ in 1..10 {
println(rand() % 100)
}
See Interacting with Objective-C APIs in the docs.
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Get a random boolean in python?
...----------------------------------------------------------------
def create_values(fake):
""""""
print fake.boolean(chance_of_getting_true=50) # True
print fake.random_int(min=0, max=1) # 1
if __name__ == "__main__":
fake = Factory.create()
create_values(fake)
...
Quickest way to convert a base 10 number to any base in .NET?
... digits = (new[] { NullDigit }).Concat(digits);
}
_digitToIndexMap =
digits
.Select((digit, index) => new { digit, index })
.ToDictionary(keySelector: x => x.digit, elementSelector: x => x.index);
_radix =...
What does [].forEach.call() do in JavaScript?
...the empty array to a list of all <a> tags, and for each <a> in-order, you are calling the function provided.
EDIT
Logical Conclusion / Cleanup
Below, there's a link to an article suggesting that we scrap attempts at functional programming, and stick to manual, inline looping, every ti...
How to convert An NSInteger to an int?
...endently of whether you are building for a 32-bit or a 64-bit system.
#if __LP64__ || TARGET_OS_EMBEDDED || TARGET_OS_IPHONE || TARGET_OS_WIN32 || NS_BUILD_32_LIKE_64
typedef long NSInteger;
#else
typedef int NSInteger;
#endif
You can use NSInteger any place you use an int without converting it....
receiver type *** for instance message is a forward declaration
...wered Jan 11 '12 at 6:47
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