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MySQL remove all whitespaces from the entire column
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203
To replace all spaces :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, ' ', '')
To remov...
map vs. hash_map in C++
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134
They are implemented in very different ways.
hash_map (unordered_map in TR1 and Boost; use tho...
How do negated patterns work in .gitignore?
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3 Answers
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How to succinctly write a formula with many variables from a data frame?
... the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d)
You can also do things like this, to use all variables but one (in this case x3 is excluded):
mod <- lm(y ~ . - x3, data = d)
Technically, . means all ...
AngularJS - wait for multiple resource queries to complete
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Converting between datetime, Timestamp and datetime64
...tetime.utcnow()
>>> dt
datetime.datetime(2012, 12, 4, 19, 51, 25, 362455)
>>> dt64 = np.datetime64(dt)
>>> ts = (dt64 - np.datetime64('1970-01-01T00:00:00Z')) / np.timedelta64(1, 's')
>>> ts
1354650685.3624549
>>> datetime.utcfromtimestamp(ts)
datetime.da...
python: how to identify if a variable is an array or a scalar
...o make a call to this function with a scalar 50 or an array [0, 10, 20, 30] . How can I identify within the function, what the length of NBins is? or said differently, if it is a scalar or a vector?
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Base64 Decoding in iOS 7+
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439
Swift 3+
let plainString = "foo"
Encoding
let plainData = plainString.data(using: .utf8)
le...
Enable Vim Syntax Highlighting By Default
... system (Arch Linux, and Mac, thanks @totophe), it's in /usr/share/vim/vim73.
On Windows, it's in \Program Files\Vim\vim73.
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