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Remove duplicated rows
...for larger data sets
library(microbenchmark)
library(data.table)
set.seed(123)
DF <- as.data.frame(matrix(sample(1e8, 1e5, replace = TRUE), ncol = 10))
DT <- copy(DF)
setDT(DT)
microbenchmark(unique(DF), unique(DT))
# Unit: microseconds
# expr min lq mean median ...
Variable length (Dynamic) Arrays in Java
...
123
Yes: use ArrayList.
In Java, "normal" arrays are fixed-size. You have to give them a size an...
How do you check that a number is NaN in JavaScript?
...e idea of NaN gets confusing when var value = 0/0; and var value2= String("123 131"); create NaN values and something like this var value3 = "abcd"; is also a NaN value.
– Nick Pineda
Mar 11 '16 at 5:50
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c++11 Return value optimization or move? [duplicate]
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123
All return values are either already moved or optimized out, so there is no need to explicitly...
Match multiline text using regular expression
...ntire string.
Pattern p = Pattern.compile("xyz");
Matcher m = p.matcher("123xyzabc");
System.out.println(m.find()); // true
System.out.println(m.matches()); // false
Matcher m = p.matcher("xyz");
System.out.println(m.matches()); // true
Furthermore, MULTILINE doesn't mean what you think it d...
In Python, how do I index a list with another list?
...
A functional approach:
a = [1,"A", 34, -123, "Hello", 12]
b = [0, 2, 5]
from operator import itemgetter
print(list(itemgetter(*b)(a)))
[1, 34, 12]
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Simple regular expression for a decimal with a precision of 2
...e
deci_num_checker = re.compile(r"""^[0-9]+(\.[0-9]{1,2})?$""")
valid = ["123.12", "2", "56754", "92929292929292.12", "0.21", "3.1"]
invalid = ["12.1232", "2.23332", "e666.76"]
assert len([deci_num_checker.match(x) != None for x in valid]) == len(valid)
assert [deci_num_checker.match(x) == None fo...
fatal: Not a valid object name: 'master'
...newly created (i.e. the primary branch would be something like feature/FOO-123). Those repos would literally not have a master branch at all.
– Thor84no
Aug 14 at 13:56
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实时开发、测试和调试工具 · App Inventor 2 中文网
... 隐私策略和使用条款 技术支持 service@fun123.cn
How to check certificate name and alias in keystore files?
...ven command will yield all aliases containing the pattern 'foo', f.e. foo, 123_FOO, fooBar, etc. For more information man grep.
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