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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 ...
Associativity of “in” in Python?
...
123
1 in [] in 'a' is evaluated as (1 in []) and ([] in 'a').
Since the first condition (1 in []...
ImportError: No module named apiclient.discovery
...
123
apiclient was the original name of the library.
At some point, it was switched over to be goog...
Get current batchfile directory
...
123
Very simple:
setlocal
cd /d %~dp0
File.exe
...
C99 stdint.h header and MS Visual Studio
...kipedia article, the link authorization is:username: guest, password: guest123
– JPaget
Sep 13 '12 at 23:19
Grand tota...
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
...
How to get function parameter names/values dynamically?
...
123
Below is the code taken from AngularJS which uses the technique for its dependency injection m...
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...
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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