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C++ Tuple vs Struct
...nchmark code and performance results collected using gcc-4.9.2 and clang-4.0.0:
std::vector<StructData> test_struct_data(const size_t N) {
std::vector<StructData> data(N);
std::transform(data.begin(), data.end(), data.begin(), [N](auto item) {
std::random_device rd;
...
Python - Create list with numbers between 2 values?
...s to be 16+1 = 17
EDIT:
To respond to the question about incrementing by 0.5, the easiest option would probably be to use numpy's arange() and .tolist():
>>> import numpy as np
>>> np.arange(11, 17, 0.5).tolist()
[11.0, 11.5, 12.0, 12.5, 13.0, 13.5,
14.0, 14.5, 15.0, 15.5, 16....
How to sum array of numbers in Ruby?
...
Try this:
array.inject(0){|sum,x| sum + x }
See Ruby's Enumerable Documentation
(note: the 0 base case is needed so that 0 will be returned on an empty array instead of nil)
...
Associativity of “in” in Python?
... return 1 in [] in 'a'
.....:
In [122]: dis.dis(func)
2 0 LOAD_CONST 1 (1)
3 BUILD_LIST 0
6 DUP_TOP
7 ROT_THREE
8 COMPARE_OP 6 (in)
11 JUMP_IF_FAL...
JavaScript - cannot set property of undefined
... data: c
};
};
If you're in an environment that supports ES2015 features, you can use computed property names:
d = {
[a]: {
greetings: b,
data: c
}
};
share
|
improve th...
Understanding Linux /proc/id/maps
... following fields:
address perms offset dev inode pathname
08048000-08056000 r-xp 00000000 03:0c 64593 /usr/sbin/gpm
address - This is the starting and ending address of the region in the process's address space
permissions - This describes how pages in the region can be accesse...
SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
...
Since 3.24.0 SQLite also supports upsert, so now you can simply write the following
INSERT INTO visits (ip, hits)
VALUES ('127.0.0.1', 1)
ON CONFLICT(ip) DO UPDATE SET hits = hits + 1;
...
Is there a difference between using a dict literal and a dict constructor?
...
10 Answers
10
Active
...
Access an arbitrary element in a dictionary in Python
... |
edited May 15 at 15:06
gmelodie
19011 silver badge1616 bronze badges
answered Jun 22 '10 at 23:28
...
Bash, no-arguments warning, and case decisions
...
if [[ $# -eq 0 ]] ; then
echo 'some message'
exit 0
fi
case "$1" in
1) echo 'you gave 1' ;;
*) echo 'you gave something else' ;;
esac
The Advanced Bash-Scripting Guide is pretty good. In spite of its name, it does treat...