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How to scale down a range of numbers with a known min and max value
...n
which is what we want. So we need to do a translation and a scaling. Now if instead we want to get arbitrary values of a and b, we need something a little more complicated:
(b-a)(x - min)
f(x) = -------------- + a
max - min
You can verify that putting in min for x now give...
Which timestamp type should I choose in a PostgreSQL database?
...TE TABLE my_tbl (
my_timestamp TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
CHECK(EXTRACT(TIMEZONE FROM my_timestamp) = '0')
);
test=> SET timezone = 'America/Los_Angeles';
SET
test=> INSERT INTO my_tbl (my_timestamp) VALUES (NOW());
ERROR: new row for relation "my_tbl" violates check...
How to generate a random string of a fixed length in Go?
...eneral solution we're improving is this:
func init() {
rand.Seed(time.Now().UnixNano())
}
var letterRunes = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
func RandStringRunes(n int) string {
b := make([]rune, n)
for i := range b {
b[i] = letterRunes[rand.Intn(...
Check time difference in Javascript
...
I never know if dates in this format will be parsed as d/m/y or m/d/y. The official formats accepted are here (whatever Date.parse() accepts is valid), developer.mozilla.org/en/JavaScript/Reference/Global_Objects/…
...
Check if a string contains a string in C++
...proach" << std::endl;
start = high_resolution_clock::now();
for(size_t i=0; i<haystacksCount; ++i)
{
if(haystacks[i].find(needle) != std::string::npos)
{
sink = !s...
Python speed testing - Time Difference - milliseconds
...roseconds
>>> import datetime
>>> a = datetime.datetime.now()
>>> b = datetime.datetime.now()
>>> c = b - a
>>> c
datetime.timedelta(0, 4, 316543)
>>> c.days
0
>>> c.seconds
4
>>> c.microseconds
316543
Be aware that c.micros...
How to get start and end of day in Javascript?
...0 * 60 * 24; // 24 hours in milliseconds
let startOfDay = Math.floor(Date.now() / interval) * interval;
let endOfDay = startOfDay + interval - 1; // 23:59:59:9999
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How to get UTC time in Python?
...
Try this code that uses datetime.utcnow():
from datetime import datetime
datetime.utcnow()
For your purposes when you need to calculate an amount of time spent between two dates all that you need is to substract end and start dates. The results of such subst...
How to subtract 30 days from the current datetime in mysql?
...
SELECT * FROM table
WHERE exec_datetime BETWEEN DATE_SUB(NOW(), INTERVAL 30 DAY) AND NOW();
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_date-add
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Is JavaScript a pass-by-reference or pass-by-value language?
...itive types (number, string, etc.) are passed by value, but objects are unknown, because they can be both passed-by-value (in case we consider that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object holds the o...