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heroku - how to see all the logs
...ve a small app on heroku. Whenever I want to see the logs I go to the command line and do
19 Answers
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What is the fastest way to get the value of π?
... fastest π I know of is the one with the digits hard coded. Looking at Pi and Pi[PDF], there are a lot of formulae.
Here is a method that converges quickly — about 14 digits per iteration. PiFast, the current fastest application, uses this formula with the FFT. I'll just write the formula, since...
The smallest difference between 2 Angles
...
Simpler and makes more sense read out loud, though effectively the same thing, first bti figures out the angle, second part makes sure its always the smaller of the 2 possible angles
– Tom J Nowell
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How can I format a nullable DateTime with ToString()?
... format)
=> dt == null ? "n/a" : ((DateTime)dt).ToString(format);
And starting in C# 6, you can use the null-conditional operator to simplify the code even more. The expression below will return null if the DateTime? is null.
dt2?.ToString("yyyy-MM-dd hh:mm:ss")
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Define variable to use with IN operator (T-SQL)
...can even pass whole table variables in as a parameter to stored procedures and use it in a join or as a subselect in the IN clause.
DECLARE @list TABLE (Id INT)
INSERT INTO @list(Id)
SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4
SELECT
*
FROM
myTable
JOIN @list ...
Using comparison operators in Scala's pattern matching system
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You can add a guard, i.e. an if and a boolean expression after the pattern:
a match {
case 10 => println("ten")
case x if x > 10 => println("greater than ten")
case _ => println("less than ten")
}
Edit: Note that this is more than...
What are carriage return, linefeed, and form feed?
...when the name was coined. This is commonly escaped as \r, abbreviated CR, and has ASCII value 13 or 0x0D.
Linefeed means to advance downward to the next line; however, it has been repurposed and renamed. Used as "newline", it terminates lines (commonly confused with separating lines). This is co...
How to print a number with commas as thousands separators in JavaScript
I am trying to print an integer in JavaScript with commas as thousands separators. For example, I want to show the number 1234567 as "1,234,567". How would I go about doing this?
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Are strongly-typed functions as parameters possible in TypeScript?
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Sure. A function's type consists of the types of its argument and its return type. Here we specify that the callback parameter's type must be "function that accepts a number and returns type any":
class Foo {
save(callback: (n: number) => any) : void {
callback(42);
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Timer function to provide time in nano seconds using C++
...ed about running the function repeatedly in a loop is correct.
For Linux (and BSD) you want to use clock_gettime().
#include <sys/time.h>
int main()
{
timespec ts;
// clock_gettime(CLOCK_MONOTONIC, &ts); // Works on FreeBSD
clock_gettime(CLOCK_REALTIME, &ts); // Works on Li...