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What is more efficient? Using pow to square or just multiply it with itself?
...lliseconds>(std::chrono::high_resolution_clock::now() - from).count() * 1.0e-6;
}
private:
std::chrono::high_resolution_clock::time_point from;
};
int main (int argc, char* argv[])
{
double total;
Timer timer;
total = 0.0;
timer.start();
for (double i = 0.0; i < 1.0; i...
Adding a column to an existing table in a Rails migration
...n to it and then call
rake db:migrate
This will work if you have rails 3.1 onwards installed in your system.
Much simpler way of doing it is change let the change in migration file be as it is.
use
$rake db:migrate:redo
This will roll back the last migration and migrate it again.
...
Random / noise functions for GLSL
...es yields 0.0, all ones yields the next smallest representable value below 1.0.
float floatConstruct( uint m ) {
const uint ieeeMantissa = 0x007FFFFFu; // binary32 mantissa bitmask
const uint ieeeOne = 0x3F800000u; // 1.0 in IEEE binary32
m &= ieeeMantissa; ...
Why doesn't C have unsigned floats?
...
C99 supports complex numbers, and a type generic form of sqrt, so sqrt( 1.0 * I) will be negative.
The commentors highlighted a slight gloss above, in that I was referring to the type-generic sqrt macro rather than the function, and it will return a scalar floating point value by truncation of...
C# short/long/int literal format?
...
var d = 1.0d; // double
var d0 = 1.0; // double
var d1 = 1e+3; // double
var d2 = 1e-3; // double
var f = 1.0f; // float
var m = 1.0m; // decimal
var i = 1; // int
var ui = 1U; // uint
var ul = 1UL; // ulong
var l ...
What's the equivalent of Java's Thread.sleep() in Objective-C/Cocoa?
...
Sleeping for one second in Objective C:
[NSThread sleepForTimeInterval:1.0f];
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Android and setting alpha for (image) view alpha
...(float) whose XML counterpart is android:alpha. It takes a range of 0.0 to 1.0 instead of 0 to 255. Use it e.g. like
<ImageView android:alpha="0.4">
However, the latter in available only since API level 11.
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Twitter bootstrap remote modal shows same content every time
...
For Bootstrap 3.1 you'll want to remove data and empty the modal-content rather than the whole dialog (3.0) to avoid the flicker while waiting for remote content to load.
$(document).on("hidden.bs.modal", function (e) {
$(e.target).re...
How to find the type of an object in Go?
... "reflect"
)
func main() {
b := true
s := ""
n := 1
f := 1.0
a := []string{"foo", "bar", "baz"}
fmt.Println(reflect.TypeOf(b))
fmt.Println(reflect.TypeOf(s))
fmt.Println(reflect.TypeOf(n))
fmt.Println(reflect.TypeOf(f))
fmt.Println(reflect.TypeOf(a))
}
Pr...
CSS: center element within a element
...xes.
.flex-container{
display: -webkit-box; /* OLD - iOS 6-, Safari 3.1-6, BB7 */
display: -ms-flexbox; /* TWEENER - IE 10 */
display: -webkit-flex; /* NEW - Safari 6.1+. iOS 7.1+, BB10 */
display: flex; /* NEW, Spec - Firefox, Chrome, Opera */
justify-content: center;
a...