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How to work with complex numbers in C?
...e into complex, use _Complex_I macro from complex.h:
float _Complex d = 2.0f + 2.0f*_Complex_I;
(actually there can be some problems here with (0,-0i) numbers and NaNs in single half of complex)
Module is cabs(a)/cabsl(c)/cabsf(b); Real part is creal(a), Imaginary is cimag(a). carg(a) is for c...
Precision String Format Specifier In Swift
...ill going to be NSString formatting:
println(NSString(format:"%.2f", sqrt(2.0)))
Extrapolating from python, it seems like a reasonable syntax might be:
@infix func % (value:Double, format:String) -> String {
return NSString(format:format, value)
}
Which then allows you to use them as:
...
Get Android API level of phone currently running my application [duplicate]
...Android 1.6 Donut
5 ECLAIR Android 2.0 Eclair
6 ECLAIR_0_1 Android 2.0.1 Eclair
7 ECLAIR_MR1 Android 2.1 Eclair
8 FROYO Android 2...
What is the difference between Spring, Struts, Hibernate, JavaServer Faces, Tapestry?
...modern, standardized and very nice equivalent of the above frameworks: JSF 2.0 and Facelets for the presentation, JPA 2.0 for the persistence, Dependency Injection, etc. For a new development, this is IMO a serious option, Java EE 6 is a great stack.
See also
Choosing a Java Web Framework now?
Ja...
Draw line in UIView
...orWithColor(context, [UIColor redColor].CGColor);
// Draw them with a 2.0 stroke width so they are a bit more visible.
CGContextSetLineWidth(context, 2.0f);
CGContextMoveToPoint(context, 0.0f, 0.0f); //start at this point
CGContextAddLineToPoint(context, 20.0f, 20.0f); //draw to t...
Convert between UIImage and Base64 string
...Data format
let imageData:NSData = NSData.init(contentsOfURL: url)!
Swift 2.0 > Encoding
let strBase64:String = imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)
Swift 2.0 > Decoding
let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64D...
JPA: How to have one-to-many relation of the same Entity type
...ip is the same. The general case is detailed in Section 2.10.2 of the JPA 2.0 spec.
Here's a worked example. First, the entity class A:
@Entity
public class A implements Serializable {
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
@ManyToOne
private A pa...
How do you test to see if a double is equal to NaN?
...------------------------------------------";
Double numerator = -2.0;
Double denominator = -2.0;
while (denominator <= 1) {
Double x = numerator/denominator;
Double y = new Double (x);
boolean z = y.isNaN();
System.out.println("y ...
Wait for page load in Selenium
How do you make Selenium 2.0 wait for the page to load?
47 Answers
47
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Split a string by another string in C#
...
As of .NET Core 2.0, there is an override that takes a string.
So now you can do "THExxQUICKxxBROWNxxFOX".Split("xx").
See https://docs.microsoft.com/en-us/dotnet/api/system.string.split?view=netcore-2.0#System_String_Split_System_String_S...