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Questions tagged [casting]

Casting is a process where an object type is explicitly converted into another type if the conversion is allowed. This process might lead to a change in value.

Some algorithms have significant performance differences for different data-types, for example, calculating the N-dimensional median is much is much faster for integers than float type data. Therefore, the use of casting can be important for code performance.

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Safely casting long to int in Java

What's the most idiomatic way in Java to verify that a cast from long to int does not lose any information? This is my current implementation: public static int safeLongToInt(long l) { int i = (int)l; if ((long)i != l) { throw new…
Brigham
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How to convert an array to object in PHP?

How can I convert an array like this to an object? [128] => Array ( [status] => "Figure A. Facebook's horizontal scrollbars showing up on a 1024x768 screen resolution." ) [129] => Array ( [status] => "The other day at…
streetparade
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How to convert string to boolean php

How can I convert string to boolean? $string = 'false'; $test_mode_mail = settype($string, 'boolean'); var_dump($test_mode_mail); if($test_mode_mail) echo 'test mode is on.'; it returns, boolean true but it should be boolean false.
Run
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Casting vs using the 'as' keyword in the CLR

When programming interfaces, I've found I'm doing a lot of casting or object type conversion. Is there a difference between these two methods of conversion? If so, is there a cost difference or how does this affect my program? public interface…
Frank V
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Convert boolean to int in Java

What is the most accepted way to convert a boolean to an int in Java?
hpique
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Cast Int to enum in Java

What is the correct way to cast an Int to an enum in Java given the following enum? public enum MyEnum { EnumValue1, EnumValue2 } MyEnum enumValue = (MyEnum) x; //Doesn't work???
Maxim Gershkovich
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Cast Double to Integer in Java

Any way to cast java.lang.Double to java.lang.Integer? It throws an exception "java.lang.ClassCastException: java.lang.Double incompatible with java.lang.Integer"
4lex1v
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Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL

I want to extract just the date part from a timestamp in PostgreSQL. I need it to be a postgresql DATE type so I can insert it into another table that expects a DATE value. For example, if I have 2011/05/26 09:00:00, I want 2011/05/26 I tried…
keren
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Does it make sense to use "as" instead of a cast even if there is no null check?

In development blogs, online code examples and (recently) even a book, I keep stumbling about code like this: var y = x as T; y.SomeMethod(); or, even worse: (x as T).SomeMethod(); That doesn't make sense to me. If you are sure that x is of type…
Heinzi
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How do I convert all of the items in a list to floats?

I have a script which reads a text file, pulls decimal numbers out of it as strings and places them into a list. So I have this list: my_list = ['0.49', '0.54', '0.54', '0.55', '0.55', '0.54', '0.55', '0.55', '0.54'] How do I convert each of the…
snk
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Convert String to double in Java

How can I convert a String such as "12.34" to a double in Java?
TinyBelly
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C# : 'is' keyword and checking for Not

This is a silly question, but you can use this code to check if something is a particular type... if (child is IContainer) { //.... Is there a more elegant way to check for the "NOT" instance? if (!(child is IContainer)) { //A little ugly... silly,…
hugoware
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How do you cast a List of supertypes to a List of subtypes?

For example, lets say you have two classes: public class TestA {} public class TestB extends TestA{} I have a method that returns a List and I would like to cast all the objects in that list to TestB so that I end up with a List.
Jeremy Logan
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Integer division: How do you produce a double?

For this code block: int num = 5; int denom = 7; double d = num / denom; the value of d is 0.0. It can be forced to work by casting: double d = ((double) num) / denom; But is there another way to get the correct double result? I don't like casting…
walnutmon
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TypeScript or JavaScript type casting

How does one handle type casting in TypeScript or Javascript? Say I have the following TypeScript code: module Symbology { export class SymbolFactory { createStyle( symbolInfo : SymbolInfo) : any { if (symbolInfo ==…
Klaus Nji
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