do i need to import math in java

Should I import a math library, and if so how?

stackoverflow.com › questions › 21972105 › should-i-import-a-math-library-and-if-so-how

E and PI are not functions, they're static fields (data members). That code will output their values correctly. You don't have to import anything, the Math class is in the java.lang package, which is imported by default. (It's the only package imported by default, I believe.)

Answer from T.J. Crowder on Stack Overflow

Stack Overflow

stackoverflow.com › questions › 21972105 › should-i-import-a-math-library-and-if-so-how

java - Should I import a math library, and if so how? - Stack Overflow

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E and PI are not functions, they're static fields (data members). That code will output their values correctly. You don't have to import anything, the Math class is in the java.lang package, which is imported by default. (It's the only package imported by default, I believe.)

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You don't have to import anything here. The java.lang.Math class should already be available as java.lang package is imported by default

reddit.com › r/learnjava › how come i didn't need to import java.lang.math for my code?

r/learnjava on Reddit: How come I didn't need to import java.lang.Math for my code?

January 24, 2015 -

I had this line of code:

int generator = 1 + (int) (Math.random() * 19);

http://puu.sh/sGVps/b318650d6b.png

The program I create works perfectly but i was wondering why I didn't need to import lang.math despite using random.

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java.lang is always imported by default for Java.

Discussions

Is the Math class a standard class of Java? - Stack Overflow

You definitely do not have to import it like the Scanner class, which isn't a standard class of Java. Perhaps I do not understand what a standard class is. Can someone explain this for me? ... Yes, you do have to import Math to use it. But most of its methods are static, so you'd need to do either ... More on stackoverflow.com

stackoverflow.com

Why does the **Math** class not need to be imported?

Find step-by-step Computer science solutions and the answer to the textbook question Why does the Math class not need to be imported?. More on quizlet.com

quizlet.com

1

[JAVA]Why do we have to import classes like Random and Scanner? Why not just have it built into the language?

EDIT: Based on other responses below, let me clarify how I'm responding. I'm assuming OP genuinely is asking why the classes cannot be built in. You certainly could do an implicit import of the necessary classes instead of building them into the language itself. I raise three issues in my post, but with an implicit import, only the first issue remains. The responses here about memory are absolutely not correct. Why not just have all of these classes already built in the language It adds complexity to the language for no gains. The only advantage you get is nominal: not having to type import. However, you pay a huge price. First, you introduce a large number of reserved keywords into the language. Let's say you create a new PRNG. What do you call the class? Random? No, you can't do that, because the name is already in use. So everyone has to be aware of all the different class names that are built in. And how many classes are we talking about here? Are all the class names even unique? Can you even state that across the Java platform, there are no class names that are the same? Second, you create implementation complexity. When you state that Scanner is actually a part of the language, it has to implemented as a new grammar rule. Lexing and parsing and optimization now need to take this name into account, for no benefit, because like I said, these classes don't actually have any unique grammar behind them. You do not want exploding complexity to implement and maintain in your compilers. Third, you create language inflexibility. You can't create a lean version and implementation of the Java platform, because to implement the language, you have to implement all those classes. They are built into the language itself, after all. More on reddit.com

r/learnprogramming

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July 19, 2014

How come I didn't need to import java.lang.Math for my code?

java.lang is always imported by default for Java.

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would Math fall into this category?

Yes. It is documented as part of the JDK javadoc (since JDK 1.0) so you are guaranteed that it will exist in any JRE you'll ever encounter.

Note that since it resides in java.lang, you do not have to import it explicitly; you could:

import java.lang.Math;

but since all classes in java.lang are automatically imported (that includes String and Integer for instance), you need not do that.

This is a peculiar class in the sense that it cannot be instantiated and it only contains static methods and constants; apart from that you are sure to have it available, and that methods and constants obey the defined contract.

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It comes with the SDK, if that is what "standard" meant.

It is part of the java.lang package, thus does not require import.

Sololearn

sololearn.com › en › Discuss › 1527906 › does-the-math-class-needs-to-be-imported-in-java-because-im-tring-to-use-the-mathpow-and-doesnt-work-and-if-so-how-do-i-do-it

Does the math class needs to be imported in java because im tring to use the math.pow and doesnt work.. and if so how do i do it | Sololearn: Learn to code for FREE!

I mean, you could import static java.lang.Math; 1st Oct 2018, 5:41 PM · LunarCoffee · 0 · thank you it worked but tring to go on and running the code tells me 'time limit exceeded' whats up with that? any idea? 1st Oct 2018, 4:19 PM · ThermalBlast22 · 0 · wierd its not long at all i think but its my first one so what do i know..

Vivatechnology

press.vivatechnology.com › Textbook › 411141 › 96EI2u › HowToImportMathInJava.pdf

How To Import Math In Java

EN COURS DE DEV · press.vivatechnology.com en cours de dev · — Coding is Love

Quizlet

quizlet.com › science › computer science

Why does the Math class not need to be imported? | Quizlet

We don't have to import Math class because it is in the java.lang package which provides fundamental classes for the programming in Java language (e.g.

FavTutor

favtutor.com › blogs › java-math-class

Math Class in Java & Methods (with Examples)

October 9, 2023 - Here are some tips to keep in mind: Avoid Redundant Imports: While it's possible to import the Math class using the import statement, it's not always necessary. If you only need to use a few methods or variables from the Math class, it's better ...

reddit.com › r/learnprogramming › [java]why do we have to import classes like random and scanner? why not just have it built into the language?

r/learnprogramming on Reddit: [JAVA]Why do we have to import classes like Random and Scanner? Why not just have it built into the language?

July 19, 2014 -

for example every time you want to ask the user for input or a random number generator you have to type.

import java.util.Scanner;
import java.util.Random;

at the top of your code. Then you have to create the objects inside the main method.

public static void main(String[] args){
    Scanner keyboard = new Scanner(System.in);
    Random rand = new Random();
}

Why do we have to do the import command? Why not just have all of these classes already built in the language, then we can just create the objects?

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EDIT: Based on other responses below, let me clarify how I'm responding. I'm assuming OP genuinely is asking why the classes cannot be built in. You certainly could do an implicit import of the necessary classes instead of building them into the language itself. I raise three issues in my post, but with an implicit import, only the first issue remains. The responses here about memory are absolutely not correct. Why not just have all of these classes already built in the language It adds complexity to the language for no gains. The only advantage you get is nominal: not having to type import. However, you pay a huge price. First, you introduce a large number of reserved keywords into the language. Let's say you create a new PRNG. What do you call the class? Random? No, you can't do that, because the name is already in use. So everyone has to be aware of all the different class names that are built in. And how many classes are we talking about here? Are all the class names even unique? Can you even state that across the Java platform, there are no class names that are the same? Second, you create implementation complexity. When you state that Scanner is actually a part of the language, it has to implemented as a new grammar rule. Lexing and parsing and optimization now need to take this name into account, for no benefit, because like I said, these classes don't actually have any unique grammar behind them. You do not want exploding complexity to implement and maintain in your compilers. Third, you create language inflexibility. You can't create a lean version and implementation of the Java platform, because to implement the language, you have to implement all those classes. They are built into the language itself, after all.

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Why not just have all of these classes already built in the language It's important to know the difference between "the language" and the "standard library". The language mostly consists of the reserved words and how you use them. For example, defining classes and creating objects. The standard library is all of the things you can use with the language without having to add additional libraries. In java this is generally called the JDK. There is a special package in the JDK where everything in it is automatically imported, as you're requesting. This is the packaged named 'java.lang'. This is why, for example, you don't have to ever import String or Math. So, you're basically asking, why isn't the entire JDK under java.lang (or, why not have the entire JDK in a nameless package)? The biggest problem would be name collisions. There are thousands of classes in the JDK and you'd never be able to reuse any of those names. It would also likely make compiling noticeably longer as it'd have to find all the definitions from a huge flat listing instead of a defined hierarchy. There are many other reasons but I'll let you look it up. The concept here is called namespaces. Good question and good luck!

Quora

quora.com › How-do-I-import-a-math-class-in-Java

How do I import a math class in Java?

Answer (1 of 4): Math class is from java.lang package. So you dont have to import Math class. Also the methods and variables in Math class are static. So you can call them using class name.

Sololearn

sololearn.com › en › Discuss › 2816992 › how-can-i-import-javalangmaths-to-use-exponents-mathpow

How can I import java.lang.maths to use exponents? (Math.pow) | Sololearn: Learn to code for FREE!

June 20, 2021 - No need to import Math class.. You can directly use Math.pow(2,3) returns 8.0 ... Katharina Hohenfels round, pow, ceil are methods of Math class. As you have already used Math.round() without importing so you can also use Math.pow() without ...

Coderanch

coderanch.com › t › 629237 › java › java-lang-Math-methods-import

Use java.lang.Math methods without import in IDE [Solved] (Beginning Java forum at Coderanch)

February 22, 2014 - programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other Pie Elite all forums · this forum made possible by our volunteer staff, including ... ... I am able to use a Math method without importing the java.lang.Math.

TutorialsPoint

tutorialspoint.com › static-import-the-math-class-methods-in-java

Static import the Math Class Methods in Java

July 30, 2019 - The Math class is not required along with the method sqrt() as static import is used for the java.lang package. The number num and its square root is displayed. A code snippet which demonstrates this is as follows: double num = 36.0; System.out.println("The number is: " + num); System.out....

Educative

educative.io › answers › how-to-use-the-mathrandom-method-in-java

How to use the Math.random() method in Java

The range of this random number ... number. This method belongs to the java.lang.Math class, so you need to import this class before implementing this method....

DataCamp

datacamp.com › doc › java › import

import Keyword in Java: Usage & Examples

By importing static methods from the java.lang.Math class, you can directly use methods like sqrt and pow without prefixing them with Math.. Avoid Unnecessary Imports: Only import the classes or packages you need. Unnecessary imports can clutter your code and may lead to ambiguity.