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.)
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.)
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
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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.
It comes with the SDK, if that is what "standard" meant.
It is part of the java.lang package, thus does not require import.
I have been trying to use the Apache Commons Math library in my code. I have been having trouble importing it. I'm new to downloading libraries/packages outside of the built-in java packages. It feels like I have tried everything, and I might just be missing an obvious detail. I am using a Windows 11 machine.
I have tried the following with the most recent release of the Apache Commons Math library (3.6.1) and the most recent version (4.0).
The error that I get every compile time is: package org.apache.commons does not exist.
I have installed IntelliJ IDE and tried
adding it as a library in the project structure (under project settings)
and adding it as a dependency in the
build.gradlefile (implementation 'org.apache.commons:commons-math4:4.0').
I have installed Eclipse IDE and tried
importing the JAR files into the
srcfolder.I have tried following the steps in this article (add User Library -> add external JAR(s) -> fill in
Javadoc location-> configure build path).
I have tried adding the directories containing the JAR files to CLASSPATH using Control Panel (edit system variables).
I'm still somewhat confused as to why there are multiple JAR files in the directory that you get after unzipping the library and as to which one(s) I'm supposed to be using directly. But, I tried extracting the class files using the jar xf command in the terminal from what I thought were the important JAR files (commons-math4-legacy-4.0-beta1.jar and commons-math3-3.6.1.jar). I then tried
adding the resulting
orgdirectory toCLASSPATHand tediously grouping all of the class files from all of the subdirectories into one single directory and adding that directory to
CLASSPATH.
I have tried using these directories by compiling with javac -cp path/to/JAR/file/filename.jar *.java, which by my understanding does the same thing as adding them to CLASSPATH in Control Panel but I tried it anyway.
I even tried downloading the source version of the library and collecting all of the .java files into one single directory.
I also tried what the answerer suggested here, and it did not work.
Do you know what I am doing wrong? Let me know if I need to provide any more info. Thank you!