Choose function in Java math? [duplicate] - java

This question already has answers here:
Combinatoric 'N choose R' in java math?
(17 answers)
Closed 8 years ago.
Sorry about the ambiguous title, I basically need to know how to use the choose function in java, to work out the chance of something happening, for example say I wanted to work out my chance of winning the lottery, on a calculator I'd do:
QUANTITY_OF_LOTTERY_NUMBERS CHOOSE 6
and that would return the chance of those six numbers appearing at random. I believe it's called the binomial theorem, but I dropped out of college before I could learn anything else about it :P
Anyway, if you do 49 choose 6 on Google for example, you'll see the function I'm trying to use
Question: How do I implement this function in Java code?

Apache Commons Math has it. If you are curious, you can read about Pascal's triangle.
http://commons.apache.org/proper/commons-math/apidocs/org/apache/commons/math3/util/CombinatoricsUtils.html#binomialCoefficient(int, int)

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How to set sth. on infinity in Java? [duplicate]

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How to implement infinity in Java?
(11 answers)
Closed 5 years ago.
I want to implement the dijkstra algorithm and have to set each note at the beginning to infinity.
I would like to know, if there is any function in Java which makes it easy.
Double.POSITIVE_INFINITY if you are using Double to store your data.
Also note that this is not a number, which is nice depending on what you want to do. Double supports this concept.

Why should java variable names start with lowercase characters? [duplicate]

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camel case method names
(12 answers)
Closed 7 years ago.
I do not understand what the difference between
int Hello ;
and
int hello ;
is .
Does it make a big difference if i use upper case Characters ?
That's because of Java Convention!
Actually, you can write a program like the way you're imagining but, you won't be following any pattern.......If you become a real programmer someday, you'll understand that patterns exist to make things better and easier.....

Outputting X^n without caret [duplicate]

This question already has answers here:
Subscript and Superscript a String in Android
(15 answers)
Closed 8 years ago.
I am writing a simple android app and I would like to set the text of a button to be X^n but I want it to look the same way as it would if you would write it on a piece of paper( for example 2⁶).
I know there are several unicode characters that does it for a small group of numbers but I am looking for a generel function (or any other way) that takes two integers and output the first by the power of the second. For example:
int X=2;
int n=6;
function(X , n) ==> 2⁶
I know a similar question was asked here before but its answers were not sufficient because I want to use variables' values and not actual numbers;
Thanks!
You can use html's <sup> tags for that:
button.setText(Html.fromHtml("X<sup>n</sup>"));

Java : String representation from Integer [duplicate]

This question already has answers here:
How to convert number to words in java
(31 answers)
Closed 9 years ago.
I'm having a list of Integer from 1 to 100. If I loop through the list, I wanted to make the output as,
"One"
"Two" .....
"Hundred"
Is there any direct method in Java to obtain the above output?
No such method or class has been provided by JDK.
You can use the code mentioned here or here for reference purpose.
switch case are used to meet that requirement: Here
is source code.
Answer of this question described here: How to convert number to words in java
Officially this is not possible or no standard library available by native Java.
Don't duplicate.
There is none in the official Java libraries. However, the International Components for Unicode project has a RuleBasedNumberFormat with those capabilities. It even has a SPELLOUT constant.

How to convert string to math equation? [duplicate]

This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
Java: Parse a mathematical expression given as a string and return a number
Hello there,
I would like to ask you, if exist some way how to convert string "1+2+3" to math equation? Exist for this purpose some function or method in Java?
Thanks for hints.
It's not part of the standard API.
But I implemented it in my project, you can have a look here.
https://github.com/MarkyVasconcelos/Towel/wiki/Expression
This would necessarily depend on the implementation of the Equation class you're using. Check its API.

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