Fastest way to determine if an integer"s square root is an integer

I'm looking for the fastest way to determine if a long value is a perfect square (i.e. its square root is another integer). I've done it the easy way, by using the built-in Math.sqrt() function, but I'm wondering if there is a way to do it faster by restricting yourself to integer-only domain. Maintaining a lookup table is impratical (since there are about 2 ^31.5 integers whose square is less than 2 ⁶³ ).

How to check if a number is a power of 2

Today I needed a simple algorithm for checking if a number is a power of 2.

How to translate this Math Formula in PHP?

I'm trying to convert a Math Formula into PHP code.

You can see the formula in the accepted answer here: Applying a Math Formula in a more elegant way (maybe a recursive call would do the trick) .

Numerical library for Scala

I'm looking for a library to do numerical computing in Scala (or Java, although something that can use scala functions would be way nicer!) with at least the following capabilities:

Why Math.min() > Math.max()?

When I type in an array into the parameter of the javascript math minimum and maximum functions, it returns the correct value:

Simple statistics - Java packages for calculating mean, standard deviation, etc

Could you please suggest any simple Java statistics packages?

I don't necessarily need any of the advanced stuff. I was quite surprised that there does not appear to be a function to calculate the Mean in the java.lang.Math package...

MathML and Java

I've been doing some research for a mathematical Android related project I'd like to embark upon and I stumbled across for the first time MathML.

Android - calculating and storing the answer of an arithmetic expression

What would be best way to get the answer to this question which is using random numbers and random operators.