find the base 2 logarithm of a number in rust

To find the base 2 logarithm of a number in Rust, you can use the log2 function from the std::f64 module in the standard library.

Here is an example code snippet that demonstrates how to use this function:

main.rs
fn main() {
    let x = 8.0;
    let log_x = x.log2();
    println!("The base 2 logarithm of {} is {}.", x, log_x);
}
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In this example, we first define a variable x and initialize it to the value 8.0. We then call the log2 method on x to find its base 2 logarithm, and store the result in a variable called log_x. Finally, we print out the value of log_x using the println! macro.

The output of this program would be:

main.rs
The base 2 logarithm of 8 is 3.
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Note that the log2 function returns a f64 value, which represents the logarithm with a high degree of precision. If you need to round or truncate the result to an integer value, you can use the round, floor, or ceil methods on the result accordingly.