I need to access the sqrt method in my rails app. I believe I need the Math library for this: irb(main):010:0> require "Math" LoadError: no such file to load -- Math Could someone tell me where I download the Math library from, and where I should place it on my file system? I can't seem to find any documentation explaining this. Lindsay

on 2006-03-23 12:38

on 2006-03-23 12:44

On 23-Mar-06, at 6:38 AM, Lindsay Boyd wrote: > I need to access the sqrt method in my rails app. I believe I need the > Math library for this: > > irb(main):010:0> require "Math" > LoadError: no such file to load -- Math > > Could someone tell me where I download the Math library from, and > where > I should place it on my file system? I can't seem to find any > documentation explaining this. It is already there, you can call it in a couple of ways: puts Math.sqrt(2) or if you want a lot of Math methods you can use include to get the Math module's methods without the Math prefix: include Math puts sqrt(2) You should read up on what include does before using it. Hope this helps, Mike -- Mike Stok <mike@stok.ca> http://www.stok.ca/~mike/ The "`Stok' disclaimers" apply.

on 2006-03-23 12:50

Thanks Mike - I was trying '2.sqrt'. No wonder that didn't work!

on 2006-03-23 14:58

```
Lindsay Boyd:
> Thanks Mike - I was trying '2.sqrt'. No wonder that didn't work!
Yeah, I've always wanted to do that kind of thing, too... let's try
this:
class Numeric
Math.methods(false).each do |m|
define_method(m) {|*args| Math.send(m, self, *args) }
end
end
2.sqrt #=> 1.4142135623731
Floating-pointilicius!
Cheers,
Dave
```

on 2006-03-24 00:23

```
> 2.sqrt #=> 1.4142135623731
That's really elegant. I can see why Ruby has so many fans :-)
Lindsay
```