Odds Conversion question

[Mike]

I'm finishing up a little script and am having some math issues converting american odds to decimal odds. The formula I am currently using works most of the time, but sometimes it gives me odds that are not in line with other bookies offering similar odds and it is making the comparison out of whack.

Here is what I am using to convert american to decimal:

am >= 100
dec = 1 + (am / 100)

am <= -100
dec = 1 - (am / 100)

Is this correct?

[pokerprop]

First one is correct, but the second one is not and should be:

am <= -100
dec = 1 + (100 / am)

[Mike]

Thanks, was hoping you'd chime in. I was showing New England at -22.0, lol.

[JTJagger]

I've built a PHP library of common sportsbetting functions, drop me a message if you'd like it.

Also it should be:
am <= -100
dec = 1 + (100 / abs(am))

Where abs(am) is the absolute (ie, positive) value of am

[gregn]

I've built a PHP library of common sportsbetting functions, drop me a message if you'd like it.

you got PM