Standard Deviation in Normal Distribution is Zero!

Normal distribution - Wikipedia, the free encyclopedia

http://upload.wikimedia.org/math/9/e...9a0b69fbf6.png

The very first formula you see, i'm having to use that.

Basically i'm writing a program for Naive Bayes Classifier.

One of the classes has a standard deviation of zero.

Now, i can't divide by Zero...so if something has a S.D is zero, i gather that all value's must equal the mean(which in my case annoyingly is also zero).

So, if the SD is zero, how can i use the formula there?