What does it mean if the cumulative normal = 1? What is the significance of cumulative normal = 1?
I am trying to program a game, however I have inherited code from another programmer. He
is using the cumulative norm. his code is outputting a value of one for a certain value
x, mean and standard deviation.
I have a product value which lets say is = 2.5.
The standard deviation is 0.625.
The x value was generated iteratively and eventually comes to 10.931456.
So are you saying that X or the mean is the 2.5,
x is the 10.93,
and the sd = 0.625?
Also that the probability of 2.5 being at the point x = 10.93 is 1?
 A: If I understand your question correctly, you have a normally distributed random variable $X$, and the program says that the probability that $X\le x$ is $1$. Now for a normally distributed random variable $X$, the probability that $X\le x$ can never be exactly equal to $1$, it must always be less than $1$.
However, the tails decay very rapidly, so we may have $P(X\le x)$ for all practical purposes. So for example we could easily have $P(X\le x)=1-10^{-12}$. For instance, the probability that a standard normal $Z$ is $\le 6$ is about $1-2\times 10^{-9}$. 
The programmer may have decided to round such a number to $1$. Or else, because of precision limitations, there is automatic rounding.  
Deciding to round is very sensible. When you are modelling a real phenomenon using the normal distribution, that distribution will never model the phenomenon exactly.  Sort of close is the best one can hope for.
Added: For your edited question, I do not know what the $2.5$ means. But the range from $2.5$ to $10.93$ is $8.43$, which is $8.43/0.625$ standard deviation units, about $13.5$ standard deviation units. That is an astoundingly large range, really quite inconsistent with a normal distribution. For most practical (or even impractical) purposes, in a normal there is virtually nothing $4$ standard deviation units or more away from the mean.
