Vanitygen CDF vs. Mining CDF

[Phedwell]

If I run Vanitygen to look for a unique address and I hit 50% CDF during the calculations, does this mean I have tried 1/2 of the possible hash combinations for that unique address? So, at most I will spend an equal amount of time hashing the rest of the possible combinations before finding a solution, assuming the solution is the very last hash I try.

Am I also correct in my understanding that BTC mining CDF works a little different because the block we are all trying to solve changes every 10 minutes? So if I am solo mining and hit 50% CDF, I am not guaranteed to solve a block in another increment of time equal to the first 50%. In fact I may never solve a block in which case my CDF gets closer and closer to 100% but never quite reaches it.

In the first case CDF seems like a linear function and in the second case CDF seems very non-linear.

I tried searching for the answer without much luck.

[DeathAndTaxes]

CDF works the same way in both cases (all CDF always work the same way).  In theory if you have infinitely bad luck you could never not in a billion years find a solution for your vanitygen prefix.   That is very unlikely but it could happen.  For Bitcoin mining the fact that the previous block changes periodically makes no difference.  There is no "progress" towards a probabilistic solution.  You either solve it or you don't.

In both Vanitygen and bitcoin mining if your 50% CDF was 1 hour there is a 50% chance you will find a solution in less than or equal to 1 hour.  This doesn't mean you have a 100% chance in 2 hours. There is no 100% chance even in 1,000,000 hours (although it might be 99.999999999999999999999999999999999999999999999999%).

Also I assume it is just a typo but in vanitygen (just like in Bitcoin mining) you aren't looking for a specific unique solution but rather one of any number of the quadrillions of possible solution which match the prefix. 

[Phedwell]

...in vanitygen (just like in Bitcoin mining) you aren't looking for a specific unique solution but rather one of any number of the quadrillions of possible solution which match the prefix. 

Thanks. That was my mistake, forgetting there are way more than just a single solution when using vanitygen.