Throw the right exception when given an invalid dimension
Throw the right exception when given an invalid dimension

It used to throw a name error when creating the exception due to a bug.
Now it throws the proper exception.

UIKit0/HyperDex,tempbottle/HyperDex,jtk54/HyperDex,cactorium/HyperDex,vashstorm/HyperDex,pombredanne/HyperDex,vashstorm/HyperDex,jtk54/HyperDex,UIKit0/HyperDex,UIKit0/HyperDex,tempbottle/HyperDex,jtk54/HyperDex,hyc/HyperDex,rescrv/HyperDex,cactorium/HyperDex,UIKit0/HyperDex,rescrv/HyperDex,pombredanne/HyperDex,rescrv/HyperDex,tempbottle/HyperDex,tempbottle/HyperDex,jtk54/HyperDex,pombredanne/HyperDex,jtk54/HyperDex,cactorium/HyperDex,UIKit0/HyperDex,hyc/HyperDex,pombredanne/HyperDex,tempbottle/HyperDex,rescrv/HyperDex,UIKit0/HyperDex,rescrv/HyperDex,tempbottle/HyperDex,pombredanne/HyperDex,vashstorm/HyperDex,UIKit0/HyperDex,rescrv/HyperDex,cactorium/HyperDex,pombredanne/HyperDex,cactorium/HyperDex,jtk54/HyperDex,jtk54/HyperDex,tempbottle/HyperDex,rescrv/HyperDex,hyc/HyperDex,vashstorm/HyperDex,vashstorm/HyperDex,UIKit0/HyperDex,vashstorm/HyperDex,cactorium/HyperDex,rescrv/HyperDex,pombredanne/HyperDex,jtk54/HyperDex,hyc/HyperDex,hyc/HyperDex,vashstorm/HyperDex,hyc/HyperDex,hyc/HyperDex,cactorium/HyperDex,UIKit0/HyperDex,jtk54/HyperDex,rescrv/HyperDex,cactorium/HyperDex,vashstorm/HyperDex,cactorium/HyperDex,tempbottle/HyperDex,pombredanne/HyperDex,pombredanne/HyperDex,hyc/HyperDex,vashstorm/HyperDex,tempbottle/HyperDex