I understand how complex numbers are derived from real numbers. Namely when you have a sqrt of a negative number you must have an answer of some kind, but this answer cannot be in the real number system, therefore you need another number system which you call complex.
What I do not understand is which problem in calculation, either calculation in real numbers or in complex numbers, you cannot solve within those systems, for which you need another system like the quaternion. Thus I fail to see how the quaternion system can be derived from the complex or real number system from a perspective of calculation.
To me it therefore seemed that someone wanted a 3dimensional number system to represent problems in graphing. This person then found out that the 3rd dimension in the number system made no sense (the relation of this 3rd dimension with complex and real numbers is unclear) and therefore defined a 4th dimension in order to make sense of this 3rd dimension. What I think at this moment is that he has not derived quaternions from complex and real numbers but instead simply chose to define another system.
However: Since I am a noob and this guy was clearly a genius, I presume that I fail to see something. And the relevant thing that I fail to see is: How are quaternions derived from complex and real numbers from a calculation perspective. (Not from a geometrical perspective).