Rank: Member Groups: Registered
Joined: 06/02/2012(UTC) Posts: 13 Location: Poland / Wroclaw Was thanked: 1 time(s) in 1 post(s)
|
omorr wrote:Hello Rafal,
Thanks for the reply. On my second thoughts, I think that nothing is strange if we look at this like a symbolic expression. For instance: sum(el(x,i),i,-3,2)=el(x,-3)+el(x,-2)+el(x,-1)+el(x,0)+el(x,1)+el(x,2) Therefore, we can accept that symbolic engine accepts any index number, but not numerical. As you sad, only integers greater or equal to 1. Hope I am right about all of this.
Regards, Radovan If we assume that the indicator of the element is a number lying on the axis of integers, and we treat it as an ordinal it seems to me that, yes, ther`s nothing strange. On the other hand, assuming that it is an element in the first quadrant of the Cartesian, that is part of the real numbers possible to the physical, "touchable" definition, than it is not. The real thing is to have (n>0) or not have (n=0) an apple, it isn`t physically possible to have negative number of apples (n<0), this statement is a virtual, contractual. While looking at the table You can only say if ther`s an apple (or more apples), or ther`s none. Therefore, while building a vector/matrix, an element can either exist or not, you can not build a matrix for which the indicator of elements will not be possible for defining, that is they will lay in negative part of Cartesian. I hope that my understanding isn`t wrong. |