Difference between k-simplex and affine k-simplex

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A k-simplex requires its vertices to be affinely independent, while an affine k-simplex is derived from a standard simplex through affine transformations, which include linear transformations and translations. The discussion clarifies that both terms can be seen as equivalent, with the distinction lying in the context of their definitions. Affine transformations maintain collinearity and segment ratios, which is crucial for understanding affine simplices. The confusion arises from varying interpretations of the terms, but the consensus is that they refer to the same geometric concept under different conditions. Overall, the relationship between k-simplex and affine k-simplex is nuanced but fundamentally interconnected.
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Homework Statement


http://en.wikipedia.org/wiki/Affine_simplex

Can someone please explain the difference between a k-simplex and an affine k-simplex? Is the difference just that in a k-simplex, the points do not have to be affinely independent? On the wikipedia page, they say in the introduction that the points need to be affinely independent even for a k-simplex.

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I was say, judging on that Wikipedia page, that a simplex and an affine simplex are the same thing. Of course, Wiki isn't entirely correct. Have you seen the terms used in different ways? Could you tell us where you have used the terms used?
 
A regular simplex is one with vertices at the standard basis vectors. An affine simplex is an affine transformation (linear transform + a translation) of the standard simplex. Affine transformations preserve colinearity and ratios of line segments of the same line. An affine simplex is a k-simplex.
 
cristo said:
I was say, judging on that Wikipedia page, that a simplex and an affine simplex are the same thing.

OK good, that would resolve my confusion.

cristo said:
Of course, Wiki isn't entirely correct. Have you seen the terms used in different ways? Could you tell us where you have used the terms used?

No I haven't seen them used in different ways.
 
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