Dilation (metric space)

In mathematics, a dilation is a function ${\displaystyle f}$ from a metric space into itself that satisfies the identity

for all points ${\displaystyle (x,y)}$, where ${\displaystyle d(x,y)}$ is the distance from ${\displaystyle x}$ to ${\displaystyle y}$ and ${\displaystyle r}$ is some positive real number.

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