Self-affine cascade
This the simplest case of non auto-similar generator, it has two invariant. The self-affine cascade are characterized by an anisotropy between two directions in space. If
measure the gap compared to the isotropic scale law between two directions, the matrix
is defined as :

is called the anisotropic exponent.
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In order to get an self-affine cascade, we operate in two direction, a division by two number
and
. As we have seen above, the intensities are distributed following a random variable generator.