Interesting inner-product scans

ABSTRACT

The inner-product scan allows a straight-forward calculation of interest-bearing accounts or annuities without a loop in APL. It allows arbitrary deposit (or withdrawal) and interest each period. A defined scan operator for associative functions is provided to improve performance by avoiding the repeated reductions of increasingly long vectors that require +/ι n rather than n products.The idea of inner-product scans is developed through the use of rotation matrices to draw polygons and spirals and a connection matrix to implement a shift register that generates random bits.

REFERENCES

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