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Next: <a href="Exact-Division.html#Exact-Division" accesskey="n" rel="next">Exact Division</a>, Previous: <a href="Divide-and-Conquer-Division.html#Divide-and-Conquer-Division" accesskey="p" rel="prev">Divide and Conquer Division</a>, Up: <a href="Division-Algorithms.html#Division-Algorithms" accesskey="u" rel="up">Division Algorithms</a> &nbsp; [<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<h4 class="subsection">15.2.4 Block-Wise Barrett Division</h4>
<p>For the largest divisions, a block-wise Barrett division algorithm is used.
Here, the divisor is inverted to a precision determined by the relative size of
the dividend and divisor. Blocks of quotient limbs are then generated by
multiplying blocks from the dividend by the inverse.
</p>
<p>Our block-wise algorithm computes a smaller inverse than in the plain Barrett
algorithm. For a <em>2n/n</em> division, the inverse will be just <em>ceil(n/2)</em> limbs.
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