Lecture 3 Lll, Coppersmith
نویسندگان
چکیده
The idea behind the SizeReduce(B) subroutine is, in the Gram-Schmidt decomposition B = B̃ ·U, to shift the entries in the upper triangle of U by integers (via unimodular transformations), so that they lie in [−12 , 1 2). Because changing an entry of U may affect the ones above it (but not below it) in the same column, we must make the changes upward in each column. Formally, the algorithm works as follows:
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