Electrical computers: arithmetic processing and calculating – Electrical digital calculating computer – Particular function performed
Reexamination Certificate
2011-04-05
2011-04-05
Malzahn, David H (Department: 2193)
Electrical computers: arithmetic processing and calculating
Electrical digital calculating computer
Particular function performed
Reexamination Certificate
active
07921144
ABSTRACT:
A system and method for converting bases of floating point numbers using fixed-point computation includes tables having different related spacings of exponent indices. The tables are adapted to cross-reference conversion ratios between exponent bases. The tables are characterized by bi-uniform spacings of source and target exponents and including near-unity table entries representing the conversion ratios. A source number is converted into a target number in a different radix by a sequence of reduction operations using a sequence of the tables. The reduction operations include reducing a source number exponent magnitude and accumulating a target exponent and multiplying a source number mantissa by a selected conversion ratio including a near-unity ratio of powers. A final mantissa is normalized and rounded to produce the target number in a new radix.
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International Business Machines - Corporation
Malzahn David H
Stock William J.
Tutunjian & Bitetto, P.C.
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