## Underflow Revisited (1999)

Citations: | 1 - 0 self |

### BibTeX

@MISC{Cuyt99underflowrevisited,

author = {Annie Cuyt and Peter Kuterna and Brigitte Verdonk and Dennis Verschaeren},

title = {Underflow Revisited},

year = {1999}

}

### OpenURL

### Abstract

Underflow is a floating-point phenomenon. Although the use of gradual underflow as defended in [2] and [5] is now widespread, most numerical analysts may not be aware of the fact that several implementations of the same principle are in existence, leading to different behaviour of code on different platforms, mainly with respect to exception signaling. We intend to thoroughly discuss the slight differences among these implementations. Examples will be taken from current hardware and from our own multiprecision software class library. Throughout the discussion the focus is on the analysis of the phenomenon and not on any implementation issues. Many programmers are also unaware of the fact that the IEEE 754 and 854 standards do not guarantee that a program will deliver identical results on all conforming systems. Of all the differences that can occur cross-platform, the underflow exception is just one. ? Research Director FWO-Vlaanderen ffl Supported by an NOI-grant from the Universi...

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Citation Context ...erg@uia.ua.ac.be Keywords Computer arithmetic, IEEE floating-point, underflow exception Abstract Underflow is a floating-point phenomenon. Although the use of gradual underflow as defended in [2] and =-=[5]-=- is now widespread, most numerical analysts may not be aware of the fact that several implementations of the same principle are in existence, leading to different behaviour of code on different platfo... |

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Citation Context ...k, vschaerg@uia.ua.ac.be Keywords Computer arithmetic, IEEE floating-point, underflow exception Abstract Underflow is a floating-point phenomenon. Although the use of gradual underflow as defended in =-=[2]-=- and [5] is now widespread, most numerical analysts may not be aware of the fact that several implementations of the same principle are in existence, leading to different behaviour of code on differen... |

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Citation Context ...onsistency of each implementation was tested using a large set of test vectors which is a generalization of Coonen's [3] and Hough's [7] sets of test vectors and which will be publicly available soon =-=[4]-=-. For each of the precisions (single, double, 64 bit extended on INTEL and 113 bit quadruple on SUN) our test set for multiplication contained 1152 cases of U underflow, an extra 176 cases of V:U unde... |

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Citation Context ...ped by one of the authors, which supports a U implementation. The consistency of each implementation was tested using a large set of test vectors which is a generalization of Coonen's [3] and Hough's =-=[7]-=- sets of test vectors and which will be publicly available soon [4]. For each of the precisions (single, double, 64 bit extended on INTEL and 113 bit quadruple on SUN) our test set for multiplication ... |

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1 |
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