“cancellation”的概念、定义、翻译、参考文献-科学参考

cancellation

Computer

The loss of significant digits in subtracting two approximately equal numbers. This is a frequent cause of poor accuracy in numerical results but it can usually be avoided by some reorganization of the calculation. Consider, for example, the quadratic equation
$a x^{2} + b x + c = 0$
The formula for the roots of a quadratic is
$(- b \pm \sqrt (b^{2} - 4 a c)) / 2 a$
if b² is large compared with 4|ac| severe cancellation occurs in one of the roots. This root can be computed from the fact that the product of the roots is c/a.

单词	cancellation
释义	cancellation Computer The loss of significant digits in subtracting two approximately equal numbers. This is a frequent cause of poor accuracy in numerical results but it can usually be avoided by some reorganization of the calculation. Consider, for example, the quadratic equation $a x^{2} + b x + c = 0$ The formula for the roots of a quadratic is $(- b \pm \sqrt (b^{2} - 4 a c)) / 2 a$ if b² is large compared with 4\|ac\| severe cancellation occurs in one of the roots. This root can be computed from the fact that the product of the roots is c/a.
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