目錄
epssyntax
description
accuracy in double precision
accuracy in single precision
floating-point relative accuracy
d = eps
d = eps(x)
d = eps(datatype)
d = eps
returns the distance from1.0
to the next larger double-precision number, that is,
d = eps返回從1.0到下乙個更大的雙精度數的距離,即
d = eps(x
), wherex
has data typesingle
ordouble
, returns the positive distance fromabs(x)
to the next larger floating-point number of the same precision asx
. ifx
has typeduration
, theneps(x)
returns the next largerduration
value. the commandeps(1.0)
is equivalent toeps
.
d = eps(x),其中x具有資料型別single或double,返回從abs(x)到下乙個與x相同精度的較大浮點數的正距離。 如果x具有typeduration,則eps(x)返回下乙個更大的持續時間值。 命令eps(1.0)等同於eps。
d = eps(datatype
) returnseps
according to the data type specified bydatatype
, which can be either'double'
or'single'
. the syntaxeps('double')
(default) is equivalent toeps
, andeps('single')
is equivalent toeps(single(1.0))
.
d = eps(datatype)根據datatype指定的資料型別返回eps,資料型別可以是「double」或「single」。 語法eps('double')(預設)等同於eps,eps('single')等同於eps(single(1.0))。
clc
clear
close all
% display the distance from 1.0 to the next largest double-precision number.
d = eps
% d = 2.2204e-16
% eps is equivalent to eps(1.0) and eps('double').
% compute log2(eps).
d = log2(eps)
% d = -52
% in base 2, eps is equal to 2^-52.
% % find the distance from 10.0 to the next largest double-precision number.
d = eps(10.0)
% d = 1.7764e-15
結果如下:
d =2.2204e-16
d =-52
d =1.7764e-15
clc
clear
close all
% display the distance from 1.0 to the next largest single-precision number.
d = eps('single')
% d = single
% 1.1921e-07
% eps('single') is equivalent to eps(single(1.0)).
% compute log2(eps('single')).
d = log2(eps('single'))
% d = single
% -23
% in base 2, single-precision eps is equal to 2^-23.
% find the distance from the single-precision representation of 10.0 to the next largest single-precision number.
d = eps(single(10.0))
% d = single
% 9.5367e-07
結果如下:
d =single
1.1921e-07
d =single
-23d =
single
9.5367e-07
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