【 MATLAB 】eps （浮點相對精度）簡介
目錄
eps
Floating-point relative accuracy
Syntax
d = eps
d = eps(x)
d = eps(datatype)
Description
d = eps returns the distance from 1.0 to the next larger double-precision number, that is,
d = eps返回從1.0到下一個更大的雙精度數的距離，即。
d = eps(, where x)x has data type single or double, returns the positive distance from abs(x) to the next larger floating-point number of the same precision as x. If x has typeduration, then eps(x) returns the next larger duration
eps(1.0) is equivalent to eps.
d = eps（x），其中x具有資料型別single或double，返回從abs（x）到下一個與x相同精度的較大浮點數的正距離。 如果x具有typeduration，則eps（x）返回下一個更大的持續時間值。 命令eps（1.0）等同於eps。
d = eps( returns datatype)eps according to the data type specified by datatype, which can be either 'double'
'single'. The syntax eps('double') (default) is equivalent to eps, and eps('single') is equivalent to eps(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））。
Accuracy in Double Precision
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
Accuracy in Single Precision
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
-23
d =
single
9.5367e-07