function?[sef]?=?ieee754（xfmt）
%IEEE754?Decompose?a?double?precision?floating?point?number.
%?[SEF]?=?IEEE754（X）?returns?the?sign?bit?exponent?and?mantissa?of?an
%?IEEE?754?floating?point?value?X?expressed?as?binary?digit?strings?of
%?length?1?11?and?52?respectively.?
%
%?S?=?IEEE754（X）?returns?one?string?of?length?64.
%
%?[SEF]?=?IEEE754（X‘dec‘）?returns?S?E?and?F?as?floating-point?numbers.
%
%?X?is?equal?to?（in?exact?arithmetic?and?decimal?notation）
%
%??????（-1）^S?*?（1?+?F/（2^52））?*??2^（E-1023）
%
%?except?for?special?values?0?Inf?NaN?and?denormalized?numbers?（between
%?0?and?REALMIN）.?
%
%?See?also?FORMAT?REALMAX?REALMIN?BIN2DEC.

%?Copyright?2009?by?Toby?Driscoll?（driscoll@udel.edu）.?
%?Thanks?to?Andreas?Luettgens?for?the?suggestion?of?NUM2HEX.

if?~isreal（x）?||?numel（x）?>?1?||?~isa（x‘double‘）
??error（‘Real?scalar?double?input?required.‘）
end
hex?=?num2hex（x）;????????%?string?of?16?hex?digits?for?x
dec?=?hex2dec（hex‘）;?????%?decimal?for?each?digit?（1?per?row）
bin?=?dec2bin（dec4）;????%?4?binary?digits?per?row
bitstr?=?reshape（bin‘[1?64]）;??%?string?of?64?bits?in?order

%?Return?options
if?nargout<2
??s?=?bitstr;??????
else
??s?=?bitstr（1）;
??e?=?bitstr（2:12）;
??f?=?bitstr（13:64）;
??if?nargin?>?1?&&?isequal（lower（fmt）‘dec‘）
????s?=?bin2dec（s）;??e?=?bin2dec（e）;??f?=?bin2dec（f）;
??end
end

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????1337??2013-10-30?20:41??ieee754.m
?????文件????????1314??2014-02-12?14:37??license.txt