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<p class="MsoNormal"><span lang="EN-US">IMHO, ceil/floor should return integers when we have big-integers. In C, to avoid overflow, they have to return floating point numbers.</span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">IMHO, I don’t think we need ffloor/fround.
</span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Mathematica can be taken as an example.</span></p>
<p class="MsoNormal"><span lang="EN-US"></span></p>
<p class="MsoNormal"><span lang="EN-US">Best regards,<br>
Li Zhengji</span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;font-family:SimSun"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="border:none;padding:0cm"><b>发件人<span lang="EN-US">: </span>
</b><span lang="EN-US"><a href="mailto:ok@cs.otago.ac.nz">Richard A. O'Keefe</a><br>
</span><b>发送时间<span lang="EN-US">: </span></b><span lang="EN-US">2016</span>年<span lang="EN-US">6</span>月<span lang="EN-US">3</span>日<span lang="EN-US"> 11:36<br>
</span><b>收件人<span lang="EN-US">: </span></b><span lang="EN-US"><a href="mailto:erlang-questions@erlang.org">erlang-questions@erlang.org</a><br>
</span><b>主题<span lang="EN-US">: </span></b><span lang="EN-US">Re: [erlang-questions] math ceil floor</span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;font-family:SimSun"><o:p> </o:p></span></p>
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<br>
On 3/06/16 10:42 AM, Technion wrote:<br>
><br>
> Following from other languages, C's ceil returns floats, but Ruby's <br>
> ceil returns an Integer, PHP returns a float.<br>
><br>
><br>
> I'm seeing here there isn't a particularly accepted standard.<br>
><br>
<br>
Let's put that another way.<br>
C's library is defective in only offering truncation to integer (via (int))<br>
and rounding (via l[l]rint{f,,l}()), no int-valued floor or ceiling.<br>
Ruby's Float class is defective in only offering conversion to integer,<br>
not float-valued ceiling &c (Float.round can be persuaded to return a<br>
float, but not when you want it to be integral, which is both absurd and<br>
painfully typical of Ruby).<br>
PHP is, well, PHP.<br>
<br>
If, on the other hand, we turn to other languages,<br>
we learn that Lisp has {f,}(round,floor,ceiling,truncate)<br>
and ML has realFloor, realCeil, realTrunc, realRound and<br>
floor, ceil, trunc, round, 8 functions, not 4.<br>
(The REAL signature, section 11.50 of The Standard<br>
ML Basis Library.)<br>
<br>
So there is prior art for providing *both*, with the simple name<br>
delivering an integer, and the prefixed name returning float.<br>
<br>
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