diff options
Diffstat (limited to 'libstdc++-v3/doc/html/manual/numerics_and_c.html')
| -rw-r--r-- | libstdc++-v3/doc/html/manual/numerics_and_c.html | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/libstdc++-v3/doc/html/manual/numerics_and_c.html b/libstdc++-v3/doc/html/manual/numerics_and_c.html new file mode 100644 index 000000000..3a2fb499e --- /dev/null +++ b/libstdc++-v3/doc/html/manual/numerics_and_c.html @@ -0,0 +1,37 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml"><head><title>Interacting with C</title><meta name="generator" content="DocBook XSL-NS Stylesheets V1.76.1"/><meta name="keywords" content=" ISO C++ , library "/><link rel="home" href="../spine.html" title="The GNU C++ Library"/><link rel="up" href="numerics.html" title="Chapter 12. Numerics"/><link rel="prev" href="generalized_numeric_operations.html" title="Generalized Operations"/><link rel="next" href="io.html" title="Chapter 13. Input and Output"/></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Interacting with C</th></tr><tr><td align="left"><a accesskey="p" href="generalized_numeric_operations.html">Prev</a> </td><th width="60%" align="center">Chapter 12. + Numerics + +</th><td align="right"> <a accesskey="n" href="io.html">Next</a></td></tr></table><hr/></div><div class="section" title="Interacting with C"><div class="titlepage"><div><div><h2 class="title"><a id="std.numerics.c"/>Interacting with C</h2></div></div></div><div class="section" title="Numerics vs. Arrays"><div class="titlepage"><div><div><h3 class="title"><a id="numerics.c.array"/>Numerics vs. Arrays</h3></div></div></div><p>One of the major reasons why FORTRAN can chew through numbers so well + is that it is defined to be free of pointer aliasing, an assumption + that C89 is not allowed to make, and neither is C++98. C99 adds a new + keyword, <code class="code">restrict</code>, to apply to individual pointers. The + C++ solution is contained in the library rather than the language + (although many vendors can be expected to add this to their compilers + as an extension). + </p><p>That library solution is a set of two classes, five template classes, + and "a whole bunch" of functions. The classes are required + to be free of pointer aliasing, so compilers can optimize the + daylights out of them the same way that they have been for FORTRAN. + They are collectively called <code class="code">valarray</code>, although strictly + speaking this is only one of the five template classes, and they are + designed to be familiar to people who have worked with the BLAS + libraries before. + </p></div><div class="section" title="C99"><div class="titlepage"><div><div><h3 class="title"><a id="numerics.c.c99"/>C99</h3></div></div></div><p>In addition to the other topics on this page, we'll note here some + of the C99 features that appear in libstdc++. + </p><p>The C99 features depend on the <code class="code">--enable-c99</code> configure flag. + This flag is already on by default, but it can be disabled by the + user. Also, the configuration machinery will disable it if the + necessary support for C99 (e.g., header files) cannot be found. + </p><p>As of GCC 3.0, C99 support includes classification functions + such as <code class="code">isnormal</code>, <code class="code">isgreater</code>, + <code class="code">isnan</code>, etc. + The functions used for 'long long' support such as <code class="code">strtoll</code> + are supported, as is the <code class="code">lldiv_t</code> typedef. Also supported + are the wide character functions using 'long long', like + <code class="code">wcstoll</code>. + </p></div></div><div class="navfooter"><hr/><table width="100%" summary="Navigation footer"><tr><td align="left"><a accesskey="p" href="generalized_numeric_operations.html">Prev</a> </td><td align="center"><a accesskey="u" href="numerics.html">Up</a></td><td align="right"> <a accesskey="n" href="io.html">Next</a></td></tr><tr><td align="left" valign="top">Generalized Operations </td><td align="center"><a accesskey="h" href="../spine.html">Home</a></td><td align="right" valign="top"> Chapter 13. + Input and Output + +</td></tr></table></div></body></html> |