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<h1>src/libsphinxbase/util/logmath.c</h1> </div>
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<div class="contents">
<div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */</span>
<a name="l00002"></a>00002 <span class="comment">/* ====================================================================</span>
<a name="l00003"></a>00003 <span class="comment"> * Copyright (c) 1999-2007 Carnegie Mellon University. All rights</span>
<a name="l00004"></a>00004 <span class="comment"> * reserved.</span>
<a name="l00005"></a>00005 <span class="comment"> *</span>
<a name="l00006"></a>00006 <span class="comment"> * Redistribution and use in source and binary forms, with or without</span>
<a name="l00007"></a>00007 <span class="comment"> * modification, are permitted provided that the following conditions</span>
<a name="l00008"></a>00008 <span class="comment"> * are met:</span>
<a name="l00009"></a>00009 <span class="comment"> *</span>
<a name="l00010"></a>00010 <span class="comment"> * 1. Redistributions of source code must retain the above copyright</span>
<a name="l00011"></a>00011 <span class="comment"> * notice, this list of conditions and the following disclaimer. </span>
<a name="l00012"></a>00012 <span class="comment"> *</span>
<a name="l00013"></a>00013 <span class="comment"> * 2. Redistributions in binary form must reproduce the above copyright</span>
<a name="l00014"></a>00014 <span class="comment"> * notice, this list of conditions and the following disclaimer in</span>
<a name="l00015"></a>00015 <span class="comment"> * the documentation and/or other materials provided with the</span>
<a name="l00016"></a>00016 <span class="comment"> * distribution.</span>
<a name="l00017"></a>00017 <span class="comment"> *</span>
<a name="l00018"></a>00018 <span class="comment"> * This work was supported in part by funding from the Defense Advanced </span>
<a name="l00019"></a>00019 <span class="comment"> * Research Projects Agency and the National Science Foundation of the </span>
<a name="l00020"></a>00020 <span class="comment"> * United States of America, and the CMU Sphinx Speech Consortium.</span>
<a name="l00021"></a>00021 <span class="comment"> *</span>
<a name="l00022"></a>00022 <span class="comment"> * THIS SOFTWARE IS PROVIDED BY CARNEGIE MELLON UNIVERSITY ``AS IS'' AND </span>
<a name="l00023"></a>00023 <span class="comment"> * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, </span>
<a name="l00024"></a>00024 <span class="comment"> * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR</span>
<a name="l00025"></a>00025 <span class="comment"> * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY</span>
<a name="l00026"></a>00026 <span class="comment"> * NOR ITS EMPLOYEES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,</span>
<a name="l00027"></a>00027 <span class="comment"> * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT </span>
<a name="l00028"></a>00028 <span class="comment"> * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, </span>
<a name="l00029"></a>00029 <span class="comment"> * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY </span>
<a name="l00030"></a>00030 <span class="comment"> * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT </span>
<a name="l00031"></a>00031 <span class="comment"> * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE </span>
<a name="l00032"></a>00032 <span class="comment"> * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.</span>
<a name="l00033"></a>00033 <span class="comment"> *</span>
<a name="l00034"></a>00034 <span class="comment"> * ====================================================================</span>
<a name="l00035"></a>00035 <span class="comment"> *</span>
<a name="l00036"></a>00036 <span class="comment"> */</span>
<a name="l00037"></a>00037
<a name="l00038"></a>00038 <span class="preprocessor">#include <math.h></span>
<a name="l00039"></a>00039 <span class="preprocessor">#include <string.h></span>
<a name="l00040"></a>00040 <span class="preprocessor">#include <assert.h></span>
<a name="l00041"></a>00041
<a name="l00042"></a>00042 <span class="preprocessor">#include "sphinxbase/logmath.h"</span>
<a name="l00043"></a>00043 <span class="preprocessor">#include "sphinxbase/err.h"</span>
<a name="l00044"></a>00044 <span class="preprocessor">#include "sphinxbase/ckd_alloc.h"</span>
<a name="l00045"></a>00045 <span class="preprocessor">#include "sphinxbase/mmio.h"</span>
<a name="l00046"></a>00046 <span class="preprocessor">#include "sphinxbase/bio.h"</span>
<a name="l00047"></a>00047 <span class="preprocessor">#include "sphinxbase/strfuncs.h"</span>
<a name="l00048"></a>00048
<a name="l00049"></a><a class="code" href="structlogmath__s.html">00049</a> <span class="keyword">struct </span><a class="code" href="structlogmath__s.html">logmath_s</a> {
<a name="l00050"></a>00050 <a class="code" href="structlogadd__s.html">logadd_t</a> t;
<a name="l00051"></a>00051 <span class="keywordtype">int</span> refcount;
<a name="l00052"></a>00052 <a class="code" href="structmmio__file__s.html" title="Silvio Moioli: slightly updated.">mmio_file_t</a> *filemap;
<a name="l00053"></a>00053 float64 base;
<a name="l00054"></a>00054 float64 log_of_base;
<a name="l00055"></a>00055 float64 log10_of_base;
<a name="l00056"></a>00056 float64 inv_log_of_base;
<a name="l00057"></a>00057 float64 inv_log10_of_base;
<a name="l00058"></a>00058 int32 zero;
<a name="l00059"></a>00059 };
<a name="l00060"></a>00060
<a name="l00061"></a>00061 <a class="code" href="structlogmath__s.html">logmath_t</a> *
<a name="l00062"></a><a class="code" href="logmath_8h.html#a5835860c5f6a703c80c0214f816f0b11">00062</a> <a class="code" href="logmath_8h.html#a5835860c5f6a703c80c0214f816f0b11" title="Initialize a log math computation table.">logmath_init</a>(float64 base, <span class="keywordtype">int</span> shift, <span class="keywordtype">int</span> use_table)
<a name="l00063"></a>00063 {
<a name="l00064"></a>00064 <a class="code" href="structlogmath__s.html">logmath_t</a> *lmath;
<a name="l00065"></a>00065 uint32 maxyx, i;
<a name="l00066"></a>00066 float64 byx;
<a name="l00067"></a>00067 <span class="keywordtype">int</span> width;
<a name="l00068"></a>00068
<a name="l00069"></a>00069 <span class="comment">/* Check that the base is correct. */</span>
<a name="l00070"></a>00070 <span class="keywordflow">if</span> (base <= 1.0) {
<a name="l00071"></a>00071 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"Base must be greater than 1.0\n"</span>);
<a name="l00072"></a>00072 <span class="keywordflow">return</span> NULL;
<a name="l00073"></a>00073 }
<a name="l00074"></a>00074
<a name="l00075"></a>00075 <span class="comment">/* Set up various necessary constants. */</span>
<a name="l00076"></a>00076 lmath = <a class="code" href="ckd__alloc_8h.html#aa00ef21903bc4f8a972488417adc8d2e" title="Macros to simplify the use of above functions.">ckd_calloc</a>(1, <span class="keyword">sizeof</span>(*lmath));
<a name="l00077"></a>00077 lmath->refcount = 1;
<a name="l00078"></a>00078 lmath->base = base;
<a name="l00079"></a>00079 lmath->log_of_base = log(base);
<a name="l00080"></a>00080 lmath->log10_of_base = log10(base);
<a name="l00081"></a>00081 lmath->inv_log_of_base = 1.0/lmath->log_of_base;
<a name="l00082"></a>00082 lmath->inv_log10_of_base = 1.0/lmath->log10_of_base;
<a name="l00083"></a>00083 lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a> = shift;
<a name="l00084"></a>00084 <span class="comment">/* Shift this sufficiently that overflows can be avoided. */</span>
<a name="l00085"></a>00085 lmath->zero = MAX_NEG_INT32 >> (shift + 2);
<a name="l00086"></a>00086
<a name="l00087"></a>00087 <span class="keywordflow">if</span> (!use_table)
<a name="l00088"></a>00088 <span class="keywordflow">return</span> lmath;
<a name="l00089"></a>00089
<a name="l00090"></a>00090 <span class="comment">/* Create a logadd table with the appropriate width */</span>
<a name="l00091"></a>00091 maxyx = (uint32) (log(2.0) / log(base) + 0.5) >> shift;
<a name="l00092"></a>00092 <span class="comment">/* Poor man's log2 */</span>
<a name="l00093"></a>00093 <span class="keywordflow">if</span> (maxyx < 256) width = 1;
<a name="l00094"></a>00094 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (maxyx < 65536) width = 2;
<a name="l00095"></a>00095 <span class="keywordflow">else</span> width = 4;
<a name="l00096"></a>00096
<a name="l00097"></a>00097 lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a> = width;
<a name="l00098"></a>00098 <span class="comment">/* Figure out size of add table required. */</span>
<a name="l00099"></a>00099 byx = 1.0; <span class="comment">/* Maximum possible base^{y-x} value - note that this implies that y-x == 0 */</span>
<a name="l00100"></a>00100 <span class="keywordflow">for</span> (i = 0;; ++i) {
<a name="l00101"></a>00101 float64 lobyx = log(1.0 + byx) * lmath->inv_log_of_base; <span class="comment">/* log_{base}(1 + base^{y-x}); */</span>
<a name="l00102"></a>00102 int32 k = (int32) (lobyx + 0.5 * (1<<shift)) >> shift; <span class="comment">/* Round to shift */</span>
<a name="l00103"></a>00103
<a name="l00104"></a>00104 <span class="comment">/* base^{y-x} has reached the smallest representable value. */</span>
<a name="l00105"></a>00105 <span class="keywordflow">if</span> (k <= 0)
<a name="l00106"></a>00106 <span class="keywordflow">break</span>;
<a name="l00107"></a>00107
<a name="l00108"></a>00108 <span class="comment">/* This table is indexed by -(y-x), so we multiply byx by</span>
<a name="l00109"></a>00109 <span class="comment"> * base^{-1} here which is equivalent to subtracting one from</span>
<a name="l00110"></a>00110 <span class="comment"> * (y-x). */</span>
<a name="l00111"></a>00111 byx /= base;
<a name="l00112"></a>00112 }
<a name="l00113"></a>00113 i >>= shift;
<a name="l00114"></a>00114
<a name="l00115"></a>00115 <span class="comment">/* Never produce a table smaller than 256 entries. */</span>
<a name="l00116"></a>00116 <span class="keywordflow">if</span> (i < 255) i = 255;
<a name="l00117"></a>00117
<a name="l00118"></a>00118 lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a> = <a class="code" href="ckd__alloc_8h.html#aa00ef21903bc4f8a972488417adc8d2e" title="Macros to simplify the use of above functions.">ckd_calloc</a>(i+1, width);
<a name="l00119"></a>00119 lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a> = i + 1;
<a name="l00120"></a>00120 <span class="comment">/* Create the add table (see above). */</span>
<a name="l00121"></a>00121 byx = 1.0;
<a name="l00122"></a>00122 <span class="keywordflow">for</span> (i = 0;; ++i) {
<a name="l00123"></a>00123 float64 lobyx = log(1.0 + byx) * lmath->inv_log_of_base;
<a name="l00124"></a>00124 int32 k = (int32) (lobyx + 0.5 * (1<<shift)) >> shift; <span class="comment">/* Round to shift */</span>
<a name="l00125"></a>00125 uint32 prev = 0;
<a name="l00126"></a>00126
<a name="l00127"></a>00127 <span class="comment">/* Check any previous value - if there is a shift, we want to</span>
<a name="l00128"></a>00128 <span class="comment"> * only store the highest one. */</span>
<a name="l00129"></a>00129 <span class="keywordflow">switch</span> (width) {
<a name="l00130"></a>00130 <span class="keywordflow">case</span> 1:
<a name="l00131"></a>00131 prev = ((uint8 *)lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[i >> shift];
<a name="l00132"></a>00132 <span class="keywordflow">break</span>;
<a name="l00133"></a>00133 <span class="keywordflow">case</span> 2:
<a name="l00134"></a>00134 prev = ((uint16 *)lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[i >> shift];
<a name="l00135"></a>00135 <span class="keywordflow">break</span>;
<a name="l00136"></a>00136 <span class="keywordflow">case</span> 4:
<a name="l00137"></a>00137 prev = ((uint32 *)lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[i >> shift];
<a name="l00138"></a>00138 <span class="keywordflow">break</span>;
<a name="l00139"></a>00139 }
<a name="l00140"></a>00140 <span class="keywordflow">if</span> (prev == 0) {
<a name="l00141"></a>00141 <span class="keywordflow">switch</span> (width) {
<a name="l00142"></a>00142 <span class="keywordflow">case</span> 1:
<a name="l00143"></a>00143 ((uint8 *)lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[i >> shift] = (uint8) k;
<a name="l00144"></a>00144 <span class="keywordflow">break</span>;
<a name="l00145"></a>00145 <span class="keywordflow">case</span> 2:
<a name="l00146"></a>00146 ((uint16 *)lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[i >> shift] = (uint16) k;
<a name="l00147"></a>00147 <span class="keywordflow">break</span>;
<a name="l00148"></a>00148 <span class="keywordflow">case</span> 4:
<a name="l00149"></a>00149 ((uint32 *)lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[i >> shift] = (uint32) k;
<a name="l00150"></a>00150 <span class="keywordflow">break</span>;
<a name="l00151"></a>00151 }
<a name="l00152"></a>00152 }
<a name="l00153"></a>00153 <span class="keywordflow">if</span> (k <= 0)
<a name="l00154"></a>00154 <span class="keywordflow">break</span>;
<a name="l00155"></a>00155
<a name="l00156"></a>00156 <span class="comment">/* Decay base^{y-x} exponentially according to base. */</span>
<a name="l00157"></a>00157 byx /= base;
<a name="l00158"></a>00158 }
<a name="l00159"></a>00159
<a name="l00160"></a>00160 <span class="keywordflow">return</span> lmath;
<a name="l00161"></a>00161 }
<a name="l00162"></a>00162
<a name="l00163"></a>00163 <a class="code" href="structlogmath__s.html">logmath_t</a> *
<a name="l00164"></a><a class="code" href="logmath_8h.html#afbed298ba0bc4736415d78880fe5c7c2">00164</a> <a class="code" href="logmath_8h.html#afbed298ba0bc4736415d78880fe5c7c2" title="Memory-map (or read) a log table from a file.">logmath_read</a>(<span class="keyword">const</span> <span class="keywordtype">char</span> *file_name)
<a name="l00165"></a>00165 {
<a name="l00166"></a>00166 <a class="code" href="structlogmath__s.html">logmath_t</a> *lmath;
<a name="l00167"></a>00167 <span class="keywordtype">char</span> **argname, **argval;
<a name="l00168"></a>00168 int32 byteswap, i;
<a name="l00169"></a>00169 <span class="keywordtype">int</span> chksum_present, do_mmap;
<a name="l00170"></a>00170 uint32 chksum;
<a name="l00171"></a>00171 <span class="keywordtype">long</span> pos;
<a name="l00172"></a>00172 FILE *fp;
<a name="l00173"></a>00173
<a name="l00174"></a>00174 <a class="code" href="err_8h.html#ac3c705943d946708cea0a1443be1c853" title="Print logging information to standard error stream.">E_INFO</a>(<span class="stringliteral">"Reading log table file '%s'\n"</span>, file_name);
<a name="l00175"></a>00175 <span class="keywordflow">if</span> ((fp = fopen(file_name, <span class="stringliteral">"rb"</span>)) == NULL) {
<a name="l00176"></a>00176 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"Failed to open log table file '%s' for reading: %s\n"</span>, file_name, strerror(errno));
<a name="l00177"></a>00177 <span class="keywordflow">return</span> NULL;
<a name="l00178"></a>00178 }
<a name="l00179"></a>00179
<a name="l00180"></a>00180 <span class="comment">/* Read header, including argument-value info and 32-bit byteorder magic */</span>
<a name="l00181"></a>00181 <span class="keywordflow">if</span> (<a class="code" href="bio_8h.html#a7a155ff51740f1d9a31f7bb7b6e4bc3a" title="Read binary file format header: has the following format.">bio_readhdr</a>(fp, &argname, &argval, &byteswap) < 0) {
<a name="l00182"></a>00182 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"bio_readhdr(%s) failed\n"</span>, file_name);
<a name="l00183"></a>00183 fclose(fp);
<a name="l00184"></a>00184 <span class="keywordflow">return</span> NULL;
<a name="l00185"></a>00185 }
<a name="l00186"></a>00186
<a name="l00187"></a>00187 lmath = <a class="code" href="ckd__alloc_8h.html#aa00ef21903bc4f8a972488417adc8d2e" title="Macros to simplify the use of above functions.">ckd_calloc</a>(1, <span class="keyword">sizeof</span>(*lmath));
<a name="l00188"></a>00188 <span class="comment">/* Default values. */</span>
<a name="l00189"></a>00189 lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a> = 0;
<a name="l00190"></a>00190 lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a> = 2;
<a name="l00191"></a>00191 lmath->base = 1.0001;
<a name="l00192"></a>00192
<a name="l00193"></a>00193 <span class="comment">/* Parse argument-value list */</span>
<a name="l00194"></a>00194 chksum_present = 0;
<a name="l00195"></a>00195 <span class="keywordflow">for</span> (i = 0; argname[i]; i++) {
<a name="l00196"></a>00196 <span class="keywordflow">if</span> (strcmp(argname[i], <span class="stringliteral">"version"</span>) == 0) {
<a name="l00197"></a>00197 }
<a name="l00198"></a>00198 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (strcmp(argname[i], <span class="stringliteral">"chksum0"</span>) == 0) {
<a name="l00199"></a>00199 <span class="keywordflow">if</span> (strcmp(argval[i], <span class="stringliteral">"yes"</span>) == 0)
<a name="l00200"></a>00200 chksum_present = 1;
<a name="l00201"></a>00201 }
<a name="l00202"></a>00202 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (strcmp(argname[i], <span class="stringliteral">"width"</span>) == 0) {
<a name="l00203"></a>00203 lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a> = atoi(argval[i]);
<a name="l00204"></a>00204 }
<a name="l00205"></a>00205 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (strcmp(argname[i], <span class="stringliteral">"shift"</span>) == 0) {
<a name="l00206"></a>00206 lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a> = atoi(argval[i]);
<a name="l00207"></a>00207 }
<a name="l00208"></a>00208 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (strcmp(argname[i], <span class="stringliteral">"logbase"</span>) == 0) {
<a name="l00209"></a>00209 lmath->base = <a class="code" href="strfuncs_8h.html#ab708351fe7308551632a782bfad75a1e" title="Locale independent version of atof().">atof_c</a>(argval[i]);
<a name="l00210"></a>00210 }
<a name="l00211"></a>00211 }
<a name="l00212"></a>00212 <a class="code" href="bio_8h.html#adb3c858a50381aeff022ccd4271af2d9" title="Free name and value strings previously allocated and returned by bio_readhdr.">bio_hdrarg_free</a>(argname, argval);
<a name="l00213"></a>00213 chksum = 0;
<a name="l00214"></a>00214
<a name="l00215"></a>00215 <span class="comment">/* Set up various necessary constants. */</span>
<a name="l00216"></a>00216 lmath->log_of_base = log(lmath->base);
<a name="l00217"></a>00217 lmath->log10_of_base = log10(lmath->base);
<a name="l00218"></a>00218 lmath->inv_log_of_base = 1.0/lmath->log_of_base;
<a name="l00219"></a>00219 lmath->inv_log10_of_base = 1.0/lmath->log10_of_base;
<a name="l00220"></a>00220 <span class="comment">/* Shift this sufficiently that overflows can be avoided. */</span>
<a name="l00221"></a>00221 lmath->zero = MAX_NEG_INT32 >> (lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a> + 2);
<a name="l00222"></a>00222
<a name="l00223"></a>00223 <span class="comment">/* #Values to follow */</span>
<a name="l00224"></a>00224 <span class="keywordflow">if</span> (<a class="code" href="bio_8h.html#a7068bb61e421bc46a6989cef3b37c833" title="Like fread but perform byteswapping and accumulate checksum (the 2 extra arguments).">bio_fread</a>(&lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>, <span class="keyword">sizeof</span>(int32), 1, fp, byteswap, &chksum) != 1) {
<a name="l00225"></a>00225 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"fread(%s) (total #values) failed\n"</span>, file_name);
<a name="l00226"></a>00226 <span class="keywordflow">goto</span> error_out;
<a name="l00227"></a>00227 }
<a name="l00228"></a>00228
<a name="l00229"></a>00229 <span class="comment">/* Check alignment constraints for memory mapping */</span>
<a name="l00230"></a>00230 do_mmap = 1;
<a name="l00231"></a>00231 pos = ftell(fp);
<a name="l00232"></a>00232 <span class="keywordflow">if</span> (pos & ((<span class="keywordtype">long</span>)lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a> - 1)) {
<a name="l00233"></a>00233 <a class="code" href="err_8h.html#a6a794bec721b555ac1f2167f9e12f662" title="Print warning information to standard error stream.">E_WARN</a>(<span class="stringliteral">"%s: Data start %ld is not aligned on %d-byte boundary, will not memory map\n"</span>,
<a name="l00234"></a>00234 file_name, pos, lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>);
<a name="l00235"></a>00235 do_mmap = 0;
<a name="l00236"></a>00236 }
<a name="l00237"></a>00237 <span class="comment">/* Check byte order for memory mapping */</span>
<a name="l00238"></a>00238 <span class="keywordflow">if</span> (byteswap) {
<a name="l00239"></a>00239 <a class="code" href="err_8h.html#a6a794bec721b555ac1f2167f9e12f662" title="Print warning information to standard error stream.">E_WARN</a>(<span class="stringliteral">"%s: Data is wrong-endian, will not memory map\n"</span>, file_name);
<a name="l00240"></a>00240 do_mmap = 0;
<a name="l00241"></a>00241 }
<a name="l00242"></a>00242
<a name="l00243"></a>00243 <span class="keywordflow">if</span> (do_mmap) {
<a name="l00244"></a>00244 lmath->filemap = <a class="code" href="mmio_8h.html#ae3367a51a50a6108178ecfdd6c983c61" title="Memory-map a file for reading.">mmio_file_read</a>(file_name);
<a name="l00245"></a>00245 lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a> = (<span class="keywordtype">char</span> *)<a class="code" href="mmio_8h.html#a5e6d8bf5cd7785563abc18c70a31ce0d" title="Get a pointer to the memory mapped for a file.">mmio_file_ptr</a>(lmath->filemap) + pos;
<a name="l00246"></a>00246 }
<a name="l00247"></a>00247 <span class="keywordflow">else</span> {
<a name="l00248"></a>00248 lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a> = <a class="code" href="ckd__alloc_8h.html#aa00ef21903bc4f8a972488417adc8d2e" title="Macros to simplify the use of above functions.">ckd_calloc</a>(lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>, lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>);
<a name="l00249"></a>00249 <span class="keywordflow">if</span> (<a class="code" href="bio_8h.html#a7068bb61e421bc46a6989cef3b37c833" title="Like fread but perform byteswapping and accumulate checksum (the 2 extra arguments).">bio_fread</a>(lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>, lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>, lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>,
<a name="l00250"></a>00250 fp, byteswap, &chksum) != lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>) {
<a name="l00251"></a>00251 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"fread(%s) (%d x %d bytes) failed\n"</span>,
<a name="l00252"></a>00252 file_name, lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>, lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>);
<a name="l00253"></a>00253 <span class="keywordflow">goto</span> error_out;
<a name="l00254"></a>00254 }
<a name="l00255"></a>00255 <span class="keywordflow">if</span> (chksum_present)
<a name="l00256"></a>00256 <a class="code" href="bio_8h.html#ad07e2ee9f2f01d3ff3232008098295a0" title="Read and verify checksum at the end of binary file.">bio_verify_chksum</a>(fp, byteswap, chksum);
<a name="l00257"></a>00257
<a name="l00258"></a>00258 <span class="keywordflow">if</span> (fread(&i, 1, 1, fp) == 1) {
<a name="l00259"></a>00259 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"%s: More data than expected\n"</span>, file_name);
<a name="l00260"></a>00260 <span class="keywordflow">goto</span> error_out;
<a name="l00261"></a>00261 }
<a name="l00262"></a>00262 }
<a name="l00263"></a>00263 fclose(fp);
<a name="l00264"></a>00264
<a name="l00265"></a>00265 <span class="keywordflow">return</span> lmath;
<a name="l00266"></a>00266 error_out:
<a name="l00267"></a>00267 <a class="code" href="logmath_8h.html#a97865ef8bc1e8e2525a2329e0627ecfb" title="Free a log table.">logmath_free</a>(lmath);
<a name="l00268"></a>00268 <span class="keywordflow">return</span> NULL;
<a name="l00269"></a>00269 }
<a name="l00270"></a>00270
<a name="l00271"></a>00271 int32
<a name="l00272"></a><a class="code" href="logmath_8h.html#a787070f5e689878348ef219245fc7c44">00272</a> <a class="code" href="logmath_8h.html#a787070f5e689878348ef219245fc7c44" title="Write a log table to a file.">logmath_write</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, <span class="keyword">const</span> <span class="keywordtype">char</span> *file_name)
<a name="l00273"></a>00273 {
<a name="l00274"></a>00274 FILE *fp;
<a name="l00275"></a>00275 <span class="keywordtype">long</span> pos;
<a name="l00276"></a>00276 uint32 chksum;
<a name="l00277"></a>00277
<a name="l00278"></a>00278 <span class="keywordflow">if</span> (lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a> == NULL) {
<a name="l00279"></a>00279 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"No log table to write!\n"</span>);
<a name="l00280"></a>00280 <span class="keywordflow">return</span> -1;
<a name="l00281"></a>00281 }
<a name="l00282"></a>00282
<a name="l00283"></a>00283 <a class="code" href="err_8h.html#ac3c705943d946708cea0a1443be1c853" title="Print logging information to standard error stream.">E_INFO</a>(<span class="stringliteral">"Writing log table file '%s'\n"</span>, file_name);
<a name="l00284"></a>00284 <span class="keywordflow">if</span> ((fp = fopen(file_name, <span class="stringliteral">"wb"</span>)) == NULL) {
<a name="l00285"></a>00285 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"Failed to open logtable file '%s' for writing: %s\n"</span>, file_name, strerror(errno));
<a name="l00286"></a>00286 <span class="keywordflow">return</span> -1;
<a name="l00287"></a>00287 }
<a name="l00288"></a>00288
<a name="l00289"></a>00289 <span class="comment">/* For whatever reason, we have to do this manually at the</span>
<a name="l00290"></a>00290 <span class="comment"> * moment. */</span>
<a name="l00291"></a>00291 fprintf(fp, <span class="stringliteral">"s3\nversion 1.0\nchksum0 yes\n"</span>);
<a name="l00292"></a>00292 fprintf(fp, <span class="stringliteral">"width %d\n"</span>, lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>);
<a name="l00293"></a>00293 fprintf(fp, <span class="stringliteral">"shift %d\n"</span>, lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>);
<a name="l00294"></a>00294 fprintf(fp, <span class="stringliteral">"logbase %f\n"</span>, lmath->base);
<a name="l00295"></a>00295 <span class="comment">/* Pad it out to ensure alignment. */</span>
<a name="l00296"></a>00296 pos = ftell(fp) + strlen(<span class="stringliteral">"endhdr\n"</span>);
<a name="l00297"></a>00297 <span class="keywordflow">if</span> (pos & ((<span class="keywordtype">long</span>)lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a> - 1)) {
<a name="l00298"></a>00298 <span class="keywordtype">size_t</span> align = lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a> - (pos & ((long)lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a> - 1));
<a name="l00299"></a>00299 assert(lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a> <= 8);
<a name="l00300"></a>00300 fwrite(<span class="stringliteral">" "</span> <span class="comment">/* 8 spaces */</span>, 1, align, fp);
<a name="l00301"></a>00301 }
<a name="l00302"></a>00302 fprintf(fp, <span class="stringliteral">"endhdr\n"</span>);
<a name="l00303"></a>00303
<a name="l00304"></a>00304 <span class="comment">/* Now write the binary data. */</span>
<a name="l00305"></a>00305 chksum = (uint32)BYTE_ORDER_MAGIC;
<a name="l00306"></a>00306 fwrite(&chksum, <span class="keyword">sizeof</span>(uint32), 1, fp);
<a name="l00307"></a>00307 chksum = 0;
<a name="l00308"></a>00308 <span class="comment">/* #Values to follow */</span>
<a name="l00309"></a>00309 <span class="keywordflow">if</span> (<a class="code" href="bio_8h.html#a3b131beb20492e1a6f46c9b4dd81a64e" title="Like fwrite but perform byteswapping and accumulate checksum (the 2 extra arguments).">bio_fwrite</a>(&lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>, <span class="keyword">sizeof</span>(uint32),
<a name="l00310"></a>00310 1, fp, 0, &chksum) != 1) {
<a name="l00311"></a>00311 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"fwrite(%s) (total #values) failed\n"</span>, file_name);
<a name="l00312"></a>00312 <span class="keywordflow">goto</span> error_out;
<a name="l00313"></a>00313 }
<a name="l00314"></a>00314
<a name="l00315"></a>00315 <span class="keywordflow">if</span> (<a class="code" href="bio_8h.html#a3b131beb20492e1a6f46c9b4dd81a64e" title="Like fwrite but perform byteswapping and accumulate checksum (the 2 extra arguments).">bio_fwrite</a>(lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>, lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>, lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>,
<a name="l00316"></a>00316 fp, 0, &chksum) != lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>) {
<a name="l00317"></a>00317 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"fwrite(%s) (%d x %d bytes) failed\n"</span>,
<a name="l00318"></a>00318 file_name, lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>, lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>);
<a name="l00319"></a>00319 <span class="keywordflow">goto</span> error_out;
<a name="l00320"></a>00320 }
<a name="l00321"></a>00321 <span class="keywordflow">if</span> (<a class="code" href="bio_8h.html#a3b131beb20492e1a6f46c9b4dd81a64e" title="Like fwrite but perform byteswapping and accumulate checksum (the 2 extra arguments).">bio_fwrite</a>(&chksum, <span class="keyword">sizeof</span>(uint32), 1, fp, 0, NULL) != 1) {
<a name="l00322"></a>00322 <a class="code" href="err_8h.html#a5f7b2f58f5a663a6bdd51f197ae21993" title="Print error message to standard error stream.">E_ERROR</a>(<span class="stringliteral">"fwrite(%s) checksum failed\n"</span>, file_name);
<a name="l00323"></a>00323 <span class="keywordflow">goto</span> error_out;
<a name="l00324"></a>00324 }
<a name="l00325"></a>00325
<a name="l00326"></a>00326 fclose(fp);
<a name="l00327"></a>00327 <span class="keywordflow">return</span> 0;
<a name="l00328"></a>00328
<a name="l00329"></a>00329 error_out:
<a name="l00330"></a>00330 fclose(fp);
<a name="l00331"></a>00331 <span class="keywordflow">return</span> -1;
<a name="l00332"></a>00332 }
<a name="l00333"></a>00333
<a name="l00334"></a>00334 <a class="code" href="structlogmath__s.html">logmath_t</a> *
<a name="l00335"></a><a class="code" href="logmath_8h.html#a1c1b2ba3b137a39e9e835a8f3e27d381">00335</a> <a class="code" href="logmath_8h.html#a1c1b2ba3b137a39e9e835a8f3e27d381" title="Retain ownership of a log table.">logmath_retain</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath)
<a name="l00336"></a>00336 {
<a name="l00337"></a>00337 ++lmath->refcount;
<a name="l00338"></a>00338 <span class="keywordflow">return</span> lmath;
<a name="l00339"></a>00339 }
<a name="l00340"></a>00340
<a name="l00341"></a>00341 <span class="keywordtype">int</span>
<a name="l00342"></a><a class="code" href="logmath_8h.html#a97865ef8bc1e8e2525a2329e0627ecfb">00342</a> <a class="code" href="logmath_8h.html#a97865ef8bc1e8e2525a2329e0627ecfb" title="Free a log table.">logmath_free</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath)
<a name="l00343"></a>00343 {
<a name="l00344"></a>00344 <span class="keywordflow">if</span> (lmath == NULL)
<a name="l00345"></a>00345 <span class="keywordflow">return</span> 0;
<a name="l00346"></a>00346 <span class="keywordflow">if</span> (--lmath->refcount > 0)
<a name="l00347"></a>00347 <span class="keywordflow">return</span> lmath->refcount;
<a name="l00348"></a>00348 <span class="keywordflow">if</span> (lmath->filemap)
<a name="l00349"></a>00349 <a class="code" href="mmio_8h.html#a341a9c1cc8a3c4bddfd2d29a1b0993f6" title="Unmap a file, releasing memory associated with it.">mmio_file_unmap</a>(lmath->filemap);
<a name="l00350"></a>00350 <span class="keywordflow">else</span>
<a name="l00351"></a>00351 <a class="code" href="ckd__alloc_8h.html#a31c6b405558620ac37599737b5722fbf" title="Test and free a 1-D array.">ckd_free</a>(lmath->t.<a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>);
<a name="l00352"></a>00352 <a class="code" href="ckd__alloc_8h.html#a31c6b405558620ac37599737b5722fbf" title="Test and free a 1-D array.">ckd_free</a>(lmath);
<a name="l00353"></a>00353 <span class="keywordflow">return</span> 0;
<a name="l00354"></a>00354 }
<a name="l00355"></a>00355
<a name="l00356"></a>00356 int32
<a name="l00357"></a><a class="code" href="logmath_8h.html#a3280500e77bf27aa7cda23268b8eb8b3">00357</a> <a class="code" href="logmath_8h.html#a3280500e77bf27aa7cda23268b8eb8b3" title="Get the log table size and dimensions.">logmath_get_table_shape</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, uint32 *out_size,
<a name="l00358"></a>00358 uint32 *out_width, uint32 *out_shift)
<a name="l00359"></a>00359 {
<a name="l00360"></a>00360 <span class="keywordflow">if</span> (out_size) *out_size = lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>;
<a name="l00361"></a>00361 <span class="keywordflow">if</span> (out_width) *out_width = lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>;
<a name="l00362"></a>00362 <span class="keywordflow">if</span> (out_shift) *out_shift = lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>;
<a name="l00363"></a>00363
<a name="l00364"></a>00364 <span class="keywordflow">return</span> lmath->t.<a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a> * lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>;
<a name="l00365"></a>00365 }
<a name="l00366"></a>00366
<a name="l00367"></a>00367 float64
<a name="l00368"></a><a class="code" href="logmath_8h.html#a6114206ec0321d7015c42fc7b81cb83e">00368</a> <a class="code" href="logmath_8h.html#a6114206ec0321d7015c42fc7b81cb83e" title="Get the log base.">logmath_get_base</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath)
<a name="l00369"></a>00369 {
<a name="l00370"></a>00370 <span class="keywordflow">return</span> lmath->base;
<a name="l00371"></a>00371 }
<a name="l00372"></a>00372
<a name="l00373"></a>00373 <span class="keywordtype">int</span>
<a name="l00374"></a><a class="code" href="logmath_8h.html#a1c160c28a9e7d25923f391773b1028c0">00374</a> <a class="code" href="logmath_8h.html#a1c160c28a9e7d25923f391773b1028c0" title="Get the smallest possible value represented in this base.">logmath_get_zero</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath)
<a name="l00375"></a>00375 {
<a name="l00376"></a>00376 <span class="keywordflow">return</span> lmath->zero;
<a name="l00377"></a>00377 }
<a name="l00378"></a>00378
<a name="l00379"></a>00379 <span class="keywordtype">int</span>
<a name="l00380"></a><a class="code" href="logmath_8h.html#a0cd690d2a414aebb5e126b8cabbfabde">00380</a> <a class="code" href="logmath_8h.html#a0cd690d2a414aebb5e126b8cabbfabde" title="Get the width of the values in a log table.">logmath_get_width</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath)
<a name="l00381"></a>00381 {
<a name="l00382"></a>00382 <span class="keywordflow">return</span> lmath->t.<a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>;
<a name="l00383"></a>00383 }
<a name="l00384"></a>00384
<a name="l00385"></a>00385 <span class="keywordtype">int</span>
<a name="l00386"></a><a class="code" href="logmath_8h.html#aed009aca9736612bebdda57444ec63a6">00386</a> <a class="code" href="logmath_8h.html#aed009aca9736612bebdda57444ec63a6" title="Get the shift of the values in a log table.">logmath_get_shift</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath)
<a name="l00387"></a>00387 {
<a name="l00388"></a>00388 <span class="keywordflow">return</span> lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>;
<a name="l00389"></a>00389 }
<a name="l00390"></a>00390
<a name="l00391"></a>00391 <span class="keywordtype">int</span>
<a name="l00392"></a><a class="code" href="logmath_8h.html#a5eb70928578b0115c9c7ac2765396a06">00392</a> <a class="code" href="logmath_8h.html#a5eb70928578b0115c9c7ac2765396a06" title="Add two values in log space (i.e.">logmath_add</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, <span class="keywordtype">int</span> logb_x, <span class="keywordtype">int</span> logb_y)
<a name="l00393"></a>00393 {
<a name="l00394"></a>00394 <a class="code" href="structlogadd__s.html">logadd_t</a> *t = <a class="code" href="logmath_8h.html#ae5c5ce106e9f8f1e763d419de53317a8" title="Obtain the log-add table from a logmath_t *.">LOGMATH_TABLE</a>(lmath);
<a name="l00395"></a>00395 <span class="keywordtype">int</span> d, r;
<a name="l00396"></a>00396
<a name="l00397"></a>00397 <span class="comment">/* handle 0 + x = x case. */</span>
<a name="l00398"></a>00398 <span class="keywordflow">if</span> (logb_x <= lmath->zero)
<a name="l00399"></a>00399 <span class="keywordflow">return</span> logb_y;
<a name="l00400"></a>00400 <span class="keywordflow">if</span> (logb_y <= lmath->zero)
<a name="l00401"></a>00401 <span class="keywordflow">return</span> logb_x;
<a name="l00402"></a>00402
<a name="l00403"></a>00403 <span class="keywordflow">if</span> (t-><a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a> == NULL)
<a name="l00404"></a>00404 <span class="keywordflow">return</span> <a class="code" href="logmath_8h.html#a61bf79c70a38f00ca060b69b0efd7489" title="Add two values in log space exactly and slowly (without using add table).">logmath_add_exact</a>(lmath, logb_x, logb_y);
<a name="l00405"></a>00405
<a name="l00406"></a>00406 <span class="comment">/* d must be positive, obviously. */</span>
<a name="l00407"></a>00407 <span class="keywordflow">if</span> (logb_x > logb_y) {
<a name="l00408"></a>00408 d = (logb_x - logb_y);
<a name="l00409"></a>00409 r = logb_x;
<a name="l00410"></a>00410 }
<a name="l00411"></a>00411 <span class="keywordflow">else</span> {
<a name="l00412"></a>00412 d = (logb_y - logb_x);
<a name="l00413"></a>00413 r = logb_y;
<a name="l00414"></a>00414 }
<a name="l00415"></a>00415
<a name="l00416"></a>00416 <span class="keywordflow">if</span> (d < 0) {
<a name="l00417"></a>00417 <span class="comment">/* Some kind of overflow has occurred, fail gracefully. */</span>
<a name="l00418"></a>00418 <span class="keywordflow">return</span> r;
<a name="l00419"></a>00419 }
<a name="l00420"></a>00420 <span class="keywordflow">if</span> ((<span class="keywordtype">size_t</span>)d >= t-><a class="code" href="structlogadd__s.html#a484c53a05b46d863d0456af679cee5d8" title="Number of elements in (table).">table_size</a>) {
<a name="l00421"></a>00421 <span class="comment">/* If this happens, it's not actually an error, because the</span>
<a name="l00422"></a>00422 <span class="comment"> * last entry in the logadd table is guaranteed to be zero.</span>
<a name="l00423"></a>00423 <span class="comment"> * Therefore we just return the larger of the two values. */</span>
<a name="l00424"></a>00424 <span class="keywordflow">return</span> r;
<a name="l00425"></a>00425 }
<a name="l00426"></a>00426
<a name="l00427"></a>00427 <span class="keywordflow">switch</span> (t-><a class="code" href="structlogadd__s.html#a8e35a353d751d957270baf5192007c3e" title="Width of elements of (table).">width</a>) {
<a name="l00428"></a>00428 <span class="keywordflow">case</span> 1:
<a name="l00429"></a>00429 <span class="keywordflow">return</span> r + (((uint8 *)t-><a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[d]);
<a name="l00430"></a>00430 <span class="keywordflow">case</span> 2:
<a name="l00431"></a>00431 <span class="keywordflow">return</span> r + (((uint16 *)t-><a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[d]);
<a name="l00432"></a>00432 <span class="keywordflow">case</span> 4:
<a name="l00433"></a>00433 <span class="keywordflow">return</span> r + (((uint32 *)t-><a class="code" href="structlogadd__s.html#a27793577d513d85cd73c2daffc140695" title="Table, in unsigned integers of (width) bytes.">table</a>)[d]);
<a name="l00434"></a>00434 }
<a name="l00435"></a>00435 <span class="keywordflow">return</span> r;
<a name="l00436"></a>00436 }
<a name="l00437"></a>00437
<a name="l00438"></a>00438 <span class="keywordtype">int</span>
<a name="l00439"></a><a class="code" href="logmath_8h.html#a61bf79c70a38f00ca060b69b0efd7489">00439</a> <a class="code" href="logmath_8h.html#a61bf79c70a38f00ca060b69b0efd7489" title="Add two values in log space exactly and slowly (without using add table).">logmath_add_exact</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, <span class="keywordtype">int</span> logb_p, <span class="keywordtype">int</span> logb_q)
<a name="l00440"></a>00440 {
<a name="l00441"></a>00441 <span class="keywordflow">return</span> <a class="code" href="logmath_8h.html#aebb4711268322fa7aec31e5798fe7e90" title="Convert linear floating point number to integer log in base B.">logmath_log</a>(lmath,
<a name="l00442"></a>00442 <a class="code" href="logmath_8h.html#ae8b0a168e29e448c0d6de66dc46e099e" title="Convert integer log in base B to linear floating point.">logmath_exp</a>(lmath, logb_p)
<a name="l00443"></a>00443 + <a class="code" href="logmath_8h.html#ae8b0a168e29e448c0d6de66dc46e099e" title="Convert integer log in base B to linear floating point.">logmath_exp</a>(lmath, logb_q));
<a name="l00444"></a>00444 }
<a name="l00445"></a>00445
<a name="l00446"></a>00446 <span class="keywordtype">int</span>
<a name="l00447"></a><a class="code" href="logmath_8h.html#aebb4711268322fa7aec31e5798fe7e90">00447</a> <a class="code" href="logmath_8h.html#aebb4711268322fa7aec31e5798fe7e90" title="Convert linear floating point number to integer log in base B.">logmath_log</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, float64 p)
<a name="l00448"></a>00448 {
<a name="l00449"></a>00449 <span class="keywordflow">if</span> (p <= 0) {
<a name="l00450"></a>00450 <span class="keywordflow">return</span> lmath->zero;
<a name="l00451"></a>00451 }
<a name="l00452"></a>00452 <span class="keywordflow">return</span> (<span class="keywordtype">int</span>)(log(p) * lmath->inv_log_of_base) >> lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>;
<a name="l00453"></a>00453 }
<a name="l00454"></a>00454
<a name="l00455"></a>00455 float64
<a name="l00456"></a><a class="code" href="logmath_8h.html#ae8b0a168e29e448c0d6de66dc46e099e">00456</a> <a class="code" href="logmath_8h.html#ae8b0a168e29e448c0d6de66dc46e099e" title="Convert integer log in base B to linear floating point.">logmath_exp</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, <span class="keywordtype">int</span> logb_p)
<a name="l00457"></a>00457 {
<a name="l00458"></a>00458 <span class="keywordflow">return</span> pow(lmath->base, (float64)(logb_p << lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>));
<a name="l00459"></a>00459 }
<a name="l00460"></a>00460
<a name="l00461"></a>00461 <span class="keywordtype">int</span>
<a name="l00462"></a><a class="code" href="logmath_8h.html#a52eff2c778ad758888b03ac5efcdccea">00462</a> <a class="code" href="logmath_8h.html#a52eff2c778ad758888b03ac5efcdccea" title="Convert natural log (in floating point) to integer log in base B.">logmath_ln_to_log</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, float64 log_p)
<a name="l00463"></a>00463 {
<a name="l00464"></a>00464 <span class="keywordflow">return</span> (<span class="keywordtype">int</span>)(log_p * lmath->inv_log_of_base) >> lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>;
<a name="l00465"></a>00465 }
<a name="l00466"></a>00466
<a name="l00467"></a>00467 float64
<a name="l00468"></a><a class="code" href="logmath_8h.html#a8035e176636eae8b4e02fe488f25457a">00468</a> <a class="code" href="logmath_8h.html#a8035e176636eae8b4e02fe488f25457a" title="Convert integer log in base B to natural log (in floating point).">logmath_log_to_ln</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, <span class="keywordtype">int</span> logb_p)
<a name="l00469"></a>00469 {
<a name="l00470"></a>00470 <span class="keywordflow">return</span> (float64)(logb_p << lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>) * lmath->log_of_base;
<a name="l00471"></a>00471 }
<a name="l00472"></a>00472
<a name="l00473"></a>00473 <span class="keywordtype">int</span>
<a name="l00474"></a><a class="code" href="logmath_8h.html#aacb4dddeed63a61fb927915f7e3a642e">00474</a> <a class="code" href="logmath_8h.html#aacb4dddeed63a61fb927915f7e3a642e" title="Convert base 10 log (in floating point) to integer log in base B.">logmath_log10_to_log</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, float64 log_p)
<a name="l00475"></a>00475 {
<a name="l00476"></a>00476 <span class="keywordflow">return</span> (<span class="keywordtype">int</span>)(log_p * lmath->inv_log10_of_base) >> lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>;
<a name="l00477"></a>00477 }
<a name="l00478"></a>00478
<a name="l00479"></a>00479 float64
<a name="l00480"></a><a class="code" href="logmath_8h.html#a7c17cb624003975e84fbd141ca6e2e06">00480</a> <a class="code" href="logmath_8h.html#a7c17cb624003975e84fbd141ca6e2e06" title="Convert integer log in base B to base 10 log (in floating point).">logmath_log_to_log10</a>(<a class="code" href="structlogmath__s.html">logmath_t</a> *lmath, <span class="keywordtype">int</span> logb_p)
<a name="l00481"></a>00481 {
<a name="l00482"></a>00482 <span class="keywordflow">return</span> (float64)(logb_p << lmath->t.<a class="code" href="structlogadd__s.html#a4000a49e71ed2c09da4f34cb5ccaed4b" title="Right shift applied to elements in (table).">shift</a>) * lmath->log10_of_base;
<a name="l00483"></a>00483 }
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