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39 lines
835 B
HTML
39 lines
835 B
HTML
<h1>数学函数 - fabs</h1>
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<p>原型：extern float fabs(float x);</p>
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<p>用法：#include <math.h></p>
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<p>功能：求浮点数x的绝对值</p>
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<p>说明：计算|x|, 当x不为负时返回x，否则返回-x</p>
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举例：<pre><code class="language-c">
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// fabs.c
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#include <syslib.h>
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#include <math.h>
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main()
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{
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float x;
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clrscr(); // clear screen
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textmode(0x00); // 6 lines per LCD screen
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x=-74.12;
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printf("|%f|=%f\n",x,fabs(x));
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x=0;
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printf("|%f|=%f\n",x,fabs(x));
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x=74.12;
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printf("|%f|=%f\n",x,fabs(x));
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getchar();
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return 0;
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}
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</code></pre>相关函数：<a href="abs.html">abs</a>
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