python 的math函数库

秒速五厘米 2022-05-18 08:52 246阅读 0赞

<table> 
 <tbody> 
 <tr> 
 <td>函数</td> 
 <td>&nbsp;说明</td> 
 <td>&nbsp;实例</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.e</td> 
 <td>&nbsp;自然常数e</td> 
 <td>&nbsp;&gt;&gt;&gt; math.e 2.718281828459045</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.pi</td> 
 <td>&nbsp;圆周率pi</td> 
 <td>&nbsp;&gt;&gt;&gt; math.pi 3.141592653589793</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.degrees(x)</td> 
 <td>&nbsp;弧度转度</td> 
 <td>&nbsp;&gt;&gt;&gt; math.degrees(math.pi) 180.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.radians(x)</td> 
 <td>&nbsp;度转弧度</td> 
 <td>&nbsp;&gt;&gt;&gt; math.radians(45) 0.7853981633974483</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.exp(x)</td> 
 <td>&nbsp;返回e的x次方</td> 
 <td>&nbsp;&gt;&gt;&gt; math.exp(2) 7.38905609893065</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.expm1(x)</td> 
 <td>&nbsp;返回e的x次方减1</td> 
 <td>&nbsp;&gt;&gt;&gt; math.expm1(2) 6.38905609893065</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.log(x[, base])</td> 
 <td>&nbsp;返回x的以base为底的对数，base默认为e</td> 
 <td>&nbsp;&gt;&gt;&gt; math.log(math.e) 1.0 &gt;&gt;&gt; math.log(2, 10) 0.30102999566398114</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.log10(x)</td> 
 <td>&nbsp;返回x的以10为底的对数</td> 
 <td>&nbsp;&gt;&gt;&gt; math.log10(2) 0.30102999566398114</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.log1p(x)</td> 
 <td>&nbsp;返回1+x的自然对数（以e为底）</td> 
 <td>&nbsp;&gt;&gt;&gt; math.log1p(math.e-1) 1.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.pow(x, y)</td> 
 <td>&nbsp;返回x的y次方</td> 
 <td>&nbsp;&gt;&gt;&gt; math.pow(5,3) 125.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.sqrt(x)</td> 
 <td>&nbsp;返回x的平方根</td> 
 <td>&nbsp;&gt;&gt;&gt; math.sqrt(3) 1.7320508075688772</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.ceil(x)</td> 
 <td>&nbsp;返回不小于x的整数</td> 
 <td>&nbsp;&gt;&gt;&gt; math.ceil(5.2) 6.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.floor(x)</td> 
 <td>&nbsp;返回不大于x的整数</td> 
 <td>&nbsp;&gt;&gt;&gt; math.floor(5.8) 5.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.trunc(x)</td> 
 <td>&nbsp;返回x的整数部分</td> 
 <td>&nbsp;&gt;&gt;&gt; math.trunc(5.8) 5</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.modf(x)</td> 
 <td>&nbsp;返回x的小数和整数</td> 
 <td>&nbsp;&gt;&gt;&gt; math.modf(5.2) (0.20000000000000018, 5.0)</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.fabs(x)</td> 
 <td>&nbsp;返回x的绝对值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.fabs(-5) 5.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.fmod(x, y)</td> 
 <td>&nbsp;返回x%y（取余）</td> 
 <td>&nbsp;&gt;&gt;&gt; math.fmod(5,2) 1.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.fsum([x, y, ...])</td> 
 <td>&nbsp;返回无损精度的和</td> 
 <td>&nbsp;&gt;&gt;&gt; 0.1+0.2+0.3 0.6000000000000001 &gt;&gt;&gt; math.fsum([0.1, 0.2, 0.3]) 0.6</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.factorial(x)</td> 
 <td>&nbsp;返回x的阶乘</td> 
 <td>&nbsp;&gt;&gt;&gt; math.factorial(5) 120</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.isinf(x)</td> 
 <td>&nbsp;若x为无穷大，返回True；否则，返回False</td> 
 <td>&nbsp;&gt;&gt;&gt; math.isinf(1.0e+308) False &gt;&gt;&gt; math.isinf(1.0e+309) True</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.isnan(x)</td> 
 <td>&nbsp;若x不是数字，返回True；否则，返回False</td> 
 <td>&nbsp;&gt;&gt;&gt; math.isnan(1.2e3) False</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.hypot(x, y)</td> 
 <td>&nbsp;返回以x和y为直角边的斜边长</td> 
 <td>&nbsp;&gt;&gt;&gt; math.hypot(3,4) 5.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.copysign(x, y)</td> 
 <td>&nbsp;若y&lt;0，返回-1乘以x的绝对值； &nbsp;否则，返回x的绝对值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.copysign(5.2, -1) -5.2</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.frexp(x)</td> 
 <td>&nbsp;返回m和i，满足m乘以2的i次方</td> 
 <td>&nbsp;&gt;&gt;&gt; math.frexp(3) (0.75, 2)</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.ldexp(m, i)</td> 
 <td>&nbsp;返回m乘以2的i次方</td> 
 <td>&nbsp;&gt;&gt;&gt; math.ldexp(0.75, 2) 3.0</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.sin(x)</td> 
 <td>&nbsp;返回x（弧度）的三角正弦值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.sin(math.radians(30)) 0.49999999999999994</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.asin(x)</td> 
 <td>&nbsp;返回x的反三角正弦值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.asin(0.5) 0.5235987755982989</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.cos(x)</td> 
 <td>&nbsp;返回x（弧度）的三角余弦值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.cos(math.radians(45)) 0.7071067811865476</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.acos(x)</td> 
 <td>&nbsp;返回x的反三角余弦值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.acos(math.sqrt(2)/2) 0.7853981633974483</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.tan(x)</td> 
 <td>&nbsp;返回x（弧度）的三角正切值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.tan(math.radians(60)) 1.7320508075688767</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.atan(x)</td> 
 <td>&nbsp;返回x的反三角正切值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.atan(1.7320508075688767) 1.0471975511965976</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.atan2(x, y)</td> 
 <td>&nbsp;返回x/y的反三角正切值</td> 
 <td>&nbsp;&gt;&gt;&gt; math.atan2(2,1) 1.1071487177940904</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.sinh(x)</td> 
 <td>&nbsp;返回x的双曲正弦函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.asinh(x)</td> 
 <td>&nbsp;返回x的反双曲正弦函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.cosh(x)</td> 
 <td>&nbsp;返回x的双曲余弦函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.acosh(x)</td> 
 <td>&nbsp;返回x的反双曲余弦函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.tanh(x)</td> 
 <td>&nbsp;返回x的双曲正切函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.atanh(x)</td> 
 <td>&nbsp;返回x的反双曲正切函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.erf(x)</td> 
 <td>&nbsp;返回x的误差函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.erfc(x)</td> 
 <td>&nbsp;返回x的余误差函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.gamma(x)</td> 
 <td>&nbsp;返回x的伽玛函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 <tr> 
 <td>&nbsp;math.lgamma(x)</td> 
 <td>&nbsp;返回x的绝对值的自然对数的伽玛函数</td> 
 <td>&nbsp;</td> 
 </tr> 
 </tbody> 
</table>