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📜  Lua-数学库

📅  最后修改于: 2020-10-16 05:21:21             🧑  作者: Mango

在科学和工程计算中，我们经常需要数学运算，我们可以使用标准的Lua库数学来进行运算。下表显示了数学库中可用的功能列表。

Sr.No. Library / Method & Purpose
1

math.abs (x)

Returns the absolute value of x.
2

math.acos (x)

Returns the arc cosine of x (in radians).
3

math.asin (x)

Returns the arc sine of x (in radians).
4

math.atan (x)

Returns the arc tangent of x (in radians).
5

math.atan2 (y, x)

Returns the arc tangent of y/x (in radians), but uses the signs of both parameters to find the quadrant of the result. (It also handles correctly the case of x being zero.)
6

math.ceil (x)

Returns the smallest integer larger than or equal to x.
7

math.cos (x)

Returns the cosine of x (assumed to be in radians).
8

math.cosh (x)

Returns the hyperbolic cosine of x.
9

math.deg (x)

Returns the angle x (given in radians) in degrees.
10

math.exp (x)

Returns the value e power x.
11

math.floor (x)

Returns the largest integer smaller than or equal to x.
12

math.fmod (x, y)

Returns the remainder of the division of x by y that rounds the quotient towards zero.
13

math.frexp (x)

Returns m and e such that x = m2e, e is an integer and the absolute value of m is in the range [0.5, 1) (or zero when x is zero).
14

math.huge

The value HUGE_VAL, a value larger than or equal to any other numerical valu.
15

math.ldexp (m, e)

Returns m2e (e should be an integer).
16

math.log (x)

Returns the natural logarithm of x.
17

math.log10 (x)

Returns the base-10 logarithm of x.
18

math.max (x, …)

Returns the maximum value among its arguments.
19

math.min (x, …)

Returns the minimum value among its arguments.
20

math.modf (x)

Returns two numbers, the integral part of x and the fractional part of x.
21

math.pi

The value of pi.
22

math.pow (x, y)

Returns xy. (You can also use the expression x^y to compute this value.)
23

math.rad (x)

Returns the angle x (given in degrees) in radians.
24

math.random ([m [, n]])

This function is an interface to the simple pseudo-random generator function rand provided by ANSI C.When called without arguments, returns a uniform pseudo-random real number in the range [0,1). When called with an integer number m, math.random returns a uniform pseudo-random integer in the range [1, m]. When called with two integer numbers m and n, math.random returns a uniform pseudo-random integer in the range [m, n].
25

math.randomseed (x)

Sets x as the “seed” for the pseudo-random generator: equal seeds produce equal sequences of numbers.
26

math.sin (x)

Returns the sine of x (assumed to be in radians).
27

math.sinh (x)

Returns the hyperbolic sine of x.
28

math.sqrt (x)

Returns the square root of x. (You can also use the expression x^0.5 to compute this value.)
29

math.tan (x)

Returns the tangent of x (assumed to be in radians).
30

math.tanh (x)

Returns the hyperbolic tangent of x.

三角函数

使用函数一个简单的例子如下所示。

现场演示
radianVal = math.rad(math.pi / 2)

io.write(radianVal,"\n")

-- Sin value of 90(math.pi / 2) degrees
io.write(string.format("%.1f ", math.sin(radianVal)),"\n")

-- Cos value of 90(math.pi / 2) degrees
io.write(string.format("%.1f ", math.cos(radianVal)),"\n")

-- Tan value of 90(math.pi / 2) degrees
io.write(string.format("%.1f ", math.tan(radianVal)),"\n")

-- Cosh value of 90(math.pi / 2) degrees
io.write(string.format("%.1f ", math.cosh(radianVal)),"\n")

-- Pi Value in degrees
io.write(math.deg(math.pi),"\n")

当我们运行上面的程序时，我们将得到以下输出。

0.027415567780804
0.0 
1.0 
0.0 
1.0 
180

其他常用数学函数

下面显示了一个使用常见数学函数的简单示例。

现场演示
-- Floor
io.write("Floor of 10.5055 is ", math.floor(10.5055),"\n")

-- Ceil
io.write("Ceil of 10.5055 is ", math.ceil(10.5055),"\n")

-- Square root
io.write("Square root of 16 is ",math.sqrt(16),"\n")

-- Power
io.write("10 power 2 is ",math.pow(10,2),"\n")
io.write("100 power 0.5 is ",math.pow(100,0.5),"\n")

-- Absolute
io.write("Absolute value of -10 is ",math.abs(-10),"\n")

--Random
math.randomseed(os.time())
io.write("Random number between 1 and 100 is ",math.random(),"\n")

--Random between 1 to 100
io.write("Random number between 1 and 100 is ",math.random(1,100),"\n")

--Max
io.write("Maximum in the input array is ",math.max(1,100,101,99,999),"\n")

--Min
io.write("Minimum in the input array is ",math.min(1,100,101,99,999),"\n")

当我们运行上面的程序时，我们将得到以下输出。

Floor of 10.5055 is 10
Ceil of 10.5055 is 11
Square root of 16 is 4
10 power 2 is 100
100 power 0.5 is 10
Absolute value of -10 is 10
Random number between 1 and 100 is 0.22876674703207
Random number between 1 and 100 is 7
Maximum in the input array is 999
Minimum in the input array is 1

上面的例子只是一些常见的例子，我们可以根据需要使用数学库，因此请尝试使用所有函数以更加熟悉。