Python – math.acos()函数

数学模块包含许多用于数学运算的函数。 math.acos()函数返回一个数字的反余弦值。在这个函数中传递的值应该在-1 到 1之间。

Syntax: math.acos(x)

Parameter:This method accepts only single parameters.

• x :This parameter is the value to be passed to acos()

Returns:This function returns the arc cosine value of a number.

下面的例子说明了上述函数的使用：

示例 1：

# Python code to implement
# the acos()function
       
# importing "math"
# for mathematical operations  
import math  
      
a = math.pi / 6
       
# returning the value of arc cosine of pi / 6  
print ("The value of arc cosine of pi / 6 is : ", end ="")  
print (math.acos(a))

输出：

The value of arc cosine of pi / 6 is : 1.0197267436954502

示例 2：

# Python code implementation of 
# the acos() function
import math 
import numpy as np 
import matplotlib.pyplot as plt  
    
in_array = np.linspace(-(1 / 3.5 * np.pi), 1 / 3.5 * np.pi, 20) 
    
out_array = [] 
    
for i in range(len(in_array)): 
    out_array.append(math.acos(in_array[i])) 
    i += 1
     
print("Input_Array : \n", in_array)  
print("\nOutput_Array : \n", out_array)  
  
  
plt.plot(in_array, out_array, "go-")  
plt.title("math.acos()")  
plt.xlabel("X")  
plt.ylabel("Y")  
plt.show() 

输出：

Input_Array :  
[-0.8975979  -0.80311391 -0.70862992 -0.61414593 -0.51966194 -0.42517795
 -0.33069396 -0.23620997 -0.14172598 -0.04724199  0.04724199  0.14172598
  0.23620997  0.33069396  0.42517795  0.51966194  0.61414593  0.70862992
  0.80311391  0.8975979 ]

Output_Array :  
[2.6850860217724004, 2.50329950258761, 2.358350863035667, 2.2320996324218134, 
2.1172515505585388, 2.009954812757658, 1.9078351422171613, 1.809259917693194,
1.7130011090538158, 1.6180559117526183, 1.5235367418371748, 1.4285915445359774,
1.3323327358965993, 1.233757511372632, 1.131637840832135, 1.0243411030312544,
0.9094930211679799, 0.783241790554126, 0.6382931510021833, 0.45650663181739287]