Python numpy.signbit()用法及代码示例

numpy.signbit(array, out = None, where = True, casting = ‘same_kind’, order = ‘K’, dtype = None)：该数学函数可帮助用户进行元素-明智地检查符号位是否已设置。

参数：
array : [array_like]Input array or object whose elements, we need to check.
out : [ndarray, optional]Output array with same dimensions as Input array, placed with result.
**kwargs: Allows you to pass keyword variable length of argument to a function. It is used when we want to handle named argument in a function.
where : [array_like, optional]True value means to calculate the universal functions(ufunc) at that position, False value means to leave the value in the output alone.

返回： True, if sign-bit is set; else False.

码：

# Python program illustrating  
# signbit() method  
  
import numpy as np  
  
arr = [1, -23, +34, 11] 
print ("arr:", arr) 
  
print ("\nCheck for signbit:", np.signbit(arr)) 
  
out_arr = np.arange(4) 
print ("\nout_arr:", out_arr) 
  
np.signbit(arr, out = out_arr) 
  
print ("\nplacing signbit check values to out_arr:", out_arr)

输出：

arr: [1, -23, 34, 11]

Check for signbit: [False  True False False]

out_arr: [0 1 2 3]

placing signbit check values to out_arr: [0 1 0 0]