python报错：ValueError: The truth value of an array with more than one element is ambiguous. Use a.any(

In determining whether a multi-element array is empty, he reported this wrong

if a:	# a是含有多个元素的numpy数组
	xxx

python error:

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

含有多个元素的数组在判断比较所有元素时，要用以上给定的any()或all()方法

Reference Solution: Learning Essay -ValueError: The truth value of an array with more than one element is ambiguous