python math.asin

import math
math.asin(x)

x : -1 到 1 之间的数值。如果 x 是大于 1，会产生一个错误。

#!/usr/bin/python
import math

print "asin(0.64) : ", math.asin(0.64)
print "asin(0) : ", math.asin(0)
print "asin(-1) : ", math.asin(-1)
print "asin(1) : ", math.asin(1)

输出
asin(0.64) : 0.694498265627
asin(0) : 0.0
asin(-1) : -1.57079632679
asin(1) : 1.57079632679

https://www.runoob.com/python/func-number-asin.html