##### numpy 算术运算 ```python np.add(x1, x2, /[, out, where, casting, order, ...]) # 相加 [ufunc] np.reciprocal(x, /[, out, where, casting, ...]) # 倒数 [ufunc] np.positive(x, /[, out, where, casting, order, ...]) # 正值 [ufunc] np.negative(x, /[, out, where, casting, order, ...]) # 负值 [ufunc] np.multiply(x1, x2, /[, out, where, casting, ...]) # 相乘 [ufunc] np.np.divide(x1, x2, /[, out, where, casting, ...]) # 相除 [ufunc] np.power(x1, x2, /[, out, where, casting, ...]) # x1的x2次幂 [ufunc] np.subtract(x1, x2, /[, out, where, casting, ...]) # 相减 [ufunc] np.true_divide(x1, x2, /[, out, where, ...]) # 真除法运算 [ufunc] np.floor_divide(x1, x2, /[, out, where, ...]) # 返回小于或等于输入除法的最大整数 [ufunc] np.float_power(x1, x2, /[, out, where, ...]) # x1的x2次幂，返回浮点数结果 [ufunc] np.fmod(x1, x2, /[, out, where, casting, ...]) # 除法的余数 [ufunc] np.mod(x1, x2, /[, out, where, casting, order, ...]) # 除法的余数 [ufunc] np.modf(x[, out1, out2], / [[, out, where, ...]) # 小数部分和整数部分 [ufunc] np.remainder(x1, x2, /[, out, where, casting, ...]) # 除法的余数 [ufunc] np.divmod(x1, x2[, out1, out2], / [[, out, ...]) # 商和余数 [ufunc] ```