科学计算器

支持三角函数/反三角函数，乘方，开方，指数，对数，阶乘，求和等基本运算
支持复数运算（直接输入),并支持角度表示和实部虚部表示之间的切换。
支持最多12个自定义函数 Support the basic operations of trigonometric / inverse trigonometric functions, involution, evolution, exponential, logarithmic, factorial, summation
Support complex operations (direct input), and the support angle and switching between the real and imaginary.
Support for up to 12 custom functions