笔记：matlab中的sin(函数)
sin
Sine of an argument in radians
Syntax
Y = sin(X)
Description
The sin function operates element-wise on arrays. The function's domains and ranges include complex values. All angles are in radians.
Y = sin(X) returns the circular sine of the elements of X.
Examples
Graph the sine function over the domain
.
x = -pi:0.01:pi;
plot(x,sin(x)), grid on
The expression sin(pi) is not exactly zero, but rather a value the size of the floating-point accuracy eps, because pi is only a floating-point approximation to the exact value of
话说，这里的sin( -pi:0.01:pi)中的0.01是取样频率，-pi，pi是范围
也就是得到样本：｛-pi+0.01，-pi+0.02，-pi+0.03,......pi-0.01,pi｝
当然，这里的pi是近似值
