Computes the trigonometric sine function using a combination of table lookup and linear interpolation. There are separate functions for Q15, Q31, and floating-point data types. The input to the floating-point version is in radians while the fixed-point Q15 and Q31 have a scaled input with the range [0 +0.9999] mapping to [0 2*pi). The fixed-point range is chosen so that a value of 2*pi wraps around to 0.
The implementation is based on table lookup using 512 values together with linear interpolation. The steps used are:
- Calculation of the nearest integer table index
- Compute the fractional portion (fract) of the table index.
- The final result equals
(1.0f-fract)*a + fract*b;
where
b = Table[index];
c = Table[index+1];
- Parameters
-
[in] | x | Scaled input value in radians. |
- Returns
- sin(x).
- Parameters
-
[in] | x | Scaled input value in radians |
- Returns
- sin(x)
The Q15 input value is in the range [0 +0.9999] and is mapped to a radian value in the range [0 2*PI).
- Parameters
-
[in] | x | Scaled input value in radians. |
- Returns
- sin(x).
- Parameters
-
[in] | x | Scaled input value in radians |
- Returns
- sin(x)
The Q31 input value is in the range [0 +0.9999] and is mapped to a radian value in the range [0 2*PI).