Mean

Collaboration diagram for Mean:

Functions
void	tpt_mean_q15 (q15_t *aResult, const q15_t *aInData, uint32_t aCount)
	Mean value of a Q15 vector.
void	tpt_mean_q7 (q7_t *aResult, const q7_t *aInData, uint32_t aCount)
	Mean value of a Q7 vector.
void	tpt_mean_f32 (f32_t *aResult, const f32_t *aInData, uint32_t aCount)
	Mean value of a floating-point vector.
void	tpt_mean_f64 (f64_t *aResult, const f64_t *aInData, uint32_t aCount)
	Mean value of a floating-point vector.
void	tpt_mean_q31 (q31_t *aResult, const q31_t *aInData, uint32_t aCount)
	Mean value of a Q31 vector.

Detailed Description

Calculates the mean of the input vector. Mean is defined as the average of the elements in the vector. The underlying algorithm is used:

   aResult = (aInData[0] + aInData[1] + aInData[2] + ... + aInData[aCount-1])
             / aCount;
 

There are separate functions for floating-point, Q31, Q15, and Q7 data types.

Function Documentation

tpt_mean_f32()

void tpt_mean_f32	(	f32_t *	aResult,
		const f32_t *	aInData,
		uint32_t	aCount )

Mean value of a floating-point vector.

Parameters

[out]	aResult	mean value returned here.
[in]	aInData	points to the input vector.
[in]	aCount	number of samples in input vector.

Returns

none

tpt_mean_f64()

void tpt_mean_f64	(	f64_t *	aResult,
		const f64_t *	aInData,
		uint32_t	aCount )

Mean value of a floating-point vector.

Parameters

[out]	aResult	mean value returned here.
[in]	aInData	points to the input vector.
[in]	aCount	number of samples in input vector.

Returns

none

tpt_mean_q15()

void tpt_mean_q15	(	q15_t *	aResult,
		const q15_t *	aInData,
		uint32_t	aCount )

Mean value of a Q15 vector.

Parameters

[out]	aResult	mean value returned here.
[in]	aInData	points to the input vector.
[in]	aCount	number of samples in input vector.

Returns

none

Scaling and Overflow Behavior

The function is implemented using a 32-bit internal accumulator. The input is represented in 1.15 format and is accumulated in a 32-bit accumulator in 17.15 format. There is no risk of internal overflow with this approach, and the full precision of intermediate result is preserved. Finally, the accumulator is truncated to yield a result of 1.15 format.

tpt_mean_q31()

void tpt_mean_q31	(	q31_t *	aResult,
		const q31_t *	aInData,
		uint32_t	aCount )

Mean value of a Q31 vector.

Parameters

[out]	aResult	mean value returned here.
[in]	aInData	points to the input vector.
[in]	aCount	number of samples in input vector.

Returns

none

Scaling and Overflow Behavior

The function is implemented using a 64-bit internal accumulator. The input is represented in 1.31 format and is accumulated in a 64-bit accumulator in 33.31 format. There is no risk of internal overflow with this approach, and the full precision of intermediate result is preserved. Finally, the accumulator is truncated to yield a result of 1.31 format.

tpt_mean_q7()

void tpt_mean_q7	(	q7_t *	aResult,
		const q7_t *	aInData,
		uint32_t	aCount )

Mean value of a Q7 vector.

Parameters

[out]	aResult	mean value returned here.
[in]	aInData	points to the input vector.
[in]	aCount	number of samples in input vector.

Returns

none

Scaling and Overflow Behavior

The function is implemented using a 32-bit internal accumulator. The input is represented in 1.7 format and is accumulated in a 32-bit accumulator in 25.7 format. There is no risk of internal overflow with this approach, and the full precision of intermediate result is preserved. Finally, the accumulator is truncated to yield a result of 1.7 format.