Power

Collaboration diagram for Power:

Functions
void	tpt_power_f32 (f32_t *aResult, const f32_t *aInData, uint32_t aCount)
	Sum of the squares of the elements of a floating-point vector. More...
void	tpt_power_f64 (f64_t *aResult, const f64_t *aInData, uint32_t aCount)
	Sum of the squares of the elements of a floating-point vector. More...
void	tpt_power_q15 (q33_30_t *aResult, const q15_t *aInData, uint32_t aCount)
	Sum of the squares of the elements of a Q15 vector. More...
void	tpt_power_q31 (q15_48_t *aResult, const q31_t *aInData, uint32_t aCount)
	Sum of the squares of the elements of a Q31 vector. More...
void	tpt_power_q7 (q17_14_t *aResult, const q7_t *aInData, uint32_t aCount)
	Sum of the squares of the elements of a Q7 vector. More...

Detailed Description

Calculates the sum of the squares of the elements in the input vector. The underlying algorithm is used:

   aResult = aInData[0] * aInData[0] + aInData[1] * aInData[1] + aInData[2] *
             aInData[2] + ... + aInData[aCount-1] * aInData[aCount-1];
 

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

Function Documentation

tpt_power_f32()

void tpt_power_f32	(	f32_t *	aResult,
		const f32_t *	aInData,
		uint32_t	aCount
	)

Sum of the squares of the elements of a floating-point vector.

Parameters

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

Returns

none

tpt_power_f64()

void tpt_power_f64	(	f64_t *	aResult,
		const f64_t *	aInData,
		uint32_t	aCount
	)

Sum of the squares of the elements of a floating-point vector.

Parameters

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

Returns

none

tpt_power_q15()

void tpt_power_q15	(	q33_30_t *	aResult,
		const q15_t *	aInData,
		uint32_t	aCount
	)

Sum of the squares of the elements of a Q15 vector.

Parameters

[out]	aResult	sum of the squares 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 1.15 format. Intermediate multiplication yields a 2.30 format, and this result is added without saturation to a 64-bit accumulator in 34.30 format. With 33 guard bits in the accumulator, there is no risk of overflow, and the full precision of the intermediate multiplication is preserved. Finally, the return result is in 34.30 format.

tpt_power_q31()

void tpt_power_q31	(	q15_48_t *	aResult,
		const q31_t *	aInData,
		uint32_t	aCount
	)

Sum of the squares of the elements of a Q31 vector.

Parameters

[out]	aResult	sum of the squares 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. Intermediate multiplication yields a 2.62 format, and this result is truncated to 2.48 format by discarding the lower 14 bits. The 2.48 result is then added without saturation to a 64-bit accumulator in 16.48 format. With 15 guard bits in the accumulator, there is no risk of overflow, and the full precision of the intermediate multiplication is preserved. Finally, the return result is in 16.48 format.

tpt_power_q7()

void tpt_power_q7	(	q17_14_t *	aResult,
		const q7_t *	aInData,
		uint32_t	aCount
	)

Sum of the squares of the elements of a Q7 vector.

Parameters

[out]	aResult	sum of the squares 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. Intermediate multiplication yields a 2.14 format, and this result is added without saturation to an accumulator in 18.14 format. With 17 guard bits in the accumulator, there is no risk of overflow, and the full precision of the intermediate multiplication is preserved. Finally, the return result is in 18.14 format.