arm_nn_tables.h File Reference

Variables
const q15_t	sigmoidTable_q15 [256]
	tables for various activation functions More...
const q7_t	sigmoidTable_q7 [256]
	tables for various activation functions More...
const q7_t	tanhTable_q7 [256]
const q15_t	tanhTable_q15 [256]
const q15_t	sigmoidHTable_q15 [192]
	2-way tables for various activation functions More...
const q15_t	sigmoidLTable_q15 [128]

Variable Documentation

const q15_t sigmoidHTable_q15

2-way table, H table for value larger than 1/4 L table for value smaller than 1/4, H table for remaining We have this only for the q15_t version. It does not make sense to have it for q7_t type

const q15_t sigmoidLTable_q15

const q15_t sigmoidTable_q15[256]

Referenced by arm_nn_activations_direct_q15().

const q7_t sigmoidTable_q7[256]

This file include the declaration of common tables. Most of them are used for activation functions

Assumption: Unified table: input is 3.x format, i.e, range of [-8, 8) sigmoid(8) = 0.9996646498695336 tanh(8) = 0.9999997749296758 The accuracy here should be good enough

2-stage HL table:

The entire input range is divided into two parts:

Low range table: 0x000x xxxx or 0x111x xxxx table entry will be the binary number excluding the first two digits, i.e., 0x0x xxxx or 0x1x xxxx

High range table 0x0010 0000 – 0x0111 1111 0x1000 0000 – 0x1101 1111

For positive numbers, table entry will be 0x0010 0000 – 0x0111 1111 minus 0x0010 0000 i.e., 0x0000 0000 - 0x0101 11111

same thing for the negative numbers, table entry will be 0x1000 0000 – 0x1101 1111 minux 0x0010 0000 i.e., 0x0110 0000 - 0x1011 1111

Referenced by arm_nn_activations_direct_q7().

const q15_t tanhTable_q15[256]

Referenced by arm_nn_activations_direct_q15().

const q7_t tanhTable_q7[256]

Referenced by arm_nn_activations_direct_q7().