固定小数点と2進数相互変換

IQ

IQmathConv.py

#coding:utf-8

import sys
import math

Q=32		#bit幅
IQ_bit=11	#小数点位置

def d_to_IQ(d):
	d_bin=format(d,'b').zfill(Q)

	ret=0.0
	for b in range(Q,-1,-1):
		bin_value_str=d_bin[b:b+1]
		if(len(bin_value_str)<1):
			continue
		bin_value=int(bin_value_str)
		if ((Q-b)==Q) and (bin_value==1):
			ret *= -1
		else:
			if(bin_value==1):
				ret += pow(2, ((Q-b)-(IQ_bit+1)))
	return ret

def IQ_to_d(iq):
	Flag=0
	IntBit=Q-IQ_bit-1
	DecBit=IQ_bit
	BitLength=IntBit+DecBit+1
	IntOut = ""
	DecOut = ""
	DecTemp = 0.0

	if iq<0:
		IntNum=-math.floor(-iq)	#整数部
		DecNum=abs(iq-IntNum)	#小数部
	else:
		IntNum=math.floor(iq)	#整数部
		DecNum=abs(iq-IntNum)	#小数部

	#小数部
	for i in range(1, IQ_bit+1):
		if DecNum==0:
			DecOut+="0"
		else:
			DecNum*=2
			if DecNum>=1:
				DecOut+="1"
				DecNum-=1
			else:
				DecOut+="0"
	#負のとき
	if iq < 0:
		for i in range(1, DecBit+1):
			DecTemp+= int(DecOut[-i]) * pow(2, (i-1))
		DecTemp = (pow(2, (DecBit+1))-1) - DecTemp	#2の補数
		DecTemp+=1
		if DecTemp >= pow(2, (DecBit+1)):
			Flag=1
		DecOut=""
		for i in range(DecBit-1, -1, -1):
			SignBit=(int(DecTemp) & pow(2, i))
			if SignBit!=0:
				DecOut+= "1"
			else:
				DecOut+="0"

	if iq>=0:
		IntNum=int(IntNum)
	else:
		IntNum=pow(2, (IntBit+1))-1+int(IntNum)
		if Flag==1:
			IntNum+=1
	for i in range(1, (IntBit+1)+1):
		SignBit=IntNum & pow(2, IntBit)	#最上位bitの1or0判定
		if SignBit!=0:
			IntOut+="1"
		else:
			IntOut+="0"
		IntNum*=2
		if IntNum >= (pow(2, (IntBit+1))-1):
			IntNum-=(pow(2, (IntBit+1))-1)
	return IntOut+DecOut

print d_to_IQ(364)

b=IQ_to_d(-1.50473253979636)
print b
print int(b,2)

参考