jm1.c

通信中的数据解压缩。用一个字节存放整数部分

#include <stdio.h>
#include <math.h>

int n=50,m=1,k=4,count,cnt=1;
int z,z1,b,f,i;
double a,s;
double x[50]={29.3,29.3,29.3,29.3,29.4,29.3,29.5,29.5,29.3,29.5,29.5,29.6,29.8,29.6,29.3,29.5,29.6,29.5,29.3,29.6,29.5,29.7,29.7,29.6,29.7,29.6,29.5,29.5,29.5,29.5,29.6,29.5,29.6,29.6,29.6,29.6,29.6,29.7,29.5,29.6,29.5,29.6,29.7,29.8,29.6,29.7,29.7,29.6,29.7,29.7};
char y[100];
double J[100];
double *p1;
char *p2;
double *p3;


main()
{
p1=x;
p2=y;
p3=J;
a=x[0];
z=floor(a);
b=10*(a-z);
*p2=z;
p2++;
*p2=b;
while(m<n)
{
p1++;m++;
z1=floor(*p1);
if(z==z1)
{
	b=10*(*p1-z);
    if((k%2)!=0)
 {  
       
       *p2=(b<<4)|*p2;
	   k++;
 }
    else
 {
       p2++;
       *p2=b;
	   k++;
 }
}
else
{
    if((k%2)!=0)  
    {
		*p2=240|*p2;
		k++;
	}
	else
	{
	    p2++;
		*p2=255;
		k=k+2;
	}
		p2++;
		*p2=z1;
		z=z1;
		p2++;
		b=10*(*p1-z);
		*p2=b;
		k=k+3;
}
}
if((k%2)==0)
count=k/2;
else
count=(k+1)/2;
printf("%d",count);

p2=y;//解压 基本完全正确解压，最大误差正负0.1
s=*p2;
p2++;
f=*p2;
*p3=s+0.1*f;
while(cnt<count)
{
p2++;
f=15&(*p2);
if(f==15)
{
   p2++;
   s=*p2;
   cnt=cnt+2;
}
else
{
    p3++;
	*p3=s+0.1*f;
    f=(240&(*p2))>>4;
	if(f==15)
	{
	  p2++;
      s=*p2;
      cnt=cnt+2; 
	}
	else
	{
	    p3++;
		*p3=s+0.1*f;
		cnt++;
	}
	
}
}
for(i=0;i<n;i++)
printf("J[%d]=%f",i+1,J[i]);
}