我编了一个程序，是用来做课程设计的！！！
作用很简单，就是给出已知数据，按照下面的公式计算出结果就行了！！
#include<math.h>
#include<stdio.h>
#define pi 3.1415926
void main()
{
 int A1,w1,L1,L3,L4,L6,l6;
 double A3,A4,S3,s3,w3,w4,a3,SE,VE,aE;
 FILE *in;
 if((in=fopen("D:\\results.txt","w"))==NULL)
 {printf("cannot open in\n");
  exit(0);
 }

   A1=0;
   w1=5;
   A3=0;
   L1=110;
   L3=650;
   L4=220;
   L6=350;
   l6=645;
 for(A1=0;A1<=360;A1=A1+2)
 {
     A3=atan(((L6+L1*sin(A1*pi/180))/(L1*cos(A1*pi/180)));
     S3=L1*cos(A1*pi/180)/cos(A3);
     s3=-w1*L1*sin(A1*pi/180-A3);
     w3=w1*L1*cos(A1*pi/180-A3)/S3;
     a3=(pow(w1,2)*L1*sin(A3-A1*pi/180)-2*w3*s3)/S3;
     A4=asin((l6/L4-L3*sin(A3)/L4));
     SE=L3*cos(A3)+L4*cos(A4);
     VE=(-w3)*L3*sin(A3-A4)/cos(A4);
     w4=(-w3)*L3*cos(A3)/(L4*cos(A4));
     aE=-(a3*L3*sin(A3-A4)+pow(a3,2)*L3*cos(A3-A4)-pow(a4,2)*L4)/cos(A4);
      printf("\nA3=%5.3f,S3=%5.3f,s3=%5.3f,w3=%5.3f,a3=%5.3f,A4=%5.3f,SE=%5.3f,VE=%5.3f,w4=%5.3f,aE=%5.3f\n",A3,S3,s3,w3,a3,A4,SE,VE,w4,aE);
      fprintf(in,"\nA3=%5.3f,S3=%5.3f,s3=%5.3f,w3=%5.3f,a3=%5.3f,A4=%5.3f,SE=%5.3f,VE=%5.3f,w4=%5.3f,aE=%5.3f\n",A3,S3,s3,w3,a3,A4,SE,VE,w4,aE);
    }
  fclose(in);
}

主要就是A3啊，怎么都是错！！！！！！！！！！！