Trouble with function calling

hi all

   could 1 me sketch , doesn't work , sketch has function takes 5 parameters , return float 1 , when try call function , on serial monitor , statement of "firststate" appeared before function call , neither returned value function , nor statement of "secondstate" appear , there syntax error in function body ? 

code: [select]






const float golx=12;
const float goly=14;
const float n=0.005;
const int dstar=1;
const float qstar=1.5;
const float zeta=0.5;


 
float qx,qy,d1,d2,d3,th,zzz;           
int obs1[2];      // array
int obs2[2];     
int obs3[2];
float gatt [2];
float grep [2];
float resultant [2];



 
  void setup() {
  // put setup code here, run once:
serial.begin(115200);
}


   
    void loop() {
  // put main code here, run repeatedly:
serial.println("firststate");
zzz=apftt(3,4,1,1.4,3);
serial.println(zzz);
serial.println("secondstate");

}




float apftt (float xc,float yc,float sf,float sl,float sr) {
  qx=xc;
  qy=yc;
    float dq ;
    dq = sqrt (pow((qx-golx),2) + pow((qy-goly),2));
   
    if (dq < dstar )
{
       
          gatt [1]= zeta * (qx - golx);
          gatt [2]= zeta * (qy - goly);   
}         
    else     
     
{
          gatt[1] =dstar * zeta *  (qx - golx  )/ dq;
          gatt[2] =dstar * zeta *  (qy - goly  )/ dq;
         
}
   

  d1 = sf;     
 

            if (d1<qstar && d1>0){
                obs1[1] = xc + d1;
                obs1[2] = yc + d1;
             

grep[1] = grep[1] +  (n * (   (1/qstar) - (1/d1)   ) * ((qx - obs1[1])/ pow(d1,2)));
grep[2] = grep[2] +  (n * (   (1/qstar) - (1/d1)   ) * ((qy - obs1[2])/ pow(d1,2))); }
         
 
  d2 = sl;     

            if (d2<qstar && d2>0){
                obs2[1] = xc + d2;
                obs2[2] = yc + d2;
             


grep[1] = grep[1] +  (n * (   (1/qstar) - (1/d2)   ) * ((qx - obs2[1])/ pow(d2,2)));
grep[2] = grep[2] +  (n * (   (1/qstar) - (1/d2)   ) * ((qy - obs2[2])/ pow(d2,2))); }


d3 = sr;     

            if (d3<qstar && d3>0){
                obs3[1] = xc + d3;
                obs3[2] = yc + d3;
             

grep[1] = grep[1] +  (n * (   (1/qstar) - (1/d3)   ) * ((qx - obs3[1])/ pow(d3,2)));
grep[2] = grep[2] +  (n * (   (1/qstar) - (1/d3)   ) * ((qy - obs3[2])/ pow(d3,2))); }



         
         
   // resultant = -1* (gatt + grep);
   
   resultant[1] = -1* (gatt[1] + grep[1]);
   resultant[2] = -1* (gatt[2] + grep[2]); 
   

 
   th= atan2(resultant[2] , resultant[1]);//%* 180/3.14 ;
return th;
}





hi maria88

code: [select]

int obs1[2];      // array
...
obs1[1] = xc + d1;
obs1[2] = yc + d1;

when declare arrays 2 elements, these elements numbered 0 , 1.  in code, however, trying access elements numbered 1 , 2. 

reading element 2 give incorrect data.  writing element 2 corrupt memory , cause strange behaviour.

try correcting , see if helps problem.

regards

ray

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