some help needed with the TinyGPS library

hello -

i trying use of functions written in tinygps.h find heading, need on how call function. know if have define "currentcourse" string or float? right have float.

here's function trying call library:

const char *tinygps::cardinal (float course)
{
static const char* directions[] = {"n", "nne", "ne", "ene", "e", "ese", "se", "sse", "s", "ssw", "sw", "wsw", "w", "wnw", "nw", "nnw"};

int direction = (int)((course + 11.25f) / 22.5f);
return directions[direction % 16];
}

and code below, see function:void processgps()


also i'm getting error function saying "expected primary-expression before '==' token" --

i have long code attached , posted below. , guidance appreciated new arduino. if there's else find in code, can enhance or modify make better, please let me know. thanks!

code: [select]

/* dieudonné kaswa
 *  
 * goal of project similate self-driving car.
 *
 * */
 
 /*
  * hc-sr04 ping distance sensor:
  * vcc arduino 5v
  * gnd arduino gnd
  * trig arduino: right - pin13,  ctr - pin11, left - pin9
  * echo arduino: right - pin 12, ctr - pin10, left - pin8
 */

 /*
  * ublox - neo6m gps receiver
  * vcc arduino 5v
  * gnd arduino gnd
  * transmit signal on pin 4 arduino
  * receive  signal on pin 3 arduino
 */

// gps library , software serial
#include <softwareserial.h>
#include <tinygps.h>

// setting serial port , gps module
softwareserial gpsserial(4,3);            //rx,tx
tinygps gps;                              // creates gps object

// digital compass library & variables
#include <wire.h>
#include <adafruit_sensor.h>
#include <adafruit_lsm303_u.h>
#include <waypointclass.h>

// pin assignments
#define trigleft    9    // trigger left    sensor
#define trigctr     11   // trigger center  sensor
#define trigright   13   // trigger right   sensor
#define echoleft    8    // echo  left      sensor
#define echoctr     10   // echo  center    sensor
#define echoright   12   // echo  right     sensor
#define front1      a0   // motor 1, out 1
#define front2      a1   // motor 1, out 2
#define rear1       a2   // motor 2, out 3
#define rear2       a3   // motor 2, out 4
#define loaden      a4   // enable sig solenoid on a5
#define loaddrop    a5   // solenoid, out 4
#define greenled    7    // green led
#define redled      2    // red   led
#define ena         6    // enable sig mot1 pwm, black wire
#define enb         5    // enable sig mot2 pwm, brown wire
#define gpstx       4    // transmit signal pin, purple wire gps --> yellow wire arduino
#define gpsrx       3    // receive signal pin, blue wire
#define headingtol 10    // tolerance +/- (in degrees) within don't attempt turn intercept targetheading
/* waypoints */
#define waypoint_dist_tolerance  1   // tolerance in meters waypoint; once within tolerance, advance next waypoint
#define number_waypoints 3          // enter number of way points here (will run 0 (n-1))

// values initialization
/* motor speed variables */
int slowsp = 190;                     // rear motor slow spin speed
int maxrsp = 210;                     // rear motor max spin speed
int maxfsp = 250;                     // front motor max turn angle
/* ping sensor variables */
long duration;                        // duration used calculate distance ping sensor
int distance, distlft, distrgt;       // distance center ping sensor
/* compass variables */
int targetheading;                    // face reach destination
int currentheading;                   // facing
int headingerror;                     // signed (+/-) degrees difference between targetheading , currentheading
/* gps variables */
float currentcourse;
string latitude;  
string longitude;
float currentlat,
      currentlong,
      targetlat,
      targetlong;
int distancetotarget,                 // current distance target (current waypoint)
    originaldistancetotarget;         // distance original waypoing when started navigating it
int waypointnumber = -1;              // current waypoint number; run 0 (number_waypoints -1); start @ -1 , gets
                                      // initialized during setup()
waypointclass waypointlist[number_waypoints] = {
                                                waypointclass(30.508496, -97.832872),   // paul's douse
                                                waypointclass(30.508419, -97.832757),   // our house
                                                waypointclass(30.508296, -97.832618),   // ron's house
                                              };
adafruit_lsm303_mag_unified mag = adafruit_lsm303_mag_unified(12345);


// code begins
void setup()
{
  serial.begin(115200);     // connect serial
  gpsserial.begin(9600); // connect gps sensor

  //compass setup
  serial.println("magnetometer test"); serial.println("");
  
  // initialise magnetometer sensor
  if(!mag.begin())
  {
    // there problem detecting lsm303 ... check connections
    serial.println("ooops, no lsm303 detected ... check wiring!");
    while(1);
  }
  
  
 }

void loop()                       // main program loop
  {
    gpsloop();
    calcdesiredturn();  // calculate how optimatally turn, without regard obstacles          
    departled();
    movefwd();
    brake();
    dropload();
    delay (2000);
    destled();
    delay (2000);
    retunhome();
  }

void gpsloop()
{
  while(gpsserial.available())            // check gps data
  {
    if(gps.encode(gpsserial.read()))      // encode gps data
    {
      gps.f_get_position(&lat,&lon);      // latitude , longitude
     // gps.cardinal(course);              // tested
      // display position in serial window
      serial.print("latitude:");
      serial.print(lat,6);
      serial.print(";");
      serial.print("longitude:");
      serial.println(lon,6);  
      processgps();                       // process data gathered gps
     }
   }
    
    serial.println(lat);
    serial.println(lon);
        
    // navigate
    currentheading = readcompass();    // our current heading
}

// called after new gps data received; updates our position , course/distance waypoint
void processgps()
{
  currentlat = convertdegmintodecdeg(lat);
  currentlong = convertdegmintodecdeg(lon);
            
  if (gps.cardinal(currentcourse)) == 's')            // make them signed
    serial.println(gps.cardinal(currentcourse));
    currentlat = -currentlat;
  
  if (gps.cardinal(currentcourse)) == 'w')            // make them signed
    serial.println(gps.cardinal(currentcourse));
    currentlong = -currentlong;
            
  // update course , distance waypoint based on our new position
  //distancetowaypoint();
  gps.distance_between(currentlat, currentlong, targetlat, targetlong);
  //coursetowaypoint();
  gps.course_to(currentlat, currentlong, targetlat, targetlong);

}   // end of processgps(void)

int readcompass(void)
{
  /* new sensor event */
  sensors_event_t event;
  mag.getevent(&event);
  
  float pi = 3.14159;
  
  // calculate angle of vector y,x
  float heading = (atan2(event.magnetic.y,event.magnetic.x) * 180) / pi;
  
  // normalize 0-360
  if (heading < 0)
  {
    heading = 360 + heading;
  }
  //serial.print("compass heading: ");
  //serial.println(heading);
  //delay(500);
} // end of readcompass()

// way turn car , face destination?
void calcdesiredturn(void)
{
    // calculate need turn head destination
    headingerror = targetheading - currentheading; // signed (+/-) diff btw targetheading , currentheading
    
    // adjust compass wrap
    if (headingerror < -180)      
      headingerror += 360;
    if (headingerror > 180)
      headingerror -= 360;
  
    // calculate way turn intercept targetheading
    if (abs(headingerror) <= headingtol)      // if within tolerance of +/- 10
      serial.println("no turns");
    else if (headingerror < 0)
      turnleft();
    else if (headingerror > 0)
      turnright();
    else
      serial.println("no turns");
 
}  // end of calcdesiredturn()


// had chop of code make fit here within limits


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quote from: reaching48 on dec 10, 2017, 07:02 am

code: [select]

  if (gps.cardinal(currentcourse)) == 's')            // make them signed

count parentheses.

since you're "fairly new" recommend use braces ({}) enclose code controlled if statements, if there 1 line. makes easier understand intent of code , avoids tricky bugs.

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