Gps Declaration?

[mismael]

hi everybody;
i am using liblocation to get the direction of motion using the following code

if(device->fix->epd <= 10) //the accuracy must be less than 10 degree
    {
       data->m_track = device->fix->track;
     }

but i always get a wrong direction, is there any other thing that i should do.?

[divanov]

#include <QCoreApplication>
#include <QDebug>

extern "C" {
#include <location/location-gps-device.h>
#include <location/location-gpsd-control.h>
}

static void changed(LocationGPSDevice *device, gpointer userdata)
{
    Q_UNUSED(userdata);

    qDebug() << QString("%1\t%2\t%3\t%4\t%5\t%6\t%7\t%8\t%9\t%10")
                .arg(device->fix->time)
                .arg(device->fix->ept)
                .arg(device->fix->latitude)
                .arg(device->fix->longitude)
                .arg(device->fix->eph)
                .arg(device->fix->speed)
                .arg(device->fix->eps)
                .arg(device->fix->track)
                .arg(device->fix->epd)
                .arg(device->satellites_in_use);
}

static void connected(LocationGPSDevice *device, gpointer userdata)
{
    Q_UNUSED(device);
    Q_UNUSED(userdata);

    qDebug() << __PRETTY_FUNCTION__;
}

static void disconnected(LocationGPSDevice *device, gpointer userdata)
{
    Q_UNUSED(device);
    Q_UNUSED(userdata);

    qDebug() << __PRETTY_FUNCTION__;
}

int main(int argc, char *argv[])
{
    QCoreApplication app(argc, argv);
    LocationGPSDevice *device;
    LocationGPSDControl *control;

    g_type_init ();

    control = location_gpsd_control_get_default();
    if (control)
        location_gpsd_control_start(control);

    device = (LocationGPSDevice*)g_object_new(LOCATION_TYPE_GPS_DEVICE, NULL);
    if (device) {
        g_signal_connect(device, "changed", G_CALLBACK(changed), 0);
        g_signal_connect(device, "connected", G_CALLBACK(connected), 0);
        g_signal_connect(device, "disconnected", G_CALLBACK(disconnected), 0);
    }

    int ret = app.exec();

    if (device)
        g_object_unref(device);
    if (control)
        location_gpsd_control_stop(control);

    return ret;
}

What would be a log of this test app for you?

[mismael]

here are a part of the log file

"Direction 192.12 +- nan [0]" 
"Direction 192.12 +- nan [0]" 
"Direction 192.12 +- nan [0]" 
"Direction 192.12 +- nan [0]" 
"Direction 192.12 +- nan [7]" 
"Direction 307.19 +- 359.99 [8]" 
"Direction 216.5 +- 359.99 [5]" 
"Direction 63.33 +- 214.21 [5]" 
"Direction 118.35 +- 359.99 [5]" 
"Direction 105.53 +- 172.43 [5]" 
"Direction 223.79 +- 240.71 [6]" 
"Direction 68.98 +- 359.99 [4]" 
"Direction 221.34 +- 41.75 [5]" 
"Direction 221.34 +- 41.75 [5]" 
"Direction 221.34 +- 41.75 [4]" 
"Direction 235.97 +- 264.9 [4]" 
"Direction 235.97 +- 264.9 [7]"

[divanov]

Cool, accuracy is never less than 10. What is speed of your motion?

BTW, do you still insist that liblocation doesn't work with QCoreApplication?

[mismael]

i was walking on my foot.
now i am sure that liblocation work with QCOreApplication but i think that i should use g_type_init ();
which i did not use on my code.

[divanov]

I've updated the test application to produce more informative log. A direction accuracy is proportional to speed.

[mismael]

here is a part of the new log file

"Speed 0.648+-3.996 Direction 36.24+-359.99 [4]" 
"Speed 2.016+-5.364 Direction 37.21+-341.16 [4]" 
"Speed 3.42+-4.716 Direction 56.49+-121.19 [4]" 
"Speed 2.484+-7.164 Direction 313.1+-181.82 [4]" 
"Speed 1.116+-5.112 Direction 95.45+-359.99 [4]" 
"Speed 1.296+-6.408 Direction 52.22+-359.99 [4]" 
"Speed 2.7+-6.228 Direction 96.38+-202.68 [4]" 
"Speed 2.916+-3.096 Direction 68.96+-145.8 [4]" 
"Speed 3.132+-2.952 Direction 70.87+-107.7 [4]" 
"Speed 3.6+-4.176 Direction 104.52+-54.75 [4]" 
"Speed 0.936+-4.788 Direction 122.68+-359.99 [5]" 
"Speed 3.312+-5.58 Direction 133.09+-74.36 [4]" 
"Speed 3.384+-4.824 Direction 122.5+-60.33 [4]" 
"Speed 5.688+-5.292 Direction 113.42+-22.59 [4]" 
"Speed 3.816+-18.648 Direction 331.44+-72.88 [4]" 
"Speed 0.828+-9.468 Direction 243.07+-359.99 [4]" 
"Speed 0.828+-9.468 Direction 243.07+-359.99 [5]" 
"Speed 0.828+-9.468 Direction 243.07+-359.99 [4]" 
"Speed 7.704+-12.06 Direction 207.12+-71.76 [4]" 
"Speed 6.444+-18.288 Direction 265.56+-109.1 [4]" 
"Speed 8.928+-14.364 Direction 162.92+-110.81 [5]" 
"Speed 8.928+-14.364 Direction 162.92+-110.81 [6]" 
"Speed 1.656+-13.572 Direction 124.18+-359.99 [4]" 
"Speed 3.888+-8.928 Direction 176.46+-338.14 [4]" 
"Speed 2.844+-46.836 Direction 283.42+-321.52 [4]" 
"Speed 2.844+-46.836 Direction 283.42+-321.52 [5]" 
"Speed 2.844+-46.836 Direction 283.42+-321.52 [6]" 
"Speed 2.844+-46.836 Direction 283.42+-321.52 [5]" 
"Speed 12.528+-33.084 Direction 345.78+-16 [4]" 
"Speed 12.528+-33.084 Direction 345.78+-16 [4]" 
"Speed 12.528+-33.084 Direction 345.78+-16 [5]" 
"Speed 9.072+-16.74 Direction 1.65+-17.74 [5]"

[divanov]

I've collected large set of data and it makes no sense. File a bug to external Maemo bugzilla.
https://bugs.maemo.org/

[divanov]

I've collected large set of data and it makes no sense. File a bug to external Maemo bugzilla.
https://bugs.maemo.org/

Oh, wait, it actually does. You need to skip the data, where number of satellites were 0. Then it starts to make some sense.