-how to run a function in separate thread

[wysota]

I am trying on both the version Qt 4 as well as on Qt 5

In Qt5 your project file needs a "QT += concurrent" line for QtConcurrent to work.

As for running a function in a thread, if it is a fire-and-forget situation, the two easiest approaches are to use QtConcurrent:run() or QRunnable in case you have problems in assembling a proper direct call to QtConcurrent::run().

[shivendra46d]

I tried running in QTConcurrent my function

void SRP_Ray_Plot(double No_Of_Rays, double Max_Range,double Source_Depth,double Initial_Angle, double Angle_Difference);

like this

QFuture<void> future = QtConcurrent::run(SRP_Ray_Plot, number_of_rays, max_range, source_depth,initial_angle,Angle_Difference);

but it is giving me error

mainwindow.cpp:1155: error: no matching function for call to `run(<unknown type>, double&, double&, double&, double&, double&)'

in the include i tried using

#include<QTConcurent>

but it shows error no such file or directory
and when i use

#include <qtconcurrentrun.h>

the error about no such file is removed.
Where i am wrong ?

[wysota]

#include <QtConcurrentRun>
 
void SRP_Ray_Plot(double No_Of_Rays, double Max_Range, double Source_Depth, double Initial_Angle, double Angle_Difference) {
  Q_UNUSED(No_Of_Rays); Q_UNUSED(Max_Range); Q_UNUSED(Source_Depth); Q_UNUSED(Initial_Angle); Q_UNUSED(Angle_Difference);
}
 
int main() {
  QFuture<void> future = QtConcurrent::run(SRP_Ray_Plot, 1, 1, 1, 1, 1);
  return 0;
}

#include <QtConcurrentRun>

void SRP_Ray_Plot(double No_Of_Rays, double Max_Range, double Source_Depth, double Initial_Angle, double Angle_Difference) {
  Q_UNUSED(No_Of_Rays); Q_UNUSED(Max_Range); Q_UNUSED(Source_Depth); Q_UNUSED(Initial_Angle); Q_UNUSED(Angle_Difference);
}

int main() {
  QFuture<void> future = QtConcurrent::run(SRP_Ray_Plot, 1, 1, 1, 1, 1);
  return 0;
}

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QT = core
TEMPLATE = app
TARGET = concurrent

QT = core
TEMPLATE = app
TARGET = concurrent

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