在循环中附加值

Append a value in for-loop

本文关键字:附加值 循环      更新时间:2023-10-16

我在qpolygonf值的附加/增量中有一个问题:我将一些点推入其中,然后将其连续得出,然后将点上的积分发送到其他类。

...
QPolygonF points;
for(int i= 0; i< 5; ++i)
{
  double value= finalMat.at<double>(i);
  points.push_back(QPointF((double)i, value));
  //points << QPointF((double)i, value);
}
qDebug()<<"points: " << points;
emit updatePointsSignal(points);

此代码块在达到条件号后删除了旧点,并通过新索引发送5个新点。输出为:

points: QPolygonF(0, pointValue) QPolygonF(1, pointValue) QPolygonF(2, pointValue) QPolygonF(3, pointValue) QPolygonF(4, pointValue) QPolygonF(0, newPointValue) QPolygonF(1, newPointValue)...

我如何递增我的点并发送它们而不删除旧点,以使输出看起来像?

 points: QPolygonF(0, pointValue) QPolygonF(1, pointValue) QPolygonF(2, pointValue) QPolygonF(3, pointValue) QPolygonF(4, pointValue) QPolygonF(5, newPointValue) QPolygonF(6, newPointValue) QPolygonF(7, newPointValue) QPolygonF(8, newPointValue)...

谢谢!

如果您想连续增量执行以下操作。

QPolygonF points;
static int indx = 0;
for(int i= 0; i< 5; ++i)
{
   double value= finalMat.at<double>(i);
   indx += i;
   points.push_back(QPointF((double)indx, value));
}
qDebug()<<"points: " << points;
emit updatePointsSignal(points);