2-28重要笔记

	QVector<double>x(100000), y1(100000), y2(100000);
	for (int i=0;i< 100000;++i)
	{
   
		x[i] = double(i);
		y1[i] = log10(double(i));
		y2[i] = std::sin(double(i)/1000);
	}
	qcpw->addGraph(qcpw->xAxis, qcpw->yAxis);
	qcpw->addGraph(qcpw->xAxis, qcpw->yAxis2);
	qcpw->graph(0)->setData(x, y1);
	qcpw->graph(1)->setData(x, y2);
	qcpw->graph(0)->setAdaptiveSampling(true); //自适应样本，当样本很多时，可以减少卡顿
	qcpw->graph(0)->rescaleAxes(); //自适应坐标系
	qcpw->graph(1)->setAdaptiveSampling(true); //自适应样本，当样本很多时，可以减少卡顿
	qcpw->graph(1)->rescaleAxes(); //自适应坐标系
	qcpw->yAxis2->setVisible(true);
	//setAdaptiveSampling(true)很重要，能保证系统不卡
	qcpw->