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11.51 Sample ‘error’ ¶

Function error draw error boxes around the points. You can draw default boxes or semi-transparent symbol (like marker, see Line styles). Also you can set individual color for each box. See also Sample ‘error2’.

MGL code:

call 'prepare1d'
new y 50 '0.7*sin(pi*x-pi) + 0.5*cos(3*pi*(x+1)/2) + 0.2*sin(pi*(x+1)/2)'
new x0 10 'x + 0.1*rnd-0.05':new ex 10 '0.1':new ey 10 '0.2'
new y0 10 '0.7*sin(pi*x-pi) + 0.5*cos(3*pi*(x+1)/2) + 0.2*sin(pi*(x+1)/2) + 0.2*rnd-0.1'
subplot 2 2 0 '':title 'Error plot (default)':box:plot y:error x0 y0 ex ey 'k'
subplot 2 2 1 '':title '"!" style; no e_x':box:plot y:error x0 y0 ey 'o!rgb'
subplot 2 2 2 '':title '"\@" style':alpha on:box:plot y:error x0 y0 ex ey '@'; alpha 0.5
subplot 2 2 3:title '3d variant':rotate 50 60:axis
for $1 0 9
	errbox 2*rnd-1 2*rnd-1 2*rnd-1 0.2 0.2 0.2 'bo'
next

C++ code:

void smgl_error2(mglGraph *gr)
{
	mglData x0(10), y0(10), ex(10), ey(10);
	for(int i=0;i<10;i++)
	{	x0.a[i] = mgl_rnd();	y0.a[i] = mgl_rnd();	ey.a[i] = ex.a[i] = 0.1;	}
	gr->SetRanges(0,1,0,1);	gr->Alpha(true);
	gr->SubPlot(4,3,0,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"#+@");
	gr->SubPlot(4,3,1,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"#x@");
	gr->SubPlot(4,3,2,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"#s@","alpha 0.5");
	gr->SubPlot(4,3,3,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"s@");
	gr->SubPlot(4,3,4,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"d@");
	gr->SubPlot(4,3,5,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"#d@","alpha 0.5");
	gr->SubPlot(4,3,6,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"+@");
	gr->SubPlot(4,3,7,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"x@");
	gr->SubPlot(4,3,8,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"o@");
	gr->SubPlot(4,3,9,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"#o@","alpha 0.5");
	gr->SubPlot(4,3,10,"");	gr->Box();	gr->Error(x0,y0,ex,ey,"#.@");
	gr->SubPlot(4,3,11,"");	gr->Box();	gr->Error(x0,y0,ex,ey);
}