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11.76 Sample ‘loglog’ ¶

Example of log- and log-log- axis labels.

MGL code:

subplot 2 2 0 '<_':title 'Semi-log axis':ranges 0.01 100 -1 1:axis 'lg(x)' '' ''
axis:grid 'xy' 'g':fplot 'sin(1/x)':xlabel 'x' 0:ylabel 'y = sin 1/x' 0
subplot 2 2 1 '<_':title 'Log-log axis':ranges 0.01 100 0.1 100:axis 'lg(x)' 'lg(y)' ''
axis:grid '!' 'h=':grid:fplot 'sqrt(1+x^2)'
xlabel 'x' 0:ylabel 'y = \sqrt{1+x^2}' 0
subplot 2 2 2 '<_':title 'Minus-log axis':ranges -100 -0.01 -100 -0.1:axis '-lg(-x)' '-lg(-y)' ''
axis:fplot '-sqrt(1+x^2)':xlabel 'x' 0:ylabel 'y = -\sqrt{1+x^2}' 0
subplot 2 2 3 '<_':title 'Log-ticks':ranges 0.01 100 0 100:axis 'sqrt(x)' '' ''
axis:fplot 'x':xlabel 'x' 1:ylabel 'y = x' 0

C++ code:

void smgl_loglog(mglGraph *gr)	// log-log axis
{
	gr->SubPlot(2,2,0,"<_");	gr->Title("Semi-log axis");	gr->SetRanges(0.01,100,-1,1);	gr->SetFunc("lg(x)","");
	gr->Axis();	gr->Grid("xy","g");	gr->FPlot("sin(1/x)");	gr->Label('x',"x",0); gr->Label('y', "y = sin 1/x",0);
	gr->SubPlot(2,2,1,"<_");	gr->Title("Log-log axis");	gr->SetRanges(0.01,100,0.1,100);	gr->SetFunc("lg(x)","lg(y)");
	gr->Axis();	gr->Grid("!","h=");	gr->Grid();	gr->FPlot("sqrt(1+x^2)");	gr->Label('x',"x",0); gr->Label('y', "y = \\sqrt{1+x^2}",0);
	gr->SubPlot(2,2,2,"<_");	gr->Title("Minus-log axis");	gr->SetRanges(-100,-0.01,-100,-0.1);	gr->SetFunc("-lg(-x)","-lg(-y)");
	gr->Axis();	gr->FPlot("-sqrt(1+x^2)");	gr->Label('x',"x",0); gr->Label('y', "y = -\\sqrt{1+x^2}",0);
	gr->SubPlot(2,2,3,"<_");	gr->Title("Log-ticks");	gr->SetRanges(0.1,100,0,100);	gr->SetFunc("sqrt(x)","");
	gr->Axis();	gr->FPlot("x");	gr->Label('x',"x",1); gr->Label('y', "y = x",0);
}