npoles=3; poles[0]= [ 0,0]; poles[1]= [ 0,0]; poles[2]= [-1,0]; nzeros=0; k=1; //Gain multiplier function mcircle(m){ var y=[1,0]; for (var theta=-1;theta<5.28;theta+=.05){ y=[Math.cos(theta)/m-1, Math.sin(theta)/m]; Spot(y[0],y[1]); } Label('M='+m,y[0],y[1]+.01); } InitGraph(); ScaleWindow(-1.6,-1,1.6,1); DrawAxes(); LineStart(-1,-.05); //mark the -1 point LineTo(-1,0); Label('Whiteley with M-circles',.5,.8); for(m=1;m<7;m+=.5){ mcircle(m); } Colour(Black); var w=[0, 0]; var e=[0, 0]; LineStart(0.1,0); for(omega=.01;omega<10;omega*=1.01){ w[0]=0.1; w[1]=omega; e[0]=Math.cos(10*omega); e[1]=Math.sin(10*omega); cmul(w,e); LineTo(w[0],w[1]); //Inverse of gain }