MATLAB: Error using atan2 Inputs must be real.

atan2codeerrorMATLABMATLAB and Simulink Student Suitematlab function

this programme and function keep saying :
*Error using atan2 Inputs must be real. line 4 'function file'
*Error line 14 'main programme
i made 'px,py,pz' as coments cause i dont know its supose to help
ps :didn't with it either
Main programme :
clear
clc
clf
a2=6.5;a3=0;d3=1.9;d4=6;
% px=[-0.7;-2.52;-1.13;-4.60;1.00;1.68];
% py=[11.70;10.10;1.54;7.10;5.00;1.18];
% pz=[-0.90;-1.63;-6.93;-1.38;-3.00;-6.94];
t=0:23;
px=30*t'.*cos(t');
py=1200-(30*t'.^2)/(50*pi);
pz=30*t'.*sin(t');
[theta,t1,t2,t3,t4,t5,t6]=part2(a2,a3,d3,d4,px,py,pz);
pxx=cos(t1).*(sin(t2+t3)*d4+a3*cos(t2+t3)+a2*cos(t2))-d3*sin(t1);
pyy=sin(t1).*(sin(t2+t3).*cos(t5)+sin(t2+t3)*d4+a3*cos(t2+t3)+a2*cos(t2));
pzz=cos(t2+t3)*d4-a3*sin(t2+t3)-a2*sin(t2);
figure(1),plot(t,t6,'r')
hold on 
plot(t,t1,'k')
plot(t,t2,'b')
plot(t,t3,'m')
plot(t,t4,'g')
plot(t,t5,'c')
grid on
hod off
figure(2)
plot3(0.001*px,0.005*py,0.001*pz,'r',pxx,pyy,pzz,'b')
grid on
hold off
The function file :
function [theta,t1,t2,t3,t4,t5,t6]=part2(a2,a3,d3,d4,px,py,pz)
t1=atan2(px(1),py(1))-atan2(d3,sqrt(px(1)^2+py(1)^2-d3^2));
k=(px(1)^2+py(1)^2+pz(1)^2-a2^2-a3^2-d3^2-d4^2)/2*a2;
t3=atan2(a3,d4)-atan2(k,sqrt(a3^2+d4^2-k(1)^2));
t23=antan2((-a3-a2*cos(t3))*pz(1)-(cos(t1)*px(1)+sin(t1)*py(1))*(d4-a2*sin(t3)),(a2*sin(t3)-d4)*pz(1)+(a3+a2*cos(t3))*(cos(t)*px(1)+sin(t1)*px(1)+sin(t1)*py(1)));
t2=t23-t3;t4=0;t5=0;t6=0;
c1=cos(t1);s1=sin(t1);c2=cos(t2);s2=sin(t2);c3=cos(t3);s3=sin(t3);c23=cos(t23);s23=sin(t23);c4=cos(t4);c5=cos(t5);s5=sin(t5);c6=cos(t6);s6=sin(t6);
r13=-c1*(c23*c4*s5+s23*c5)-s1*s4*s5;
r23=-s1*c(23*c4*s5+s23*c5)+c1*s4*s5;
r33=s23*c4*s5-c23*c5;
r11=c1*(c23*(c4*c5*c6-s4*s6)-s23*s5*c6)+s1*(s4*c5*c6+c4*s6);
r21=s1*(c23*(c4*c5*c6-s4*s6)-s23*s5*c6)-c1*(s4*c5*c6+c4*s6);
r31=-s23*(c4*c5*c6-s4*s6)-c23*s5*c6;
for i=2:24
t1(i,1)=atan2(px(i,1),py(i,1))-atan2(d3,sqrt(px(i,1)^2+py(i,1)^2-d3^2));
k(i,1)=(px(i,1)^2+p(i,1)^2+pz(i,1)^2-a2^2-a3^2-d3^2-d4^2)/2*a2;
t3(i,1)=atan2(a3,d4)-atan2(k(i,1),sqrt(a3^2+d4^2-k(i,1)^2));
t23(i,1)=atan2((-a3-a2*cos(t3(i-1,1)))*pz(i,1)-cos(t1(i-1,1))*px(i,1)+sin(t1(i-1,1))*py(i,1)*(d4-a2*sin(t3(i-1,1))),(a2*sin(t3(i-1,1))-d4)*pz(i,1)+(a3+a2*cos(t3(i-1,1)))*(cos(t1(i-1,1))*px(i,1)+sin(t1(i-1,1))*px(i,1)+sin(t1(i-1,1))*py(i,1)));
t2(i,1)=t23(i,1-t3(i,1));
c1=cos(t1(i-1,1));s1=sin(t1(i-1,1));c2=cos(t2(i-1,1));s2=sin(t2(i-1,1));c3=cos(t3(i-1,1));
s3=sin(t3(i-1,1));c23=cos(t23(i-1,1));s23=sin(t23(i-1,1));c4=cos(t4(i-1,1));s4=sin(t4(i-1,1));
c5=cos(t5(i-1,1));s5=sin(t5(i-1,1));c6=cos(t6(i-1,1));s6=cos(t6(i-1,1));
r13(i-1,1)=-c1*(c23*c4*s5+s23*c5)-s1*s4*s5;
r23(i-1,1)=-s1*(c23*c4*s5+s23*c5)+c1*s4*s5;
r33(i-1,1)=s23*c4*s5-c23*c5;
t4(i,1)=atan2(-r13(i-1,1)*s1+r23(i-1,1)*c1,-r13(i-1,1)*c1*c23-r23(i-1,1)*s1*c23+r33(i-1,1)*s23);
s5=-r13(i-1,1)*(c1*c23*c4+s1*s4)+r23(i-1,1)*(s1*c23*c4-c1*s4)-r33(i-1,1)*s23*c4;
c5=r11(i-1,1)*(-c3*s23)+r23(i-1,1)*(-s1*s23)+r33(i-1,1)*(-c23);
t5(i,1)=atan2(s5,c5);
r11(i-1,1)=c1*(c23*(c4*c5*c6-s4*s6)-s23*s5*c6)+s1*(s4*c5*c6+c4*s6);
s6=-r11(i-1,1)*(c1*c23*s4-s1*c4)-r21(i-1,1)*(s1*c23*s4+c1*c4)+r31(i-1,1)*s23*s4;
c6=r11(i-1,1)*((c1*c23*c4+s1*s4)*c5-c1*s23*s5)+r21(i-1,1)*((s1*c23*c4-c1*s4)*c5-c1*s23*s5)-r31(i-1,1)*(s23*c4*c5+c23*s5);
t6(i,1)=atan2(s6,c6);
end
theta=[t1,t2,t3,t4,t5,t6]

Best Answer

If you want to compute the phase angle of a complex number, use the angle function.
Related Question