Plotting a multivariable function

1 view (last 30 days)
I wrote a code for plotting a mutivariable function but getting error like "Error using fplot (line 136)
Invalid parameter '0 ...'.
Error in SFDBMDNLK (line 83)
fplot(SF,x,SF1,x).
How can I resolve it?
code:
clear all
clc
format longEng
syms y1 y2 x
phi=(pi/180)*39;
delta=(pi/180)*26;
gma=18.4;
h=4;
h1=1.91;
h2=0.088;
L=h+h1+h2;
q=0;
beta=1;
alfa=1;
Ra1=-1;
Ra2=-(alfa*(y2))^0.5;
Rp1=3*(beta*(1-y1))^0.5;
Rp2=3*(alfa*(y2))^0.5;
delma1=0.5*(1-Ra1)*delta;
delma2=-0.5*(1-Ra2)*delta;
delmp1=0.5*(Rp1-1)*delta;
delmp2=0.5*(Rp2-1)*delta;
ka1=(2*cos(phi)^2)/(cos(phi)^2*(1+Ra1)+cos(delma1)*(1-Ra1)*(1+sqrt((sin(phi+delma1)*sin(phi))/cos(delma1)))^2);
ka2=(2*cos(phi)^2)/(cos(phi)^2*(1+Ra2)+cos(delma2)*(1-Ra2)*(1+sqrt((sin(phi+delma2)*sin(phi))/cos(delma2)))^2);
kp1=1+0.5*(Rp1-1)*((cos(phi)^2/(cos(delmp1)*(-sqrt((sin(phi+delmp1)*sin(phi))/cos(delmp1))+1)^2))-1);
kp2=1+0.5*(Rp2-1)*((cos(phi)^2/(cos(delmp2)*(-sqrt((sin(phi+delmp2)*sin(phi))/cos(delmp2))+1)^2))-1);
fup1=matlabFunction(kp1*y1*cos(delmp1));
Final_result_p1=gma*(x-h)^2*integral(fup1,0,1);
M21=matlabFunction(kp1*cos(delmp1)*y1);
Final_result_m21=gma*h1*(x-h)^2*integral(M21,0,1);
M22=matlabFunction(kp1*cos(delmp1)*y1^2);
Final_result_m22=gma*(x-h)^3*integral(M22,0,1);
Final_result_m2=Final_result_m21+Final_result_m22;
Hfup1=matlabFunction(kp1*y1*cos(delmp1));
HFinal_result_p1=gma*h1^2*integral(Hfup1,0,1);
T31=matlabFunction(kp2*cos(delmp2));
HFinal_result_T31=gma*(h+h1)*(x-h-h1)*integral(T31,0,1);
T32=matlabFunction(ka2*cos(delma2));
HFinal_result_T32=gma*h1*(x-h-h1)*integral(T32,0,1);
T33=matlabFunction(kp2*cos(delmp2)*y2-ka2*cos(delma2)*y2);
HFinal_result_T33=gma*(x-h-h1)^2*integral(T33,0,1);
T3=HFinal_result_T31+HFinal_result_T32+HFinal_result_T33;
M21=matlabFunction(kp1*cos(delmp1)*y1);
Result_M21=gma*h1*(x-h)^2*integral(M21,0,1);
M22=matlabFunction(kp1*cos(delmp1)*y1^2);
Result_M22=gma*(x-h)^3*integral(M22,0,1);
M23=matlabFunction(kp1*y1*cos(delmp1));
Result_M23=gma*(x-h-h1)*(x-h)^2*integral(M23,0,1);
M31=matlabFunction(kp2*cos(delmp2)*y2);
Result_M31=gma*(h+h1)*0.5*(x-h-h1)^2*integral(M31,0,1);
M32=matlabFunction(ka2*cos(delma2)*y2);
Result_M32=gma*h1*0.5*(x-h-h1)^2*integral(M32,0,1);
M3=Result_M31-Result_M32;
M4=matlabFunction((kp2*cos(delmp2)-ka2*cos(delma2))*y2*(1-y2));
Result_M4=gma*(x-h-h1)^3*integral(M4,0,1);
MT1=-0.5*ka1*gma*x^2*cos(delma1);
MM1=-(1/6)*ka1*gma*x^3*cos(delma1);
MT2=-0.5*ka1*gma*x^2*cos(delma1);
MM2=-(1/6)*ka1*gma*x^3*cos(delma1);
i=0;
for x=0:0.02:L
i=i+1;
if(x<h)
SF(i)=MT1;
SF1(i)=0;
BM(i)=MM1;
BM1(i)=0;
elseif(x>=h && x<(h+h1))
SF(i)=MT2+Final_result_p1;
SF1(i)=0;
BM(i)=MM2+Final_result_m2;
BM1(i)=0;
else
SF(i)=-0.5*ka1*gma*(h+h1)^2*cos(delma1) + HFinal_result_p1 - T3;
SF1(i)=0;
BM(i)=-0.5*ka1*gma*(h+h1)^2*(((h+h1)/3)+(x-h-h1))*cos(delma1)+ M3 - Result_M4; %0.5*kp1*gma*h1^2*((h1/3)+(x-h-h1))*cos(delmp1)-0.5*gma*(x-h-h1)^2*(kp2*(h+h1)*cos(delmp2)-ka2*h1*cos(delma2))-(1/6)*(kp2*cos(delmp2)-ka2*cos(delma2))*(x-h-h1)^3;
BM1(i)=0;
end
end
x=0:0.02:L;
subplot(2,1,1);
fplot(SF,x,SF1,x)
xlabel('Length of the beam in m')
ylabel('Shear Force in KN')
title('Shear force diagram')
col_header={'x',SF};
xlswrite('data.xlsx',[x(:),SF(:)],'Sheet1','A2');
xlswrite('data.xlsx',col_header,'Sheet1','A1');
subplot(2,1,2)
fplot(BM,x,BM1,x)
xlabel('Length of the beam in m')
ylabel('Bending Moment in KN-m')
title('Bending Moment diagram')
col_header={'x',BM};
xlswrite('data.xlsx',[x(:),BM(:)],'Sheet1','A2');
xlswrite('data.xlsx',col_header,'Sheet1','A1');
  1 Comment
KSSV
KSSV on 20 Feb 2019
Read the documentation of fplot. YOu are using wrong inputs.

Sign in to comment.

Accepted Answer

KSSV
KSSV on 20 Feb 2019
  1 Comment
Akshay Pratap Singh
Akshay Pratap Singh on 20 Feb 2019
Thanks KSSV, it worked, now reforming the code.
Thanks

Sign in to comment.

More Answers (0)

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!