Using vpasolve to store an array of solutions

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I am trying to use an array as an input to plot multiple outputs that I also wish to recieve as arrays but I recieve this error
Error using mupadengine/feval (line 195)
More equations than variables is only supported for polynomial systems.
Here is the code I am trying to work with:
x=[0 360];
L2=.1;
L4=4.76;
L5=4.55;
theta2=99+x;
w2=10;
anga2=0;
syms theta4 theta5 la lc
eqn1=L2*cosd(theta2)-la*cosd(theta4)+1.69*cosd(15.5)==0;
eqn2=L2*sind(theta2)-la*sind(theta4)+1.69*sind(15.5)==0;
eqn3=L4*cosd(theta4)-L5*cosd(theta5)+lc==0;
eqn4=L4*sind(theta4)-L5*sind(theta5)-(2.86+1.69*sind(15.5))==0;
s=vpasolve([eqn1,eqn2,eqn3,eqn4],[theta4,theta5,la,lc]);
theta4=s.theta4;
theta5=s.theta5;
la=s.la;
lc=s.lc;

Answers (1)

Star Strider
Star Strider on 12 Jul 2020
Use solve instead of vpasolve, then use vpa on each of the results:
s=solve([eqn1,eqn2,eqn3,eqn4],[theta4,theta5,la,lc]);
stheta4 = vpa(s.theta4)
stheta5 = vpa(s.theta5)
sla = vpa(s.la)
slc = vpa(s.lc)
That will give you all of them.
.
  2 Comments
Ahmed Bedair
Ahmed Bedair on 12 Jul 2020
This is the output I get:
stheta4 =
Empty sym: 0-by-1
Star Strider
Star Strider on 12 Jul 2020
In R2020a Update 4, I get:
stheta4 =
18.842279938785301447678208983575
18.842279938785301447678208983575
-161.15772006121469855232179101643
-161.15772006121469855232179101643
stheta5 =
202.95208491158838934139316548765
-22.952084911588389341393165487651
- 90.0 + 20.657411926547563159279445881198i
270.0 - 20.657411926547563159279445881198i
sla =
1.7042190839952333693659000806486
1.7042190839952333693659000806486
-1.7042190839952333693659000806486
-1.7042190839952333693659000806486
slc =
-8.6946996593823179724949552072172
-0.31513491474309412760224942753366
4.5049172870627060500486023173754 + 1.6762282484967889104396885149306i
4.5049172870627060500486023173754 - 1.6762282484967889104396885149306i.
.

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