Problems with nested indexing

34 views (last 30 days)
ROBSON SCHNEIDER
ROBSON SCHNEIDER on 14 Mar 2019
Commented: ROBSON SCHNEIDER on 27 Mar 2019
Hello,
I'm using a MATLAB algorithm to project and size the components of a vehicular suspension system.
In the following lines, an error is happening:
syms a2 b2
eq3=a2*Xmse+b2-Ymse;
eq4=a2*Xes+b2-Yes;
S2=solve(eq3,eq4);
a2=S2.a2(1);
b2=S2.b2(1);
OBS: the variables Xmse, Ymse, Xes and Yes are all real numbers.
This is the error that is happening every time I run the algorithm:
" Error using sym/subsref (line 747)
SYM objects do not allow nested indexing. Assign intermediate values to variables instead.
Error in projeto_de_suspensao (line 136)
a2=S2.a2(1); "
I don't know how to fix it. Can you help me?
Thanks for the support
  2 Comments
Walter Roberson
Walter Roberson on 23 Mar 2019
Which MATLAB release are you using? I do not get that error.
The message you are getting is what you would get if the result of the solve() were a single symbolic expression rather than a structure of results. You would get a single result if eq4 somehow ended up being a scalar symbolic variable name
ROBSON SCHNEIDER
ROBSON SCHNEIDER on 27 Mar 2019
MATLAB Release R2015a, Version 8.5.0.197613

Sign in to comment.

Answers (1)

madhan ravi
madhan ravi on 14 Mar 2019
Edited: madhan ravi on 23 Mar 2019
Remove (1) from the last two lines.
  1 Comment
madhan ravi
madhan ravi on 14 Mar 2019
Edited: madhan ravi on 14 Mar 2019
Alternative:
[a2,b2]=solve(eq3,eq4,[a2,b2])

Sign in to comment.

Categories

Find more on Symbolic Math Toolbox in Help Center and File Exchange

Community Treasure Hunt

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

Start Hunting!