How to replace equations in symbolic function
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Good Morning,
Please I have a function F = 3*a*b
Therefore how can i change (a*b) with a variable 'x' to obtain F = 3*x
Think you.
采纳的回答
Birdman
2020-3-27
By using subs function:
syms a b x
F=3*a*b;
Fnew=subs(F,{a,b},{x,1})
9 个评论
Birdman
2020-3-27
That 1 stands for replacing with b.
Your problem should be solved by the following code:
syms A B C D q1 q2 q3 t1 t2 t12 t23
F=A*q1^2+B*q2^2+C*q1*q2+D*q2*q3
%the following line does the trick
Fnew=subs(F,{q1^2,q2^2,q1*q2,q2*q3},{t1 t2 t12 t23})
Anis Frej
2020-3-27
I already did that but unfortunately does not work
Just t1 and t2 changes.
Birdman
2020-3-27
Which version of MATLAB are you using? I am using 2019b and it is working well for me.
Anis Frej
2020-3-27
Anis Frej
2020-3-27
Birdman
2020-3-27
Is there any chance you can use a newer release of MATLAB?
Anis Frej
2020-3-27
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