how to count the number of terms in syms

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EllaD
EllaD il 20 Ott 2020
Modificato: EllaD il 20 Ott 2020
Hello!
I have a syms variable let's say A which is an addition of many terms say: A=a+b-c*a+a*b-d+... I want to count the number of added terms in A, how can I do that? my matlab version is 2012 by the way.
Thank you!

Risposte (3)

Ameer Hamza
Ameer Hamza il 20 Ott 2020
Try this
syms a b c d
A=a+b-c*a+a*b-d+a*c;
num_terms = numel(regexp(char(A), '[+-]?'))+1;

Walter Roberson
Walter Roberson il 20 Ott 2020
feval(symengine, 'nops', A)
In newer releases you can numel(children(A)) but that is several years after your version
  1 Commento
EllaD
EllaD il 20 Ott 2020
Modificato: EllaD il 20 Ott 2020
Thanks but it seems that this doesnt work, I have 87 terms but this outputs 3.
EDIT: It is strange though, I checked this code for 5 terms and it does work.

Accedi per commentare.


KSSV
KSSV il 20 Ott 2020
You can get the number of sym variables present in the work spce using:
s = whos ;
iwant = nnz(strcmp({s(:).class},'sym'))

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