sym2cell not working even for the example given in document.

syms x y S = [x 2 3 4; y 6 7 8; 9 10 11 12]

S =

[ x, 2, 3, 4] [ y, 6, 7, 8] [ 9, 10, 11, 12]

c=sym2cell(S) Undefined function 'sym2cell' for input arguments of type 'sym'.

Answer 1

[Steven Lord]

According to the note at the bottom of the documentation page this function was introduced in release R2016a. I suspect you're using an earlier release of Symbolic Math Toolbox.

[Parikshit Pareek]

Yes,How can i get numerical value of symbolic equation? my code is

      syms Pgx Pdx Vx thi th_i th_j Gxy Bxy Qgx Qdy

N_bus=3;

Pgx=sym('Pgx',[1 N_bus]);
Pdx=sym('Pdx',[1 N_bus]);
V=sym('Vx%d%d',[1 N_bus]);
thi=sym('thi%d%d',[1 N_bus]);
thj=sym('thj%d%d',[1 N_bus]);
Gxy=sym('Gxy%d%d',[N_bus N_bus]);
Bxy=sym('Bxy%d%d',[N_bus N_bus]);

for k=1:N_bus
    for l=1:N_bus
    th_i(k,l)=thi(k);
    th_j(k,l)=thj(k);
    end 
end

th=th_i-th_j.';
%Calculate formula of the power drown from the 'x' bus
Gp=Gxy.*cos(th);
Bp=Bxy.*sin(th);
Yp=Gp+Bp;
If=V*Yp.';
PF_tot_x=V.*If;
WP=Pdx-Pgx+PF_tot_x;
WP2=WP.*WP;
for k=1:N_bus
    for l=1:N_bus
    ddWP_dVy(k,l)=diff(WP2(k),V(l),2);
    if (k~=l)
    ddWP_dth(k,l)=diff(WP2(k),thj(l),2);
    else
    ddWP_dth(k,l)=diff(WP2(k),thi(l),2);
    end
    end
end
  end

I have vectors for each variable.

[Walter Roberson]

subs() in all of the vectors at the same time. vpa() or double() the result.

[Parikshit Pareek]

subs() is working with 2 vectors at a time, else giving the error.

Gp=subs(Gp,[Gxy,thi,thj],[G,thi1,thj1]);
Error using sym/cat>checkDimensions (line 75)
CAT arguments dimensions are not consistent.

Error in sym/cat>catMany (line 38)
[resz, ranges] = checkDimensions(sz,dim);

Error in sym/cat (line 27)
    ySym = catMany(dim, strs);
Error in sym/horzcat (line 19)
    ySym = cat(2,args{:});
  end