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Re: Matrix formed in for loop
Posted:
Feb 27, 2013 11:50 AM


"Lakshmi " <guesswho1705@yahoo.com> wrote in message news:kgjj2k$6p0$1@newscl01ah.mathworks.com... > Hi > > I am trying to generate a matrix in a for loop with it's elements as > symbols rather than actual numbers. I want to later use this matrix in > another loop where the symbols values are assigned but the values change > with every loop. > Initially I had tried putting the loop developing the matrix within the > loop that gives the values, but it threw an error saying number of matrix > elements should be definite. > > The problem I am having currently is when I execute this piece of code > for cc1=1:4 > for cc2=1:4 > for cc3=1:4 > for cc4=1:4 > Tc(ac,1)=expand(T1(cc1))*(T2(cc2))*(T3(cc3))*(T4(cc4)); > ac=ac+1; > end > end > end > end > > where T1,2,3,4 are matrices with symbolic elements, > > I get this error > ??? The following error occurred converting from sym to double: > Error using ==> mupadmex > Error in MuPAD command: DOUBLE cannot convert the input expression into a > double array. > > If the input expression contains a symbolic variable, use the VPA function > instead.
Preallocate Tc to be a _symbolic_ matrix not a numeric matrix.
Tc = sym(zeros(4^4, 1));
 Steve Lord slord@mathworks.com To contact Technical Support use the Contact Us link on http://www.mathworks.com



