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# Symbolic objects

## Symbolic objects

(OP)
Hi all,
How can I create a matrix of symbolic objects like
A=[a1,a2,a3,a4.........a60] using possibly an index

such as i=1:60 if possible .

Again is it possible to mix symbolic objects and numeric decimals in one matrix, such as
A=[a1,a2,a3,4,5,6,a4....]

cheers
musilj

### RE: Symbolic objects

A=[sym('a1'),sym('a2'),sym('a3'),4,5,6,sym('a4')....]

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### RE: Symbolic objects

#### Quote:

How can I create a matrix of symbolic objects like
A=[a1,a2,a3,a4.........a60] using possibly an index

#### CODE

for i=1:60
A(i)=sym(strcat('a',num2str(i)))
end

#### Quote:

Again is it possible to mix symbolic objects and numeric decimals in one matrix, such as
A=[a1,a2,a3,4,5,6,a4....]

#### CODE

A=[sym('a1'),sym('a2'),sym('a3'),4,5,6,sym('a4')....]

=====================================
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### RE: Symbolic objects

(OP)
hi electricpete

A quick paste into matlab of your code with the index resulted in the following error.

??? The following error occurred converting from sym to double:
Error using ==> sym.double at 25
DOUBLE cannot convert the input expression into a double array.
If the input expression contains a symbolic variable, use the VPA function instead.

Error in ==> trial at 5
A(i)=sym(strcat('a',num2str(i)));

cheers

### RE: Symbolic objects

Hmmm. Works for me. Try executing clear before you run it.

Otherwise there must be a difference in the behavior of matlab on our machines.  I have an old version Matlab 5.2

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