MATLAB: Can a Comma Separated List be Generated Directly from a sym Array

Question

Can a comma separated list be generated directly from a sym array for use as input to a sym function?

>> xvar=sym('x',[1 4])
 
xvar =
 
[ x1, x2, x3, x4]
 
>> yvar=sym('y',[1 4])
 
yvar =
 
[ y1, y2, y3, y4]
 
>> f(xvar)=sum(xvar)
 
f(x1, x2, x3, x4) =
 
x1 + x2 + x3 + x4
 
>> f(yvar)
Error using symfun/subsref (line 177)
Symbolic function expected 4 input arguments but received 1.
 
>> temp=num2cell(yvar);
>> f(temp{:})
 
ans =
 
y1 + y2 + y3 + y4
 

Baically, is there a way evaluate f at the elements of yvar without having to create the temp variable, as needed for generailized code where the lengths of xvar and yvar are not known ahead of time?

Answer 1

Can a comma separated list be generated directly from a sym array for use as input to a sym function?

NO. But you can do it without an explicit temporary variable.

xvar=sym('x',[1 4]);
yvar=sym('y',[1 4]);
f(xvar) = sum(xvar);
f(struct('v', num2cell(yvar)).v)
ans =