FACTOR_declaration INDEX

FACTOR _ _ _ _ _ _ _ _ _ _ _ _ declaration

When a kernel is declared by factor, all terms involving fixed powers of that kernel are printed as a product of the fixed powers and the rest of the terms.

syntax:

factor<kernel> {,<kernel>}*

<kernel> must be a kernel or a list of kernels.

examples:


a := (x + y + z)**2; 

        2                    2            2
  A := X  + 2*X*Y + 2*X*Z + Y  + 2*Y*Z + Z  


factor y; 

a; 

   2                  2            2
  Y  + 2*Y*(X + Z) + X  + 2*X*Z + Z  


factor sin(x); 

c := df(sin(x)**4*x**2*z,x); 

               4               3         2
  C := 2*SIN(X) *X*Z + 4*SIN(X) *COS(X)*X *Z 


remfac sin(x); 

c; 

          3
  2*SIN(X) *X*Z*(2*COS(X)*X + SIN(X))

Use the factor declaration to display variables of intere st so that you can see their powers more clearly, as shown in the example. Remove this special treatment with the declaration remfac. The factor declaration is only effective when the switch pri is on.

The factor declaration is not a factoring command; to factor expressions use the factor switch or the factorize command.

The factor declaration is helpful in such cases as Taylor polynomials where the explicit powers of the variable are expected at the top level, not buried in various factored forms.

Note that factor does not affect the order of its arguments. You should also use order if this is important.