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ExpandTensors

Description

  • ExpandTensors expands out products leaving unexpended symbolic terms.
  • ExpandTensors[transformations] or ExpandTensors[[Simplifications: transformations]] applies transformations at each level of expand procedure.
  • ExpandTensors true will not expand expressions like (A_a^a + B_a^a)*(C_b^b + D_b^b).

Examples

Expand tensors in expressions: 

println ExpandTensors >> '(a+b)**10*(x_n + y_n)*(f_m - r_m)'.t

   > (a+b)**10*x_{n}*f_{m}+(a+b)**10*f_{m}*y_{n}-(a+b)**10*r_{m}*y_{n}-(a+b)**10*x_{n}*r_{m}


println ExpandTensors >> '(1 + x)**4*(A_a + B_a)'.t

   > (1 + x)**4*A_a + (1 + x)**4*B_a


println Expand >> '(1 + x)**4'.t

   > x**4+1+4*x**3+6*x**2+4*x


println Expand >> '(x + y)/z'.t

   > x/z+y/z

Expand relabels dummies when necessary: 

println Expand >> '(A_m^m + 1)**3'.t

   > 3*A_{m}^{m}*A_{a}^{a}+A_{m}^{m}*A_{a}^{a}*A_{b}^{b}+1+3*A_{b}^{b}

Expand does not go inside functions and denominators; ExpandAll does: 

println Expand >> 'f[(x + y)**2]'.t

   > f[(x + y)**2]

println ExpandAll >> 'f[(x + y)**2]'.t

   > f[x**2 + 2*x*y + y**2]

See also