Cadabra manual: Collect

collect_factors

Collect identical factors in a product.

Collect factors in a product that differ only by their exponent. Note that factors containing sub- or superscripted indices do not get collected (i.e. $A_m A^m$ does not get reduced to $(A_m)^2$).

ex:=A A B A B A;

$\displaystyle{}A A B A B A$

collect_factors(_);

$\displaystyle{}A^{4} B^{2}$

Arbitrary powers can be collected this way,

ex:=X X**(-1) X**(-4);

$\displaystyle{}X X^{-1} X^{-4}$

collect_factors(_);

$\displaystyle{}X^{-4}$

The exponent notation can be expanded again using expand_power.

ex:=X**4; expand_power(_);

$\displaystyle{}X^{4}$

$\displaystyle{}X X X X$