====== ExpandDenominator ======
----

====Description====
  * ''ExpandDenominator'' expands out products and powers that appear as denominators in expressions.
  
  
  * ''ExpandDenominator[transformations]'' additionally applies transformations at each level of expand procedure. 


  * ''ExpandDenominator'' works only on negative integer powers.


  * ''ExpandDenominator'' applies only to the top level in expressions.


====Examples====
----
Expand the denominator of a fraction:
<sxh groovy; gutter: false>
println ExpandDenominator  >> '(x - 1) * (x - 2)/((x - 3) * (x - 4))'.t
</sxh>
<sxh plain; gutter: false>
   > (x-1)*(x-2)/(x**2 - 7*x +12)
</sxh>

----

Expand the denominator in each term:
<sxh groovy; gutter: false>
println ExpandDenominator  >> '1/(1 + x) + 2/(2 + x)**2 + 3/(3 + x)**3'.t
</sxh>
<sxh plain; gutter: false>
   > 1/(1 + x) + 2/(4 + 4*x + x**2) + 3/(27 + 27*x + 9*x**2 + x**3)
</sxh>

----

====Details====

''ExpandDenominator[transformations]'' additionally applies transformations at each level of expand procedure:
<sxh groovy; gutter: false>
def t = '1/((k_a - p_a)*(k^a + p^a))'.t
println ExpandDenominator['k_a*k^a = 0'.t] >> t
</sxh>
<sxh plain; gutter: false>
   > -1/(p_a*p^a)
</sxh>
For more examples see [[documentation:ref:expand#details|Expand]].

====See also====
  * Related guides: [[documentation:guide:applying_and_manipulating_transformations]], [[documentation:guide:list_of_transformations]]
  * Related transformations: [[documentation:ref:expand]], [[documentation:ref:expandnumerator]], [[documentation:ref:expandall]]
  * JavaDocs: [[http://api.redberry.cc/redberry/1.1.9/java-api/cc/redberry/core/transformations/expand/ExpandDenominatorTransformation.html|ExpandDenominatorTransformation]]
  * Source code: [[https://bitbucket.org/redberry/redberry/src/tip/core/src/main/java/cc/redberry/core/transformations/expand/ExpandDenominatorTransformation.java|ExpandDenominatorTransformation.java]]