function variable = getVariableFromAlgebricEquation(variableName, variablesStruct, equation)
  % v1^e1 * ... * vn^en = 1
  product = 1 ;
  numberOfVariables = length(equation.variableNames) ;
  for i = 1 : numberOfVariables
    variableiName = equation.variableNames(i) ;
    exponenti     = equation.exponents(i) ;
    if isequal(variableiName, variableName)
      exponentVariable = exponenti ;
    else
      product = product * variablesStruct.(variableiName) ^ exponenti ;
    end
  end
  variable = 1 / product ^ ( 1 / exponentVariable ) ;
end