code: public Observable<AutoScaleRun> evaluateAutoScaleAsync(String poolId, String autoScaleFormula) {
          return evaluateAutoScaleWithServiceResponseAsync(poolId, autoScaleFormula).map(new Func1<ServiceResponseWithHeaders<AutoScaleRun, PoolEvaluateAutoScaleHeaders>, AutoScaleRun>() {
              @Override
              public AutoScaleRun call(ServiceResponseWithHeaders<AutoScaleRun, PoolEvaluateAutoScaleHeaders> response) {
                  return response.body();
              }
          });
      }
docs: Gets the result of evaluating an automatic scaling formula on the pool.
  This API is primarily for validating an autoscale formula, as it simply returns the result without applying the formula to the pool. The pool must have auto scaling enabled in order to evaluate a formula.
  
  @param poolId The ID of the pool on which to evaluate the automatic scaling formula.
  @param autoScaleFormula The formula for the desired number of compute nodes in the pool. The formula is validated and its results calculated, but it is not applied to the pool. To apply the formula to the pool, 'Enable automatic scaling on a pool'. For more information about specifying this formula, see Automatically scale compute nodes in an Azure Batch pool (https://azure.microsoft.com/en-us/documentation/articles/batch-automatic-scaling).
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the AutoScaleRun object