example

function undeploy
{
  Param(
		[parameter(Mandatory=$true, Position=0)]
		[ValidateSet("Production","Staging")]
		[String]
		$deploymentSlot,
		
		[parameter(Mandatory=$true, Position=1)]
		[String]
		$serviceName,
		
		[parameter(Mandatory=$true, Position=2)]
		#[ValidateScript({Test-Path $_})]
		[String]
		$pathToCertificate,
		
		[parameter(Mandatory=$true, Position=3)]
		[Guid]
		$subscriptionId
	)
	Process
	{
		$certificate = Get-Item $pathToCertificate
		
		Write-Host "Undeploying " $serviceName "(" $deploymentSlot ")"
		
		Get-HostedService $serviceName -Certificate $certificate -SubscriptionId $subscriptionId |
		Get-Deployment -Slot $deploymentSlot | 
		Remove-Deployment | 
		Get-OperationStatus -WaitToComplete
	}
}