Select using other calculated properties - powershell

Question

Is there a way to use a calculated property in the same select statement for another calculated property. Or do you have to have another separate select for this?
I'm using PowerCLI from VMware to try to produce some memory stats (total, provisioned, % provisioned) for hosts.
get-vmhost | sort Parent |
select Parent, Name, #{Name="MemoryTotalGB";E={[math]::Round($_.MemoryTotalGB)}}, #{Name="MemoryProvisionedGB";Expression={$_ | get-vm | measure -sum MemoryGB | select -ExpandProperty Sum}} |
select Parent, Name, MemoryTotalGB, MemoryProvisionedGB, #{Name="MemoryProvisionedPercentage";E={[math]::Round($_.MemoryProvisionedGB / $_.MemoryTotalGB * 100)}} | ft
In the first select statement, I calculate the sum of VM memory running on the host as MemoryProvisionedGB. In the 2nd I do the % provisioned using this sum.
Is it possible to somehow reference the calculated property MemoryProvisionedGB in the first select statement to produce the % calculation?

Answer 1

Why don't you have the collection calculated just once (Although, BenH's ForEach-Object suggestion is more elegant)?
Get-VMHost |
Sort-Object -Property 'Parent' |
Select-Object -Property #(
'Parent'
'Name'
#{ N = 'MemoryTotalGB'
E = {[Math]::Round($PSItem.MemoryTotalGB)}
}
#{ N = 'MemoryProvisionedGB'
E = {($PSItem | Get-VM | Measure-Object -Sum 'MemoryGB').Sum}
}
#{ N = 'MemoryProvisionedPercentage'
E = {[Math]::Round(($PSItem | Get-VM | Measure-Object -Sum 'MemoryGB').Sum /
[Math]::Round($PSItem.MemoryTotalGB) * 100)
}
}
) | Format-Table

Answer 2

Rather than using calculated properties, you could use a ForEach-Object loop and create a [pscustomobject]. This would allow you to create several variables to reuse.
Get-VMHost |
ForEach-Object {
$MemoryTotalGB = [math]::Round($_.MemoryTotalGB)
$MemoryProvisionedGB = ($_ | Get-VM | Measure-Object -Sum MemoryGB).Sum
[PSCustomObject]#{
'Parent' = $_.Parent
'MemoryTotalGB' = $MemoryTotalGB
'MemoryProvisionedGB' = $MemoryProvisionedGB
'MemoryProvisionedPercentage' = [math]::Round($MemoryProvisionedGB / $MemoryTotalGB * 100)
}
} |
Sort-Object Parent |
Format-Table