Create a calculated property
Documentation: Microsoft Learn
Select-Object accepts a hashtable with an n key naming the new column and an e key holding a script block that computes its value.
The script
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Get-Process | Select-Object Name,@{ Name = "MemoryMB"; Expression = { [math]::Round($_.WorkingSet64/1MB, 1)} }- Stage 1Get-Process
Positional values or no named parameters - Stage 2Select-Object
Positional values or no named parameters
How it works
Select-Object accepts a hashtable with an n key naming the new column and an e key holding a script block that computes its value. Inside that block $_ is the current object, so WorkingSet64 gets divided by 1MB and rounded to one decimal, appearing in the output as MemoryMB.
Adapting it
Those n and e keys are shorthand for Name and Expression, and spelling them out in full makes the intent obvious to whoever reads the script a year from now.
If the result is unexpected
A calculated property is blank, repeated or rounded unexpectedly.
The expression may reference the wrong property, use the wrong units or capture a variable instead of the current object.
- Evaluate the calculation on a single known object and confirm the units and numeric type.
Validate the result
The calculated value agrees with a manually checked sample.
Keep the check reliable
Keep the unrounded numeric value for calculations and round only when the report requires it.
