In the following code, why does it return the results as an integer.  Shouldn't it be showing me the full number such as 323.23456324324 which I should then be able to [math]::round(stuffhere,2)?

Get-WmiObject -class Win32_LogicalDisk | ForEach-Object {$_.Size = $_.Size/1GB; $_} | ForEach-Object {$_.FreeSpace = $_.FreeSpace/1GB; $_} | FT DeviceID,Size

If I do it into a regular foreach ($x in $variable {, it ends up working as I want so I can round it to the hundreth.

I guess the best way to do it anyways is:

Get-WmiObject -class Win32_LogicalDisk | Format-Table DeviceID,@{Label="Size";Expression={[math]::round($_.FreeSpace/1GB,2)}}

But still, I am curious as to why the first line doesn't work.

The reason is because you are trying to set values in the WMI object which has got its own ideas of what you can and can't do with it. :) Use Get-Member and its pretty obvious (which is why I use it so much):



So anyway, don't do that, it's bad practice and will get you in trouble. I would use calculated properties as you did with your second example, or use intermediate statements where you create new variables to store the values you need.

So taking a look at the following code:

$colItems = Get-WmiObject -class Win32_LogicalDisk

    foreach ($objItem in $colItems) {

            $objFreeSpace = $objItem.FreeSpace/1GB

            $objFreeSpace = [math]::round($objFreeSpace,2)
   }

How does $objFreeSpace | gm end up showing as System.Double and not as System.Management.ManagementObject#root\cimv2\Win32_LogicalDisk. 

isn't doing this the same as doing the foreach-object I initially did?

I am just not getting how foreach-object still tried to modify the object when it was in a state of System.Management.ManagementObject#root\cimv2\Win32_LogicalDisk while doing the foreach turned it into a System.Double which I could then round the way I wanted it to.