Operator -gt and -le / Problem with negative numbers - powershell

Question

i have the following code snippet where i change the values in a column (named G) of a csv to Y if the integer value is greater then 1 and to N if it is equal to 1 and smaller.
ForEach-Object {if ($_.G -gt '1') {$_.G = 'Y'} if ($_.G -le '1') {$_.G = 'N'} $_}
It works fine with the exception of negative numbers. I always get a Y. I don't have any idea. Example data:
F,G
item1, -58
item2, -77
item3, 562
Does anyone have an idea?
Regards, Hubertus

Answer 1

In order to evaluate the $_.G property as a number you need to specify the type as [int]. Example using your code:
$testObject = New-Object PSObject -Property #{
G='-1'
}
$testObject| %{
if ([int]$_.G -gt 1)
{
$out = "{0} is greater than 1" -f $_.G
Write-Host $out -ForegroundColor Green
[string]$_.G = "Y"
}
elseif ([int]$_.G -le 1)
{
$out = "{0} is Less than 1" -f $_.G
Write-Host $out -ForegroundColor Green
[string]$_.G = "N"
}
}
Note: In order to assign $_.G as a string you have to change the type to [string]. In my opinion, I would use another property to indicate "Y/N" instead of flipping the type back and forth on the property.

Answer 2

The left side of -le or -gt controls the type for both sides, int32 (integer) in this case. You probably want an else in there, to not look at the G again after changing it.
'G
-1
1
2' |
convertfrom-csv |
ForEach-Object {
if (1 -le $_.G)
{$_.G = 'Y'}
else
{$_.G = 'N'}
$_
}
G
-
N
Y
Y