Binary Subtraction
Continuing our look at maths functions in binary (hex is to come) lets have a quick look at subtraction
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| function Get-BinaryDifference {
param(
[string]$value1,
[string]$value2
)
## check valid binary numbers
## move this to a validation test
Test-Binary $value1
Test-Binary $value2
$diff = (ConvertTo-Decimal -inputvalue $value1 -binary) -`
(ConvertTo-Decimal -inputvalue $value2 -binary)
if ($diff -lt 0){Throw "Binary subtraction produces negative number"}
else {ConvertTo-Binary -inputvalue $diff}
} |
Always assume that value2 will be subtracted from value1 therefore value2 should be smaller.
The function is the same as the addition except we perform a subtraction :-)
And we check to see if we have a negative result. If so throw a wobbly and end the action.
These binary and hex functions will be the next module added to PSAM on codeplex