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75 lines
1.7 KiB
PowerShell
Executable File
75 lines
1.7 KiB
PowerShell
Executable File
<#
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.SYNOPSIS
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Writes PI
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.DESCRIPTION
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This PowerShell script calculates and writes the digits of the mathematical constant PI.
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.PARAMETER digits
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Specifies the number of digits to list (1000 by default)
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.EXAMPLE
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PS> ./write-pi.ps1
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3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342...
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.LINK
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https://github.com/fleschutz/PowerShell
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.NOTES
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Author: Markus Fleschutz | License: CC0
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#>
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param([int]$digits = 1000)
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function Write-Pi ( $digits ) {
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$Big = [bigint[]](0..10)
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$ndigits = 0
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$q = $t = $k = $Big[1]
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$r = $Big[0]
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$l = $n = $Big[3]
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# calculate first digit
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$nr = ( $Big[2] * $q + $r ) * $l
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$nn = ( $q * ( $Big[7] * $k + $Big[2] ) + $r * $l ) / ( $t * $l )
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$q *= $k
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$t *= $l
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$l += $Big[2]
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$k = $k + $Big[1]
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$n = $nn
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$r = $nr
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Write-Host "$($n)." -noNewline
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$ndigits++
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$nr = $Big[10] * ( $r - $n * $t )
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$n = ( ( $Big[10] * ( 3 * $q + $r ) ) / $t ) - 10 * $n
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$q *= $Big[10]
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$r = $nr
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while ($ndigits -lt $digits) {
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if ($Big[4] * $q + $r - $t -lt $n * $t) {
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Write-Host "$n" -noNewline
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$ndigits++
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$nr = $Big[10] * ( $r - $n * $t )
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$n = ( ( $Big[10] * ( 3 * $q + $r ) ) / $t ) - 10 * $n
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$q *= $Big[10]
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$r = $nr
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} else {
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$nr = ( $Big[2] * $q + $r ) * $l
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$nn = ( $q * ( $Big[7] * $k + $Big[2] ) + $r * $l ) / ( $t * $l )
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$q *= $k
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$t *= $l
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$l += $Big[2]
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$k = $k + $Big[1]
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$n = $nn
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$r = $nr
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}
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}
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Write-Host "... ($digits digits)"
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}
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try {
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Write-Pi $digits
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exit 0 # success
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} catch {
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"⚠️ Error in line $($_.InvocationInfo.ScriptLineNumber): $($Error[0])"
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exit 1
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}
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