PowerShell/Scripts/list-pi.ps1
2023-04-21 19:38:29 +02:00

74 lines
1.6 KiB
PowerShell
Executable File

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