Ein Anderssono
54d2fecee0
- Added implementations for: bash, brainfuck, c, cpp, crystal, csharp, d, dart, elixir, erlang, fortran, go, haskell, java, javascript, julia, kotlin, objective-c, scala, typescript, lua, nim, odin, perl, php, python, r, ruby, rust, swift, zig, assembly, vimscript, wolfram - All implementations use Machin's formula: π/4 = 4*arctan(1/5) - arctan(1/239) - Build system with ./build.sh, test system with ./test.sh - Performance testing with ./run_all.sh - Comprehensive README.md explaining performance differences - Test framework verifies correctness against known π values
63 lines
1.0 KiB
Crystal
63 lines
1.0 KiB
Crystal
require "big"
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def pow10(exp : Int32) : BigInt
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result = BigInt.new(1)
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exp.times do
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result *= 10
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end
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result
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end
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def arctan(x : Int32, decimals : Int32) : BigInt
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scale = pow10(decimals + 10)
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x_squared = x * x
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term = scale // x
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result = BigInt.new(0)
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n = 0
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while term != 0
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divisor = 2 * n + 1
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contrib = term // divisor
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if n % 2 == 0
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result += contrib
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else
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result -= contrib
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end
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term = term // x_squared
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n += 1
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end
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result
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end
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def calculate_pi(decimals : Int32) : String
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atan1_5 = arctan(5, decimals)
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atan1_239 = arctan(239, decimals)
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# pi = 16*arctan(1/5) - 4*arctan(1/239)
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pi = 16 * atan1_5 - 4 * atan1_239
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pi_str = pi.to_s
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# Format with decimal point
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result = "3."
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start = 1
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decimals.times do |i|
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if start + i < pi_str.size
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result += pi_str[start + i].to_s
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else
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result += "0"
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end
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end
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result
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end
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# Main
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decimals = ARGV.size > 0 ? ARGV[0].to_i? || 100 : 100
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puts calculate_pi(decimals) |