107 lines
1.6 KiB
Markdown
107 lines
1.6 KiB
Markdown
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###PI Calculation
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Calculates PI to a certain degree with the Monte Carlo algorithm
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```textfunge
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program PICalc : display[256, 256]
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const
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// WIDTH = HEIGHT = 4^SIZE
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int SIZE := 4;
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// Total Count
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int COUNT := 65536;
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// After n Steps print out intermediate result
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int STEPS := 4096;
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global
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int hit;
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int miss;
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var
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int i;
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begin
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hit = 0;
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miss = 0;
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for(i = 0; i < COUNT; i++) do
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drop();
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if (i % STEPS == 0) then
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output();
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end
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end
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output();
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end
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void output()
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begin
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// PI := (4 * hit)/(total)
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outf "PI = ", (4*hit), "/", (hit+miss), " = ", floatDiv(4 * hit, miss + hit), "\r\n";
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end
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void drop()
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var
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int x, y;
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char c;
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begin
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x = RAND[SIZE];
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y = RAND[SIZE];
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c = display[x, y];
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display[x, y] = 'X';
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if (c == '#') then
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hit++;
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elsif (c == ' ') then
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miss++;
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else
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out "FATAL ERROR 0x01";
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end
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display[x, y] = c;
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end
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// Gives a string containing a/b as float back
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char[10] floatDiv(int a, int b)
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var
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char[10] result;
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int mantissa;
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int pos := 0;
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begin
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mantissa = a / b;
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repeat
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if (pos == 10) then
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return result;
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end
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result[pos++] = (char)((int)'0' + (mantissa % 10));
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mantissa /= 10;
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until (mantissa == 0)
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if (pos == 10) then
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return result;
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end
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result[pos++] = ',';
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for(;;) do
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if (pos == 10) then
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return result;
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end
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a %= b;
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a *= 10;
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result[pos++] = (char)((int)'0' + (a / b));
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end
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return result;
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end
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end
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```
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> **Note:** This program needs a special initial display value to work - see the download to execute it.
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> **Note:** *This and other examples are included in the BefunGen download*
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