June 2018 Update

Task/Averages-Pythagorean-means/Modula-2/averages-pythagorean-means.mod2

@@ -0,0 +1,79 @@
+MODULE PythagoreanMeans;
+FROM FormatString IMPORT FormatString;
+FROM LongMath IMPORT power;
+FROM LongStr IMPORT RealToStr;
+FROM Terminal IMPORT WriteString,WriteLn,ReadChar;
+
+PROCEDURE ArithmeticMean(numbers : ARRAY OF LONGREAL) : LONGREAL;
+VAR
+    i,cnt : CARDINAL;
+    mean : LONGREAL;
+BEGIN
+    mean := 0.0;
+    cnt := 0;
+    FOR i:=0 TO HIGH(numbers) DO
+        mean := mean + numbers[i];
+        INC(cnt);
+    END;
+    RETURN mean / LFLOAT(cnt)
+END ArithmeticMean;
+
+PROCEDURE GeometricMean(numbers : ARRAY OF LONGREAL) : LONGREAL;
+VAR
+    i,cnt : CARDINAL;
+    mean : LONGREAL;
+BEGIN
+    mean := 1.0;
+    cnt := 0;
+    FOR i:=0 TO HIGH(numbers) DO
+        mean := mean * numbers[i];
+        INC(cnt);
+    END;
+    RETURN power(mean, 1.0 / LFLOAT(cnt))
+END GeometricMean;
+
+PROCEDURE HarmonicMean(numbers : ARRAY OF LONGREAL) : LONGREAL;
+VAR
+    i,cnt : CARDINAL;
+    mean : LONGREAL;
+BEGIN
+    mean := 0.0;
+    cnt := 0;
+    FOR i:=0 TO HIGH(numbers) DO
+        mean := mean + ( 1.0 / numbers[i]);
+        INC(cnt);
+    END;
+    RETURN LFLOAT(cnt) / mean
+END HarmonicMean;
+
+
+CONST Size = 10;
+TYPE DA = ARRAY[1..Size] OF LONGREAL;
+
+VAR
+    buf : ARRAY[0..63] OF CHAR;
+    array : DA;
+    arithmetic,geometric,harmonic : LONGREAL;
+BEGIN
+    array := DA{1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0};
+
+    arithmetic := ArithmeticMean(array);
+    geometric := GeometricMean(array);
+    harmonic := HarmonicMean(array);
+
+    WriteString("A = ");
+    RealToStr(arithmetic, buf);
+    WriteString(buf);
+    WriteString(" G = ");
+    RealToStr(geometric, buf);
+    WriteString(buf);
+    WriteString(" H = ");
+    RealToStr(harmonic, buf);
+    WriteString(buf);
+    WriteLn;
+
+    FormatString("A >= G is %b, G >= H is %b\n", buf, arithmetic >= geometric, geometric >= harmonic);
+    WriteString(buf);
+
+    ReadChar
+END PythagoreanMeans.