Data commit

Task/Ternary-logic/C/ternary-logic-1.c

@@ -0,0 +1,71 @@
+#include <stdio.h>
+
+typedef enum {
+  TRITTRUE,  /* In this enum, equivalent to integer value 0 */
+  TRITMAYBE, /* In this enum, equivalent to integer value 1 */
+  TRITFALSE  /* In this enum, equivalent to integer value 2 */
+} trit;
+
+/* We can trivially find the result of the operation by passing
+   the trinary values as indeces into the lookup tables' arrays. */
+trit tritNot[3] = {TRITFALSE , TRITMAYBE, TRITTRUE};
+trit tritAnd[3][3] = { {TRITTRUE, TRITMAYBE, TRITFALSE},
+                       {TRITMAYBE, TRITMAYBE, TRITFALSE},
+                       {TRITFALSE, TRITFALSE, TRITFALSE} };
+
+trit tritOr[3][3] = { {TRITTRUE, TRITTRUE, TRITTRUE},
+                      {TRITTRUE, TRITMAYBE, TRITMAYBE},
+                      {TRITTRUE, TRITMAYBE, TRITFALSE} };
+
+trit tritThen[3][3] = { { TRITTRUE, TRITMAYBE, TRITFALSE},
+                        { TRITTRUE, TRITMAYBE, TRITMAYBE},
+                        { TRITTRUE, TRITTRUE, TRITTRUE } };
+
+trit tritEquiv[3][3] = { { TRITTRUE, TRITMAYBE, TRITFALSE},
+                         { TRITMAYBE, TRITMAYBE, TRITMAYBE},
+                         { TRITFALSE, TRITMAYBE, TRITTRUE } };
+
+/* Everything beyond here is just demonstration */
+
+const char* tritString[3] = {"T", "?", "F"};
+
+void demo_binary_op(trit operator[3][3], const char* name)
+{
+  trit operand1 = TRITTRUE; /* Declare. Initialize for CYA */
+  trit operand2 = TRITTRUE; /* Declare. Initialize for CYA */
+
+  /* Blank line */
+  printf("\n");
+
+  /* Demo this operator */
+  for( operand1 = TRITTRUE; operand1 <= TRITFALSE; ++operand1 )
+  {
+    for( operand2 = TRITTRUE; operand2 <= TRITFALSE; ++operand2 )
+    {
+      printf("%s %s %s: %s\n", tritString[operand1],
+                               name,
+                               tritString[operand2],
+                               tritString[operator[operand1][operand2]]);
+    }
+  }
+
+}
+
+int main()
+{
+  trit op1 = TRITTRUE; /* Declare. Initialize for CYA */
+  trit op2 = TRITTRUE; /* Declare. Initialize for CYA */
+
+  /* Demo 'not' */
+  for( op1 = TRITTRUE; op1 <= TRITFALSE; ++op1 )
+  {
+    printf("Not %s: %s\n", tritString[op1], tritString[tritNot[op1]]);
+  }
+  demo_binary_op(tritAnd, "And");
+  demo_binary_op(tritOr, "Or");
+  demo_binary_op(tritThen, "Then");
+  demo_binary_op(tritEquiv, "Equiv");
+
+
+  return 0;
+}

Task/Ternary-logic/C/ternary-logic-2.c

@@ -0,0 +1,36 @@
+#include <stdio.h>
+
+typedef enum { t_F = -1, t_M, t_T } trit;
+
+trit t_not  (trit a) { return -a; }
+trit t_and  (trit a, trit b) { return a < b ? a : b; }
+trit t_or   (trit a, trit b) { return a > b ? a : b; }
+trit t_eq   (trit a, trit b) { return a * b; }
+trit t_imply(trit a, trit b) { return -a > b ? -a : b; }
+char t_s(trit a) { return "F?T"[a + 1]; }
+
+#define forall(a) for(a = t_F; a <= t_T; a++)
+void show_op(trit (*f)(trit, trit), const char *name) {
+	trit a, b;
+	printf("\n[%s]\n    F ? T\n  -------", name);
+	forall(a) {
+		printf("\n%c |", t_s(a));
+		forall(b) printf(" %c", t_s(f(a, b)));
+	}
+	puts("");
+}
+
+int main(void)
+{
+	trit a;
+
+	puts("[Not]");
+	forall(a) printf("%c | %c\n", t_s(a), t_s(t_not(a)));
+
+	show_op(t_and,   "And");
+	show_op(t_or,    "Or");
+	show_op(t_eq,    "Equiv");
+	show_op(t_imply, "Imply");
+
+	return 0;
+}

Task/Ternary-logic/C/ternary-logic-3.c

@@ -0,0 +1,55 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef double half_truth, maybe;
+
+inline maybe not3(maybe a) { return 1 - a; }
+
+inline maybe
+and3(maybe a, maybe b) { return a * b; }
+
+inline maybe
+or3(maybe a, maybe b) { return a + b - a * b; }
+
+inline maybe
+eq3(maybe a, maybe b) { return 1 - a - b + 2 * a * b; }
+
+inline maybe
+imply3(maybe a, maybe b) { return or3(not3(a), b); }
+
+#define true3(x) ((x) * RAND_MAX > rand())
+#define if3(x) if (true3(x))
+
+int main()
+{
+	maybe roses_are_red = 0.25; /* they can be white or black, too */
+	maybe violets_are_blue = 1; /* aren't they just */
+	int i;
+
+	puts("Verifying flowery truth for 40 times:\n");
+
+	puts("Rose is NOT red:"); /* chance: .75 */
+	for (i = 0; i < 40 || !puts("\n"); i++)
+		printf( true3( not3(roses_are_red) ) ? "T" : "_");
+
+	/* pick a rose and a violet; */
+	puts("Rose is red AND violet is blue:");
+	/* chance of rose being red AND violet being blue is .25 */
+	for (i = 0; i < 40 || !puts("\n"); i++)
+		printf( true3( and3(roses_are_red, violets_are_blue) )
+			? "T" : "_");
+
+	/* chance of rose being red OR violet being blue is 1 */
+	puts("Rose is red OR violet is blue:");
+	for (i = 0; i < 40 || !puts("\n"); i++)
+		printf( true3( or3(roses_are_red, violets_are_blue) )
+			? "T" : "_");
+
+	/* pick two roses; chance of em being both red or both not red is .625 */
+	puts("This rose is as red as that rose:");
+	for (i = 0; i < 40 || !puts("\n"); i++)
+		if3(eq3(roses_are_red, roses_are_red)) putchar('T');
+		else putchar('_');
+
+	return 0;
+}