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- //
- // BinTest
- //
- // This program tests a random number generator by running it n times
- // with m bins for sorting over the interval [0, 1].
- //
-
-
- #import "Random.h"
- #import <math.h>
- #import <stdio.h>
- #import <stdlib.h>
-
-
- #define FUNC doublepeakfunc
-
-
- #define DEFAULT_N 1000
- #define DEFAULT_M 20
-
-
- #define MAX_BAR 40
-
-
- #define TAN_PI 3.14159267
- #define TAN_2DIVPI (2.0 / TAN_PI)
-
- double tanfunc(double x)
- {
- // return (tan(TAN_2DIVPI * x - 0.5) + 0.5);
- return (1 + tan((x - 0.5) / TAN_PI)) / 2.0;
- }
-
-
- #define SINONE 0.8414709848
-
- double sinfunc(double x)
- {
- return (sin(x) / SINONE);
- }
-
-
- double linefunc(double x)
- {
- return (x);
- }
-
-
- double squarefunc(double x)
- {
- return (x * x);
- }
-
-
- double parafunc(double x)
- {
- double y = x - 1.0;
-
- return (1 - (y * y));
- }
-
-
- double doublepeakfunc(double x)
- {
- return (1 + sin((x / TAN_PI) - 0.5)) / 2.0;
- }
-
-
- int main(int argc, char *argv[])
- {
- id myRand; // Random number generator.
- int n; // Quantity of numbers to generate.
- int m; // Number of bins in which to sort them.
- int max; // Size of largest bin.
- int i; // Generic loop variable.
- int j; // Generic loop variable.
- double x; // The random number.
- int slot; // The sorted position of a number.
- int barsize; // The length of a result bar.
- int *bin; // The bin array (dynamically allocated).
-
- myRand = [[Random alloc] init];
-
- switch(argc) {
- case 2:
- sscanf(argv[1], "%d", &n);;
- m = DEFAULT_M;
- break;
- case 3:
- sscanf(argv[1], "%d", &n);;
- sscanf(argv[2], "%d", &m);;
- break;
- default:
- n = DEFAULT_N;
- m = DEFAULT_M;
- break;
- }
-
- //
- // Allocate and initialize slot array:
- //
-
- bin = (int *)malloc(m * sizeof(int));
- for(i = 0; i < m; i++)
- bin[i] = 0;
-
- //
- // Make n random numbers:
- //
-
- for(i = 0; i < n; i++) {
- x = [myRand gaussian];
-
- slot = (int)floor(x * m);
- if((slot >= 0) && (slot < m)) { // If it is in range,
- if((++bin[slot]) > max) { // count it.
- max = bin[slot];
- }
- }
- }
-
- //
- // Print the results:
- //
-
- for(i = 0; i < m; i++) {
- printf("%1.6f - %1.6f: %6d:", i * (1.0 / m), (i + 1) * (1.0 / m), bin[i]);
-
- barsize = (int)((double)bin[i] / ((double)max / (double)MAX_BAR));
- for(j = 0; j < barsize; j++)
- printf("*");
- printf("\n");
- }
-
- printf("Max = %d\n\n", max);
-
- //
- // Clean up:
- //
-
- free(bin);
-
- //
- // Return to caller:
- //
-
- return 0;
- }
-
-
- //
- // End of file.
- //