Bucketsort init

bucketsort.c

+#include <stdio.h> 
+#include <stdlib.h> 
+#include <time.h> 
+#include <mpi.h> 
+#include <assert.h> 
+
+float *create_rand_nums(int num_elements) { 
+	float *rand_nums = (float *)malloc(sizeof(float) * num_elements); 
+	assert(rand_nums != NULL); 
+	int i; 
+	for (i = 0; i < num_elements; i++) { 
+		rand_nums[i] = (rand() / (float)RAND_MAX);
+	} 
+	return rand_nums; 
+} 
+ 
+float compute_avg(float *array, int num_elements) { 
+	float sum = 0.f; 
+	int i; 
+	for (i = 0; i < num_elements; i++) { 
+		sum += array[i]; 
+	} 
+	return sum / num_elements; 
+} 
+ 
+int main(int argc, char** argv) { 
+	if (argc != 2) { 
+		fprintf(stderr, "Usage: avg num_elements_per_proc\n"); 
+		exit(1); 
+	} 
+	MPI_Status Stat; 
+	
+	int num_elements_per_proc = atoi(argv[1]); 
+	srand(time(NULL)); 
+	 
+	MPI_Init(NULL, NULL); 
+	 
+	int world_rank; 
+	MPI_Comm_rank(MPI_COMM_WORLD, &world_rank); 
+	int world_size; 
+	MPI_Comm_size(MPI_COMM_WORLD, &world_size); 
+	int i, j, rc;
+	float inmsg[range];
+	
+	float *rand_nums = NULL; 
+	if (world_rank == 0) { 
+		rand_nums = create_rand_nums(num_elements_per_proc * world_size); 
+		int range = (RAND_MAX)/world_size;
+		float bucket[range];
+		int k;
+		for (i = 0; i < world_size; i++) {
+			k = 0;
+			for (j = 0; j < num_elements_per_proc * world_size; j++) {
+				if ((rand_nums[j] < i*range+range) && (rand_nums[j] => i*range)) {
+					bucket[k] = rand_nums[j];
+					k++;
+				} 
+			}
+			rc = MPI_Send(bucket, range, MPI_FLOAT, i, 1, MPI_COMM_WORLD); 
+		}
+		
+	} 
+	rc = MPI_Recv(inmsg, range, MPI_FLOAT, 0, 1, MPI_COMM_WORLD, &Stat); 
+	float t;
+	for (i = 1 ; i <= range - 1; i++) {
+		j = i;
+	 
+		while ( j > 0 && inmsg[j] < inmsg[j-1]) {
+		  t          = inmsg[j];
+		  inmsg[j]   = inmsg[j-1];
+		  inmsg[j-1] = t;
+	 
+		  j--;
+		}
+	 }
+	rc = MPI_Send(bucket, range, MPI_FLOAT, 0, 1, MPI_COMM_WORLD); 
+	 
+	if (world_rank == 0) { 
+		sub_avgs = (float *)malloc(sizeof(float) * world_size); 
+		assert(sub_avgs != NULL); 
+	} 
+	MPI_Gather(&sub_avg, 1, MPI_FLOAT, sub_avgs, 1, MPI_FLOAT, 0, MPI_COMM_WORLD); 
+ 
+	if (world_rank == 0) { 
+		k = 0;
+		for (i = 0; i < world_size; i++) {
+			rc = MPI_Recv(bucket, range, MPI_FLOAT, i, 1, MPI_COMM_WORLD, &Stat);
+			for (j = 0; j < range; j++) {
+				if (bucket[j] >= 0) {
+					rand_num[k] = bucket[j];
+					k++;
+				}
+			}
+			
+		}
+	} 
+	 
+	if (world_rank == 0) { 
+		free(rand_nums); 
+		free(sub_avgs); 
+	} 
+	free(sub_rand_nums); 
+	 
+	MPI_Barrier(MPI_COMM_WORLD); 
+	MPI_Finalize(); 
+}  
+