Fix for fast file reading, Console output improvements

datasets/Stanford Large Network Dataset Collection/README.md

@@ -6,18 +6,3 @@ More details about the datasets can be found in the table bellow.
 | ----------- | ----------- | ----------- | ----------- | ----------- |
 | web-Google | "web-Google" | 875,713 | 5,105,039 | [link](https://snap.stanford.edu/data/web-Google.html) |
 | wiki-Talk | "wiki-Talk" | 2,394,385 | 5,021,410 | [link](https://snap.stanford.edu/data/wiki-Talk.html) |
-
-### Adjustments made to the datasets:
-The datasets had four (4) lines of meta-data at the beginning of the files and the data were saved in a form that had one edge per line following the pattern "`linkFrom\tlinkTo\n`", like so:
-```
-linkFrom    linkTo
-linkFrom    linkTo
-...
-```
-A program in C was written to discard the meta-data lines and transform the pattern in a new one that has all the out-links of a page in a single row, like so:
-```
-page_1: linkTo_1 linkTo_2 linkTo_3 ...
-page_2: linkTo_1 ...
-```
-
-The program is provided in this repository, under the pathname: `/datasets/Stanford Large Network Dataset Collection/graphToAdjacencyList.c`.

datasets/Stanford Large Network Dataset Collection/graphToAdjacencyList.c

@@ -1,90 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-typedef struct pair {
-	int from;
-	int to;
-} Pair;
-
-int main(int argc, char const *argv[]) {
-	if (argc != 2) {
-		printf("Usage: ./graphToAdjacencyList <graphFile>\n");
-		exit(EXIT_FAILURE);
-	}
-
-	FILE *graphFile = fopen(argv[1], "r");
-	if (!graphFile) {
-		printf("Error opening file \n");
-		exit(EXIT_FAILURE);
-	}
-
-	char buffer[512];
-	// Skips the first two lines
-	fgets(buffer, 512, graphFile);
-	fgets(buffer, 512, graphFile);
-
-	// Third line has the numbers of nodes and edges, we need to parse them.
-	int numberOfNodes = 0, numberOfEdges;
-	fgets(buffer, 512, graphFile);
-
-	char *token = strtok(buffer, " ");
-	int getNodes = 0, getEdges = 0;
-
-	while (token != NULL) {
-		if (strcmp(token, "Nodes:") == 0) {
-			getNodes = 1;
-		} else if (getNodes == 1) {
-			numberOfNodes = atoi(token);
-			getNodes = 0;
-		} else if (strcmp(token, "Edges:") == 0) {
-			getEdges = 1;
-		} else if (getEdges == 1) {
-			numberOfEdges = atoi(token);
-			break;
-		}
-		token = strtok (NULL, " ,.-");
-	}
-
-	// Skips the fourth line
-	fgets(buffer, 512, graphFile);
-
-	Pair **edges = (Pair **) malloc(numberOfEdges * sizeof(Pair *));
-	printf("Reading edges from file...\n");
-	for (int i=0; i<numberOfEdges; i++) {
-		edges[i] = (Pair *) malloc(sizeof(Pair));
-
-		int f_from = 0, f_to = 0;
-		if (!fscanf(graphFile, "%d %d", &f_from, &f_to)) {
-			break;
-		}
-
-		edges[i]->from = f_from;
-		edges[i]->to = f_to;
-	}
-
-
-	FILE *adjacentListFile = fopen("adjacentListCreated", "w");
-	int index = 0;
-
-	printf("\nWriting nodes to file...\n");
-	for (int i=0; i<numberOfNodes; ++i) {
-		int hasOutlinks = 0;
-
-		fprintf(adjacentListFile, "%d: ", i);
-
-		while (index < numberOfEdges && edges[index]->from == i) {
-			fprintf(adjacentListFile, "%d ", edges[index]->to);
-			if (!hasOutlinks) hasOutlinks = 1;
-			++index;
-		}
-
-		if (!hasOutlinks) {
-			fprintf(adjacentListFile, "-1 ");
-		}
-
-		fprintf(adjacentListFile, "\n");
-	}
-
-	return 0;
-}

serial/serial_gs_pagerank.c

@@ -9,6 +9,7 @@ double seq_time;
 int main(int argc, char **argv) {
 	SparseMatrix transitionMatrix;
 	double *pagerankVector;
+	bool convergenceStatus;
 	Parameters parameters;
 
 	transitionMatrix = createSparseMatrix();
@@ -20,10 +21,17 @@ int main(int argc, char **argv) {
 	// Starts wall-clock timer
 	gettimeofday (&startwtime, NULL);
 
-	int iterations = pagerank(&transitionMatrix, &pagerankVector, parameters);
+	int iterations = pagerank(&transitionMatrix, &pagerankVector,
+		&convergenceStatus, parameters);
 	if (parameters.verbose) {
-		printf("\n----- Results -----\
-			\nTotal iterations = %d\n", iterations);
+		printf(ANSI_COLOR_YELLOW "\n----- RESULTS -----\n" ANSI_COLOR_RESET);
+		if (convergenceStatus) {
+			printf(ANSI_COLOR_GREEN "Pagerank converged after %d iterations!\n" \
+				ANSI_COLOR_RESET, iterations);
+		} else {
+			printf(ANSI_COLOR_RED "Pagerank did not converge after max number of" \
+				" iterations (%d) was reached!\n" ANSI_COLOR_RESET, iterations);
+		}
 	}
 
 	// Stops wall-clock timer

serial/serial_gs_pagerank_functions.c

@@ -9,11 +9,12 @@ const char *ARGUMENT_OUTPUT_FILENAME = "-o";
 
 const int NUMERICAL_BASE = 10;
 char *DEFAULT_OUTPUT_FILENAME = "pagerank_output";
-const int MAX_PAGE_LINKS_TEXT_SIZE = 4096;
+const int FILE_READ_BUFFER_SIZE = 4096;
 
 // ==================== PAGERANK ====================
 
-int pagerank(SparseMatrix *transitionMatrix, double **pagerankVector, Parameters parameters) {
+int pagerank(SparseMatrix *transitionMatrix, double **pagerankVector,
+	bool *convergenceStatus, Parameters parameters) {
 	int iterations = 0;
 	double delta,
 	*vectorDifference = (double *) malloc(parameters.numberOfPages * sizeof(double)),
@@ -22,6 +23,7 @@ int pagerank(SparseMatrix *transitionMatrix, double **pagerankVector, Parameters
 	**linksFromConvergedPages = (double **) malloc(parameters.numberOfPages * sizeof(double *)),
 	*linksFromConvergedPagesPagerankVector = (double *) malloc(parameters.numberOfPages * sizeof(double));
 	bool *converganceMatrix = (bool *) malloc(parameters.numberOfPages * sizeof(bool));
+	*convergenceStatus = false;
 
 	for (int i=0; i<parameters.numberOfPages; ++i) {
 		convergedPagerankVector[i] = 0;
@@ -35,7 +37,7 @@ int pagerank(SparseMatrix *transitionMatrix, double **pagerankVector, Parameters
 	}
 
 	if (parameters.verbose) {
-		printf("\n----- Starting iterations -----\n");
+		printf(ANSI_COLOR_YELLOW "\n----- Starting iterations -----\n" ANSI_COLOR_RESET);
 	}
 
 	do {
@@ -57,6 +59,9 @@ int pagerank(SparseMatrix *transitionMatrix, double **pagerankVector, Parameters
 			vectorDifference[i] = (*pagerankVector)[i] - previousPagerankVector[i];
 		}
 		delta = vectorNorm(vectorDifference, parameters.numberOfPages);
+		if (delta < parameters.convergenceCriterion) {
+			*convergenceStatus = true;
+		}
 
 		if (iterations && !iterations % 10) {
 			for (int i=0; i<parameters.numberOfPages; ++i) {
@@ -88,8 +93,12 @@ int pagerank(SparseMatrix *transitionMatrix, double **pagerankVector, Parameters
 		}
 
 		++iterations;
-		printf("Iteration %d: delta = %f\n", iterations, delta);
-	} while (delta > parameters.convergenceCriterion &&
+		if (iterations%2) {
+			printf(ANSI_COLOR_BLUE "Iteration %d: delta = %f\n" ANSI_COLOR_RESET, iterations, delta);
+		} else {
+			printf(ANSI_COLOR_CYAN "Iteration %d: delta = %f\n" ANSI_COLOR_RESET, iterations, delta);
+		}
+	} while (!*convergenceStatus &&
 		(parameters.maxIterations == 0 || iterations < parameters.maxIterations));
 
 	if (!parameters.history) {
@@ -112,22 +121,22 @@ void initialize(SparseMatrix *transitionMatrix,
 
 	// Reads web graph from file
 	if ((*parameters).verbose) {
-		printf("----- Reading graph from file -----\n");
+		printf(ANSI_COLOR_YELLOW "----- Reading graph from file -----\n" ANSI_COLOR_RESET);
 	}
 	generateNormalizedTransitionMatrixFromFile(transitionMatrix, parameters);
 
 	// Outputs the algorithm parameters to the console
 	if ((*parameters).verbose) {
-		printf("\n----- Running with parameters -----\
-			\nNumber of pages: %d", (*parameters).numberOfPages);
+		printf(ANSI_COLOR_YELLOW "\n----- Running with parameters -----\n" ANSI_COLOR_RESET\
+			"Number of pages: %d", (*parameters).numberOfPages);
 		if (!(*parameters).maxIterations) {
 			printf("\nMaximum number of iterations: inf");
 		} else {
 			printf("\nMaximum number of iterations: %d", (*parameters).maxIterations);
 		}
-		printf("\nConvergence criterion: %f\
-			\nDamping factor: %f\
-			\nGraph filename: %s\n", (*parameters).convergenceCriterion,
+		printf("\nConvergence criterion: %f" \
+			"\nDamping factor: %f" \
+			"\nGraph filename: %s\n", (*parameters).convergenceCriterion,
 			(*parameters).dampingFactor, (*parameters).graphFilename);
 	}
 
@@ -266,37 +275,88 @@ void generateNormalizedTransitionMatrixFromFile(SparseMatrix *transitionMatrix,
 		exit(EXIT_FAILURE);
 	}
 
-	int pageIndex, count = 0;
-	while (fscanf(graphFile, "%d:", &pageIndex) != EOF) {
-		if (!(pageIndex%51050)) {
-			printf("\t%d\t%d%%\n", pageIndex, ++count);
-		}
+	char buffer[FILE_READ_BUFFER_SIZE];
+	char *readResult;
+	// Skips the first two lines
+	readResult = fgets(buffer, FILE_READ_BUFFER_SIZE, graphFile);
+	readResult = fgets(buffer, FILE_READ_BUFFER_SIZE, graphFile);
+	if (readResult == NULL) {
+		printf("Error while reading from the file. Does the file have the correct format?\n");
+		exit(EXIT_FAILURE);
+	}
 
-		char *restOfLine = malloc(MAX_PAGE_LINKS_TEXT_SIZE);
-		if (!fgets(restOfLine, MAX_PAGE_LINKS_TEXT_SIZE, graphFile)) {
-			exit(EXIT_FAILURE);
-		}
+	// Third line contains the numbers of nodes and edges
+	int numberOfNodes = 0, numberOfEdges;
+
+	readResult = fgets(buffer, FILE_READ_BUFFER_SIZE, graphFile);
+	if (readResult == NULL) {
+		printf("Error while reading from the file. Does the file have the correct format?\n");
+		exit(EXIT_FAILURE);
+	}
 
-		char *token = strtok(restOfLine, " ");
+	// Parses the number of nodes and number of edges
+	{
+		// Splits string to whitespace
+		char *token = strtok(buffer, " ");
+		bool nextIsNodes = false, nextIsEdges = false;
 
 		while (token != NULL) {
-			if (strcmp(token, "\n") == 0) {
-				//token = strtok (NULL, " ");
+			if (strcmp(token, "Nodes:") == 0) {
+				nextIsNodes = true;
+			} else if (nextIsNodes) {
+				numberOfNodes = atoi(token);
+				nextIsNodes = false;
+			} else if (strcmp(token, "Edges:") == 0) {
+				nextIsEdges = true;
+			} else if (nextIsEdges) {
+				numberOfEdges = atoi(token);
 				break;
 			}
 
-			int outLink = atoi(token);
-			if (outLink != -1) {
-				apendElement(transitionMatrix, 1, pageIndex, outLink);
-			}
-			token = strtok (NULL, " ");
+			// Gets next string token
+			token = strtok (NULL, " ,.-");
 		}
 	}
-	printf("\t100%%\n");
-	printf("number of edges = %d\n", transitionMatrix->elements);
 
-	(*parameters).numberOfPages = pageIndex + 1;
+	if ((*parameters).verbose) {
+		printf("The number of pages is: %d\nThe number of edges is: %d\n",
+			numberOfNodes, numberOfEdges);
+	}
+	(*parameters).numberOfPages = numberOfNodes;
+
+	// Skips the fourth line
+	readResult = fgets(buffer, 512, graphFile);
+	if (readResult == NULL) {
+		printf("Error while reading from the file. Does the file have the correct format?\n");
+		exit(EXIT_FAILURE);
+	}
+
+	printf("SIZE OF STRUCT = %lu Bytes\n", sizeof(SparseMatrixElement));
+
+	int fivePercentIncrements = (int) numberOfEdges/20;
+	fivePercentIncrements = fivePercentIncrements != 0 ? fivePercentIncrements : 1;
+
+	for (int i=0; i<numberOfEdges; i++) {
+		if (((*parameters).verbose) && ((i % fivePercentIncrements) == 0)) {
+			int percentage = (i/fivePercentIncrements)*5;
+			printf("%d%% done", percentage);
+			if (percentage%20 == 0) {
+				printf("\n");
+			} else {
+				printf(" •••• ");
+			}
+		}
+
+		int fileFrom = 0, fileTo = 0;
+		if (!fscanf(graphFile, "%d %d", &fileFrom, &fileTo)) {
+			break;
+		}
+
+		apendElement(transitionMatrix, 1, fileFrom, fileTo);
+	}
 
+	// Calculates the outdegree of each page and assigns the uniform probability
+	// of transition to the elements of the corresponding row
 	int currentRow = transitionMatrix->firstElement->rowIndex;
 	SparseMatrixElement *startElement = transitionMatrix->firstElement;
 	while(true) {
@@ -315,9 +375,10 @@ void generateNormalizedTransitionMatrixFromFile(SparseMatrix *transitionMatrix,
 
 		// Assigns the value 1/outdegree to current page's columns
 		currentElement = startElement;
+		double pageUniformProbability = 1. / pageOutdegree;
 		for (int i=0; i<pageOutdegree; ++i) {
 			if (currentElement->rowIndex == currentRow) {
-				currentElement->value = 1. / pageOutdegree;
+				currentElement->value = pageUniformProbability;
 				currentElement = currentElement->nextElement;
 			} else {
 				break;
@@ -341,18 +402,18 @@ void generateNormalizedTransitionMatrixFromFile(SparseMatrix *transitionMatrix,
  * correct (valid) way to use the program.
 */
 void validUsage(char *programName) {
-	printf("%s [-c convergence_criterion] [-m max_iterations] [-a alpha] [-v] [-h] [-o output_filename] <graph_file>\
-		\n-c convergence_criterion\
-		\n\tthe convergence tolerance criterion\
-		\n-m max_iterations\
-		\n\tmaximum number of iterations to perform\
-		\n-a alpha\
-		\n\tthe damping factor\
-		\n-v enable verbal output\
-		\n-h enable history output to file\
-		\n-o output_filename\
-		\n\tfilename and path for the output\
-		\n", programName);
+	printf("%s [-c convergence_criterion] [-m max_iterations] [-a alpha] [-v] [-h] [-o output_filename] <graph_file>" \
+		"\n-c convergence_criterion" \
+		"\n\tthe convergence tolerance criterion" \
+		"\n-m max_iterations" \
+		"\n\tmaximum number of iterations to perform" \
+		"\n-a alpha" \
+		"\n\tthe damping factor" \
+		"\n-v enable verbal output" \
+		"\n-h enable history output to file" \
+		"\n-o output_filename" \
+		"\n\tfilename and path for the output" \
+		"\n", programName);
 	exit(EXIT_FAILURE);
 }
 

serial/serial_gs_pagerank_functions.h

@@ -9,6 +9,13 @@
 
 #include "sparse_matrix.h"
 
+#define ANSI_COLOR_RED     "\x1B[31m"
+#define ANSI_COLOR_GREEN   "\x1B[32m"
+#define ANSI_COLOR_YELLOW  "\x1B[33m"
+#define ANSI_COLOR_BLUE    "\x1B[34m"
+#define ANSI_COLOR_CYAN    "\x1B[36m"
+#define ANSI_COLOR_RESET   "\x1B[0m"
+
 /*
  * Constant strings that store the command line options available.
 */
@@ -79,6 +86,7 @@ void matrixVectorMultiplication(SparseMatrix *transitionMatrix,
 // Function pagerank iteratively calculates the pagerank of each page until
 // either the convergence criterion is met or the maximum number of iterations
 // is reached.
-int pagerank(SparseMatrix *transitionMatrix, double **pagerankVector, Parameters parameters);
+int pagerank(SparseMatrix *transitionMatrix, double **pagerankVector,
+	bool *convergenceStatus, Parameters parameters);
 
 #endif	// SERIAL_GS_PAGERANK_FUNCTIONS_H

serial/sparse_matrix.c

@@ -4,6 +4,7 @@ SparseMatrix createSparseMatrix() {
 	SparseMatrix sparseMatrix;
 	sparseMatrix.elements = 0;
 	sparseMatrix.firstElement = NULL;
+	sparseMatrix.lastElement = NULL;
 	return sparseMatrix;
 }
 
@@ -18,14 +19,13 @@ void apendElement(SparseMatrix *sparseMatrix, double value, int row, int column)
 	if (sparseMatrix->firstElement == NULL) {
 		// Sparse matrix is empty, this is the first element
 		sparseMatrix->firstElement = newElement;
+		sparseMatrix->lastElement = newElement;
 	} else {
 		//Gets last element of the matrix
-		SparseMatrixElement *lastElement = sparseMatrix->firstElement;
-		while (lastElement->nextElement != NULL) {
-			lastElement = lastElement->nextElement;
-		}
+		SparseMatrixElement *lastElement = sparseMatrix->lastElement;
 
 		lastElement->nextElement = newElement;
+		sparseMatrix->lastElement = newElement;
 	}
 
 	sparseMatrix->elements = sparseMatrix->elements + 1;
@@ -39,6 +39,7 @@ bool deleteElement(SparseMatrix *sparseMatrix, int row, int column) {
 		// Matrix has one element. Deletes it.
 		free(sparseMatrix->firstElement);
 		sparseMatrix->firstElement = NULL;
+		sparseMatrix->lastElement = NULL;
 		sparseMatrix->elements = sparseMatrix->elements - 1;
 		return true;
 	}
@@ -58,6 +59,9 @@ bool deleteElement(SparseMatrix *sparseMatrix, int row, int column) {
 		SparseMatrixElement *nextElement = currentElement->nextElement;
 		if (nextElement->rowIndex == row && nextElement->columnIndex == column) {
 			currentElement->nextElement = nextElement->nextElement;
+			if (currentElement->nextElement == NULL) {
+				sparseMatrix->lastElement = currentElement;
+			}
 			free(nextElement);
 			sparseMatrix->elements = sparseMatrix->elements - 1;
 			return true;

serial/sparse_matrix.h

@@ -15,6 +15,7 @@ typedef struct sparseMatrixElement {
 typedef struct sparseMatrix {
 	int elements;
 	SparseMatrixElement *firstElement;
+	SparseMatrixElement *lastElement;
 } SparseMatrix;
 
 SparseMatrix createSparseMatrix();