From 3a35e2e3c5df3804b4bb900309021556a7b1d5af Mon Sep 17 00:00:00 2001 From: Emile Date: Sun, 10 Feb 2019 22:07:06 +0100 Subject: updated the function comments --- db_actions.go | 149 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 141 insertions(+), 8 deletions(-) (limited to 'db_actions.go') diff --git a/db_actions.go b/db_actions.go index 3d4054d..4e87850 100644 --- a/db_actions.go +++ b/db_actions.go @@ -31,14 +31,14 @@ import ( ) const ( - DB_USER = "postgres" - DB_NAME = "postgres" - DB_SSLMODE = "disable" + DBUSER = "postgres" + DBNAME = "postgres" + DBSSLMODE = "disable" ) -//connectToDB returns a pointer to an sql database writing to the database +// connectToDB returns a pointer to an sql database writing to the database func connectToDB() *sql.DB { - connStr := fmt.Sprintf("user=%s dbname=%s sslmode=%s", DB_USER, DB_NAME, DB_SSLMODE) + connStr := fmt.Sprintf("user=%s dbname=%s sslmode=%s", DBUSER, DBNAME, DBSSLMODE) db := dbConnect(connStr) return db } @@ -54,7 +54,7 @@ func dbConnect(connStr string) *sql.DB { return db } -//func newTree(db *sql.DB, width float64) { +// newTree creates a new tree with the given width func newTree(width float64) { // get the current max root id query := fmt.Sprintf("SELECT COALESCE(max(root_id), 0) FROM nodes") @@ -74,6 +74,7 @@ func newTree(width float64) { } } +// insertStar inserts the given star into the stars table and the nodes table tree func insertStar(star structs.Star2D, index int64) { start := time.Now() // insert the star into the stars table @@ -115,6 +116,7 @@ func insertIntoStars(star structs.Star2D) int64 { return starID } +// insert into tree inserts the given star into the tree starting at the node with the given node id func insertIntoTree(starID int64, nodeID int64) { //starRaw := getStar(starID) //nodeCenter := getBoxCenter(nodeID) @@ -200,8 +202,7 @@ func insertIntoTree(starID int64, nodeID int64) { } } -// containsStar returns true if the node with the given id contains a star -// and returns false if not. +// containsStar returns true if the node with the given id contains a star and returns false if not. func containsStar(id int64) bool { var starID int64 @@ -248,6 +249,7 @@ func directInsert(starID int64, nodeID int64) { } } +// subdivide subdivides the given node creating four child nodes func subdivide(nodeID int64) { boxWidth := getBoxWidth(nodeID) boxCenter := getBoxCenter(nodeID) @@ -331,6 +333,7 @@ func newNode(x float64, y float64, width float64, depth int64) int64 { return nodeID } +// getStarID returns the id of the star inside of the node with the given ID func getStarID(nodeID int64) int64 { // get the star id from the node var starID int64 @@ -439,6 +442,7 @@ func getQuadrantNodeID(parentNodeID int64, quadrant int64) int64 { return -1 } +// getStar returns the star with the given ID from the stars table func getStar(starID int64) structs.Star2D { var x, y, vx, vy, m float64 @@ -464,6 +468,7 @@ func getStar(starID int64) structs.Star2D { return star } +// getStarMass returns the mass if the star with the given ID func getStarMass(starID int64) float64 { var mass float64 @@ -477,6 +482,21 @@ func getStarMass(starID int64) float64 { return mass } +// getNodeTotalMass returns the total mass of the node with the given ID and its children +func getNodeTotalMass(nodeID int64) float64 { + var mass float64 + + // get the star from the stars table + query := fmt.Sprintf("SELECT total_mass FROM nodes WHERE node_id=%d", nodeID) + err := db.QueryRow(query).Scan(&mass) + if err != nil { + log.Fatalf("[ E ] getStarMass query: %v \n\t\t\tquery: %s\n", err, query) + } + + return mass +} + +// removeStarFromNode removes the star from the node with the given ID func removeStarFromNode(nodeID int64) { // build the query query := fmt.Sprintf("UPDATE nodes SET star_id=0 WHERE node_id=%d", nodeID) @@ -489,6 +509,7 @@ func removeStarFromNode(nodeID int64) { } } +// getListOfStarsGo returns the list of stars in go struct format func getListOfStarsGo() []structs.Star2D { // build the query query := fmt.Sprintf("SELECT * FROM stars") @@ -530,6 +551,7 @@ func getListOfStarsGo() []structs.Star2D { return starList } +// getListOfStarsCsv returns an array of strings containing the coordinates of all the stars in the stars table func getListOfStarsCsv() []string { // build the query query := fmt.Sprintf("SELECT * FROM stars") @@ -560,6 +582,7 @@ func getListOfStarsCsv() []string { return starList } +// insertList inserts all the stars in the given .csv into the stars and nodes table func insertList(filename string) { // open the file content, readErr := ioutil.ReadFile(filename) @@ -667,3 +690,113 @@ func updateTotalMassNode(nodeID int64) float64 { return totalmass } + +// updateCenterOfMass recursively updates the center of mass of all the nodes starting at the node with the given +// root index +func updateCenterOfMass(index int64) { + rootNodeID := getRootNodeID(index) + log.Printf("RootID: %d", rootNodeID) + updateCenterOfMassNode(rootNodeID) +} + +// updateCenterOfMassNode updates the center of mass of the node with the given nodeID recursively +func updateCenterOfMassNode(nodeID int64) structs.Vec2 { + var nominatorX float64 + var deNominatorX float64 + var nominatorY float64 + var deNominatorY float64 + + var centerOfMassX float64 + var centerOfMassY float64 + var centerOfMass structs.Vec2 + + // get the subnode ids + var subnode [4]int64 + + query := fmt.Sprintf("SELECT subnode[1], subnode[2], subnode[3], subnode[4] FROM nodes WHERE node_id=%d", nodeID) + err := db.QueryRow(query).Scan(&subnode[0], &subnode[1], &subnode[2], &subnode[3]) + if err != nil { + log.Fatalf("[ E ] updateCenterOfMassNode query: %v\n\t\t\t query: %s\n", err, query) + } + + // iterate over all subnodes updating their total masses + for _, subnodeID := range subnode { + fmt.Println("----------------------------") + fmt.Printf("SubdnodeID: %d\n", subnodeID) + if subnodeID != 0 { + nominatorX += updateCenterOfMassNode(subnodeID).X * getNodeTotalMass(subnodeID) + deNominatorX += getNodeTotalMass(subnodeID) + nominatorY += updateCenterOfMassNode(subnodeID).Y * getNodeTotalMass(subnodeID) + deNominatorY += getNodeTotalMass(subnodeID) + } else { + log.Printf("Getting the starID using the nodeID %d", nodeID) + starID := getStarID(nodeID) + if starID != 0 { + // as the cell contains only a single star, the center of mass is the position of that single star + centerOfMass.X = getStar(starID).C.X + centerOfMass.Y = getStar(starID).C.Y + break + } + } + fmt.Println("----------------------------") + } + + // if the center of mass has not been set yet, set it + if centerOfMass == (structs.Vec2{0, 0}) { + if deNominatorX != 0 || deNominatorY != 0 { + centerOfMassX = nominatorX / deNominatorX + centerOfMassY = nominatorY / deNominatorY + } + centerOfMass = structs.Vec2{centerOfMassX, centerOfMassY} + } + + query = fmt.Sprintf("UPDATE nodes SET center_of_mass='{%f, %f}' WHERE node_id=%d", centerOfMassX, centerOfMassY, nodeID) + _, err = db.Query(query) + if err != nil { + log.Fatalf("[ E ] insert center_of_mass query: %v\n\t\t\t query: %s\n", err, query) + } + + fmt.Printf("nodeID: %d \t totalMass: %v\n", nodeID, centerOfMass) + + return centerOfMass +} + +// genForestTree generates a forest representation of the tree with the given index +func genForestTree(index int64) string { + rootNodeID := getRootNodeID(index) + return genForestTreeNode(rootNodeID) +} + +// genForestTreeNodes returns a sub-representation of a given node in forest format +func genForestTreeNode(nodeID int64) string { + var returnString string + + // get the subnode ids + var subnode [4]int64 + + query := fmt.Sprintf("SELECT subnode[1], subnode[2], subnode[3], subnode[4] FROM nodes WHERE node_id=%d", nodeID) + err := db.QueryRow(query).Scan(&subnode[0], &subnode[1], &subnode[2], &subnode[3]) + if err != nil { + log.Fatalf("[ E ] updateTotalMassNode query: %v\n\t\t\t query: %s\n", err, query) + } + + returnString += "[" + + // iterate over all subnodes updating their total masses + for _, subnodeID := range subnode { + if subnodeID != 0 { + returnString += genForestTreeNode(subnodeID) + } else { + + // get the starID for getting the star mass + starID := getStarID(nodeID) + returnString += fmt.Sprintf("[%d]", starID) + // break, this stops a star from being counted multiple (4) times + break + } + } + + returnString += "]" + + return returnString +} -- cgit 1.4.1