chore: Refactored and added comments

lib/comparisonView.js

@@ -1,7 +1,7 @@
 /* Imports */
 import Head from 'next/head'
 import React, { useState } from "react";
-import { DrawGraph, removeOldSvg } from './labeledgraph';
+import { DrawGraph, removeOldSvg } from './labeledGraph';
 import { SubmitSliderButton } from "./slider";
 import { DisplayElement } from './displayElement'
 import { DisplayAsMarkdown } from './displayAsMarkdown'

lib/findPaths.js

@@ -1,49 +1,55 @@
 /* Imports*/
-import React, { useState, useEffect } from 'react';
-import { toLocale, truncateValueForDisplay, numToAlphabeticalString, formatLargeOrSmall } from "../lib/utils.js"
+import React from 'react';
+import { numToAlphabeticalString, formatLargeOrSmall, avg } from "../lib/utils.js"
 
-/* Utilities */
-let avg = arr => arr.reduce((a, b) => (a + b), 0) / arr.length
+/* Functions */
 
-/* Main function */
+const pathPlusLink = (pathSoFar, link) => {
+    return [...pathSoFar, link]
+    // previously: pathSoFar.concat(link).flat()
+    // Note that concat is not destructive
+    // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/concat
+}
 
-async function findPathsInner({
-    sourceElementId, sourceElementPosition,
-    targetElementId, targetElementPosition,
-    links, nodes,
-    maxLengthOfPath, pathSoFar
+async function findPathsWithoutPrunning({
+    sourceElementId, targetElementId,
+    maxLengthOfPath, pathSoFar,
+    links, nodes
 }) {
+    // This is an un-used function which might make findPaths more understandable
+    // It uses the same recursive functionality 
+    // but has no path prunning
     let paths = []
-    let minPos = Math.min(sourceElementPosition, targetElementPosition)
-    let maxPos = Math.max(sourceElementPosition, targetElementPosition)
-    let linksInner = links.filter(link =>
-        (minPos <= link.sourceElementPosition && link.sourceElementPosition <= maxPos) &&
-        (minPos <= link.targetElementPosition && link.targetElementPosition <= maxPos)
-    )
-    let linksNow = linksInner.filter(link => (link.source == sourceElementId || link.target == sourceElementId))
+
+    /* Path traversing */
     if (maxLengthOfPath > 0) {
-        for (let link of linksNow) {
+        for (let link of links) { // vs let link of linksNow in findPaths
             if (
                 ((link.source == sourceElementId) && (link.target == targetElementId)) ||
                 ((link.source == targetElementId) && (link.target == sourceElementId))
-            ) {
-                paths.push(pathSoFar.concat(link).flat())
+            ) { // direct Path
+                let newPath = pathPlusLink(pathSoFar, link)
+                paths.push(newPath)
             } else if ((link.source == sourceElementId)) {
-                let newPaths = await findPathsInner({
-                    sourceElementId: link.target, sourceElementPosition: link.sourceElementPosition,
-                    targetElementId, targetElementPosition,
-                    pathSoFar: pathSoFar.concat(link).flat(),
-                    links: linksInner, nodes, maxLengthOfPath: (maxLengthOfPath - 1)
+                let newPaths = await findPaths({
+                    pathSoFar: pathPlusLink(pathSoFar, link),
+                    maxLengthOfPath: (maxLengthOfPath - 1),
+                    sourceElementId: link.target,
+                    targetElementId,
+                    links: links, // vs let link of linksInner in findPaths
+                    nodes
                 })
-                if (newPaths.length != 0) {
+                if (newPaths.length != 0) { 
                     paths.push(...newPaths)
                 }
             } else if ((link.target == sourceElementId)) {
-                let newPaths = await findPathsInner({
-                    sourceElementId: link.source, sourceElementPosition: link.sourceElementPosition,
-                    targetElementId, targetElementPosition,
-                    pathSoFar: pathSoFar.concat(link).flat(),
-                    links: linksInner, nodes, maxLengthOfPath: (maxLengthOfPath - 1)
+                let newPaths = await findPaths({
+                    pathSoFar: pathPlusLink(pathSoFar, link),
+                    maxLengthOfPath: (maxLengthOfPath - 1),
+                    sourceElementId: link.source,
+                    targetElementId,
+                    links: links, // vs let link of linksInner in findPaths
+                    nodes
                 })
                 if (newPaths.length != 0) {
                     paths.push(...newPaths)
@@ -54,40 +60,93 @@ async function findPathsInner({
 
     return paths
 }
-/*  
-function findPaths({
+
+async function findPaths({
     sourceElementId, sourceElementPosition,
     targetElementId, targetElementPosition,
-    nodes, links, direction
+    maxLengthOfPath, pathSoFar,
+    links, nodes
 }) {
-    let positionSourceElement = nodes.map((element, i) => (element.id)).indexOf(sourceElementId)
-    let positionTargetElement = nodes.map((element, i) => (element.id)).indexOf(targetElementId)
-    let maxLengthOfPath = Math.abs(positionSourceElement - positionTargetElement)
-    return findPathsInner({
-        sourceElementId, sourceElementPosition,
-        targetElementId, targetElementPosition,
-        links, nodes, direction,
-        maxLengthOfPath, pathSoFar: []
-    })
+    // This is the key path finding function
+    // It finds the path from one element to another, recursively
+    // It used to be very computationally expensive until I added
+    // the path prunning step: Instead of traversing all links,
+    // traverse only those which are between the origin and target links
+    // this requires us to have a notion of "between"
+
+    let paths = []
+
+    /* Path prunning*/
+    let minPos = Math.min(sourceElementPosition, targetElementPosition)
+    let maxPos = Math.max(sourceElementPosition, targetElementPosition)
+    let linksInner = links.filter(link =>
+        (minPos <= link.sourceElementPosition && link.sourceElementPosition <= maxPos) &&
+        (minPos <= link.targetElementPosition && link.targetElementPosition <= maxPos)
+    )
+    let linksNow = linksInner.filter(link => (link.source == sourceElementId || link.target == sourceElementId))
+
+    /* Path traversing */
+    if (maxLengthOfPath > 0) {
+        for (let link of linksNow) {
+            if (
+                ((link.source == sourceElementId) && (link.target == targetElementId)) ||
+                ((link.source == targetElementId) && (link.target == sourceElementId))
+            ) { // direct Path
+                let newPath = pathPlusLink(pathSoFar, link)
+                paths.push(newPath)
+            } else if ((link.source == sourceElementId)) {
+                let newPaths = await findPaths({
+                    pathSoFar: pathPlusLink(pathSoFar, link),
+                    maxLengthOfPath: (maxLengthOfPath - 1),
+                    sourceElementPosition: link.sourceElementPosition,
+                    sourceElementId: link.target,
+                    targetElementId, targetElementPosition,
+                    links: linksInner,
+                    nodes
+                })
+                if (newPaths.length != 0) {
+                    paths.push(...newPaths)
+                }
+            } else if ((link.target == sourceElementId)) {
+                let newPaths = await findPaths({
+                    pathSoFar: pathPlusLink(pathSoFar, link),
+                    maxLengthOfPath: (maxLengthOfPath - 1),
+                    sourceElementPosition: link.sourceElementPosition,
+                    sourceElementId: link.source,
+                    targetElementPosition,
+                    targetElementId,
+                    links: linksInner,
+                    nodes
+                })
+                if (newPaths.length != 0) {
+                    paths.push(...newPaths)
+                }
+            }
+        }
+    }
+
+    return paths
 }
-*/
 
 async function findDistance({
     sourceElementId, sourceElementPosition,
     targetElementId, targetElementPosition,
-    nodes, links, direction
+    nodes, links
 }) {
+    // This function gets all possible paths using findPaths
+    // then orders them correctly in the for loop 
+    // (by flipping the distance to 1/distance when necessary)
+    // and then gets the array of weights for the different paths.
+    console.log(`findDistance@findPaths.js from ${sourceElementPosition} to ${targetElementPosition}`)
+
     let maxLengthOfPath = Math.abs(sourceElementPosition - targetElementPosition)
-    let paths = await findPathsInner({
+    let paths = await findPaths({
         sourceElementId, sourceElementPosition,
         targetElementId, targetElementPosition,
-        links, nodes, direction,
+        links, nodes,
         maxLengthOfPath, pathSoFar: []
     });
-    console.log(`findDistance from ${sourceElementPosition} to ${targetElementPosition}`)
-    console.log(targetElementId)
-    console.log(direction)
-    console.log(paths)
+
     let weights = []
     for (let path of paths) {
         let currentSource = sourceElementId
@@ -106,25 +165,26 @@ async function findDistance({
         }
         weights.push(weight)
     }
-    //let sum = JSON.stringify(weights)//weights.length > 0 ? weights.reduce((a,b) => (a+b)) / weights.length : "Not found"
-    //return sum
     return weights
-    //return weights.map(weight => Math.round(weight*100)/100)
 }
 
 async function findDistancesForAllElements({ nodes, links }) {
+    // Simple wrapper function around findDistance
+    // Needs to find the reference point first
+    console.log("findDistancesForAllElements@findPaths.js")
+    /* Get or build reference element */
     let referenceElements = nodes.filter(x => x.isReferenceValue)
     let midpoint = Math.round(nodes.length / 2)
     let referenceElement = referenceElements.length > 0 ? referenceElements[0] : nodes[midpoint]
-    // console.log(nodes)
     console.log(`referenceElement.position: ${referenceElement.position}`)
+
+    /* Get distances. */
     let distances = nodes.map(node => {
         if (node.isReferenceValue || (node.id == referenceElement.id)) {
             return [1]
         } else {
             console.log("node")
             console.log(node)
-            let isUpwardsDirection = referenceElement.position < node.position
             let distance = findDistance({
                 sourceElementId: referenceElement.id,
                 sourceElementPosition: referenceElement.position,
@@ -132,7 +192,6 @@ async function findDistancesForAllElements({ nodes, links }) {
                 targetElementPosition: node.position,
                 nodes: nodes,
                 links: links,
-                direction: isUpwardsDirection ? "upwards" : "downwards"
             })
             return distance
         }
@@ -141,23 +200,11 @@ async function findDistancesForAllElements({ nodes, links }) {
     return distances
 }
 
-function abridgeArrayAndDisplay(array) {
-    let newArray
-    let formatForDisplay
-    if (array.length > 10) {
-        newArray = array.slice(0, 9)
-        formatForDisplay = newArray.map(d => formatLargeOrSmall(d))
-        formatForDisplay[9] = "..."
-    } else {
-        newArray = array
-        formatForDisplay = newArray.map(d => formatLargeOrSmall(d))
-    }
-    let result = JSON.stringify(formatForDisplay, null, 2).replaceAll(`"`, "")
-    return result
-}
-
 export async function buildRows({ isListOrdered, orderedList, listOfElements, links, rows, setTableRows }) {
-    // Not used yet.
+    console.log("buildRows@findPaths.js")
+    // This function is used in pages/comparisonView.js to create the rows that will be displayed.
+    // it is in there because it needs to be deployed after isListOrdered becomes true,
+    // and using an useEffect inside CreateTable was too messy.
     if (isListOrdered && !(orderedList.length < listOfElements.length) && rows.length == 0) {
         let nodes = []
         let positionDictionary = ({})
@@ -165,8 +212,6 @@ export async function buildRows({ isListOrdered, orderedList, listOfElements, li
             nodes.push({ ...listOfElements[id], position: pos })
             positionDictionary[id] = pos
         })
-        // let nodes = orderedList.map((id, pos) => ({ ...listOfElements[id], position: pos }))
-        /* Pre-process links to talk in terms of distances */
         links = links.map(link => ({
             ...link,
             sourceElementPosition: positionDictionary[link.source],
@@ -180,161 +225,63 @@ export async function buildRows({ isListOrdered, orderedList, listOfElements, li
             name: element.name,
             distances: distances[i]
         }))
-        console.log("rows@CreateTableWithDistances")
         console.log(rows)
         setTableRows(rows)
-    } else {
-        // rows = []
-        // Do nothing
     }
-    // return rows
 }
-export function CreateTableWithDistancesWithUseEffect({ isListOrdered, orderedList, listOfElements, links, tableRows, setTableRows }) {
-    
-    useEffect(async () => {
-        await buildRows({ isListOrdered, orderedList, listOfElements, links, rows: tableRows, setTableRows })
-        /*
-        // https://stackoverflow.com/questions/57847626/using-async-await-inside-a-react-functional-component
-        // https://stackoverflow.com/questions/54936559/using-async-await-in-react-component
-        // https://reactjs.org/docs/hooks-effect.html#tip-optimizing-performance-by-skipping-effects
-        if (isListOrdered && ! (orderedList.length < listOfElements.length) && rows.length == 0) {
-            let nodes = []
-            let positionDictionary=({})
-            orderedList.forEach((id, pos) => {
-                nodes.push({ ...listOfElements[id], position: pos })
-                positionDictionary[id] = pos
-            })
-            // let nodes = orderedList.map((id, pos) => ({ ...listOfElements[id], position: pos }))
-            // Pre-process links to talk in terms of distances
-            links = links.map(link => ({...link, 
-                sourceElementPosition: positionDictionary[link.source], 
-                targetElementPosition: positionDictionary[link.target]
-            }))
-    
-            let distances = await findDistancesForAllElements({ nodes, links })
-            setRows(nodes.map((element, i) => ({ 
-                id: numToAlphabeticalString(element.position), 
-                position: element.position, 
-                name: element.name, 
-                distances: distances[i] 
-            })))
-            console.log("rows@CreateTableWithDistances")
-            console.log(rows)
+
+export function CreateTable({ tableRows }) {
+    /* This function receives a list of rows, and displays them nicely. */
+    function abridgeArrayAndDisplay(array) {
+        let newArray
+        let formatForDisplay
+        if (array.length > 10) {
+            newArray = array.slice(0, 9)
+            formatForDisplay = newArray.map(d => formatLargeOrSmall(d))
+            formatForDisplay[9] = "..."
+        } else {
+            newArray = array
+            formatForDisplay = newArray.map(d => formatLargeOrSmall(d))
         }
-        */
-    }); // this useEffect should ideally only work when isListOrdered changes, but I haven't bothered to program that.
-    
-
-    return (
-        <div>
-            <table className="">
-                <thead>
-                    <tr >
-                        <th >Id</th>
-                        <th>&nbsp;&nbsp;&nbsp;</th>
-                        <th >Position</th>
-                        <th>&nbsp;&nbsp;&nbsp;</th>
-                        <th >Element</th>
-                        <th> &nbsp;&nbsp;&nbsp;</th>
-                        <th >Possible relative values</th>
-                        <th> &nbsp;&nbsp;&nbsp;</th>
-                        <th >Average relative value</th>
-                    </tr>
-                </thead>
-                <tbody>
-                    {tableRows.map(row => <tr key={row.id}>
-                        <td className="" >{row.id}</td>
-                        <td>&nbsp;&nbsp;&nbsp;</td>
-                        <td className="" >{row.position}</td>
-                        <td>&nbsp;&nbsp;&nbsp;</td>
-                        <td className="">{row.name}</td>
-                        <td>&nbsp;&nbsp;&nbsp;</td>
-                        <td className="">{abridgeArrayAndDisplay(row.distances)}</td>
-                        <td>&nbsp;&nbsp;&nbsp;</td>
-                        <td className="">{formatLargeOrSmall(avg(row.distances))}</td>
-                    </tr>
-                    )}
-                </tbody>
-            </table>
-        </div>
-    )
-
-}    
-
-export function CreateTableWithDistances({ tableRows }) {
-    return (
-        <div>
-            <table className="">
-                <thead>
-                    <tr >
-                        <th >Id</th>
-                        <th>&nbsp;&nbsp;&nbsp;</th>
-                        <th >Position</th>
-                        <th>&nbsp;&nbsp;&nbsp;</th>
-                        <th >Element</th>
-                        <th> &nbsp;&nbsp;&nbsp;</th>
-                        <th >Possible relative values</th>
-                        <th> &nbsp;&nbsp;&nbsp;</th>
-                        <th >Average relative value</th>
-                    </tr>
-                </thead>
-                <tbody>
-                    {tableRows.map(row => <tr key={row.id}>
-                        <td className="" >{row.id}</td>
-                        <td>&nbsp;&nbsp;&nbsp;</td>
-                        <td className="" >{row.position}</td>
-                        <td>&nbsp;&nbsp;&nbsp;</td>
-                        <td className="">{row.name}</td>
-                        <td>&nbsp;&nbsp;&nbsp;</td>
-                        <td className="">{abridgeArrayAndDisplay(row.distances)}</td>
-                        <td>&nbsp;&nbsp;&nbsp;</td>
-                        <td className="">{formatLargeOrSmall(avg(row.distances))}</td>
-                    </tr>
-                    )}
-                </tbody>
-            </table>
-        </div>
-    )
-
-}
-
-function CreateTableWithoutDistances({ isListOrdered, orderedList, listOfElements, links }) {
-    if (!isListOrdered || orderedList.length < listOfElements.length) {
-        return (<div>{""}</div>)
-    } else {
-        let nodes = orderedList.map(i => listOfElements[i])
-        let rows = nodes.map((element, i) => ({ id: numToAlphabeticalString(element.id), name: element.name }))
-        console.log("rows@CreateTableWithoutDistances")
-        console.log(rows)
-        return (
-            <div>
-                <table className="">
-                    <thead >
-                        <tr >
-                            <th >Id</th>
-                            <th>&nbsp;&nbsp;&nbsp;</th>
-                            <th >Element</th>
-                            <th> &nbsp;&nbsp;&nbsp;</th>
-                        </tr>
-                    </thead>
-                    <tbody>
-                        {rows.map(row => <tr key={row.id}>
-                            <td className="" >{row.id}</td>
-                            <td>&nbsp;&nbsp;&nbsp;</td>
-                            <td className="">{row.name}</td>
-                        </tr>
-                        )}
-                        { }
-                    </tbody>
-                </table>
-            </div>
-        )
+        let result = JSON.stringify(formatForDisplay, null, 2).replaceAll(`"`, "")
+        return result
     }
+    return (
+        <div>
+            <table className="">
+                <thead>
+                    <tr >
+                        <th >Id</th>
+                        <th>&nbsp;&nbsp;&nbsp;</th>
+                        <th >Position</th>
+                        <th>&nbsp;&nbsp;&nbsp;</th>
+                        <th >Element</th>
+                        <th> &nbsp;&nbsp;&nbsp;</th>
+                        <th >Possible relative values</th>
+                        <th> &nbsp;&nbsp;&nbsp;</th>
+                        <th >Average relative value</th>
+                    </tr>
+                </thead>
+                <tbody>
+                    {tableRows.map(row => <tr key={row.id}>
+                        <td className="" >{row.id}</td>
+                        <td>&nbsp;&nbsp;&nbsp;</td>
+                        <td className="" >{row.position}</td>
+                        <td>&nbsp;&nbsp;&nbsp;</td>
+                        <td className="">{row.name}</td>
+                        <td>&nbsp;&nbsp;&nbsp;</td>
+                        <td className="">{abridgeArrayAndDisplay(row.distances)}</td>
+                        <td>&nbsp;&nbsp;&nbsp;</td>
+                        <td className="">{formatLargeOrSmall(avg(row.distances))}</td>
+                    </tr>
+                    )}
+                </tbody>
+            </table>
+        </div>
+    )
 
 }
 
-export const CreateTable = CreateTableWithDistances // CreateTableWithoutDistances;
-
 /* Testing */
 //import fs from 'fs';
 //import path from 'path';
@@ -343,7 +290,7 @@ const directory = path.join(process.cwd(),"pages")
 let links = JSON.parse(fs.readFileSync(path.join(directory, 'distancesExample.json'), 'utf8'));
 let nodes = JSON.parse(fs.readFileSync(path.join(directory, 'listOfPosts.json'), 'utf8'));
 
-let paths = findPathsInner({sourceElementId:2, targetElementId:0, pathSoFar: [], links, nodes, maxLengthOfPath: 2})
+let paths = findPaths({sourceElementId:2, targetElementId:0, pathSoFar: [], links, nodes, maxLengthOfPath: 2})
 console.log(JSON.stringify(paths, null, 2))
 */
 /*

lib/labeledGraph.js

@@ -1,6 +1,6 @@
 import React, { useState, useEffect } from "react";
 import * as d3 from 'd3';
-import { toLocale, truncateValueForDisplay, numToAlphabeticalString, formatLargeOrSmall } from "../lib/utils.js"
+import { toLocale, truncateValueForDisplay, numToAlphabeticalString, formatLargeOrSmall } from "./utils.js"
 
 let getlength = (number) => number.toString().length;
 

lib/utils.js

@@ -67,4 +67,6 @@ export function expectedNumMergeSortSteps(n) {
     } else {
         return Math.ceil((n ** 2) / (n + 2)) + expectedNumMergeSortSteps(Math.ceil(n / 2))
     }
-}
+}
+
+export const avg = arr => arr.reduce((a, b) => (a + b), 0) / arr.length