From aa8c41f346d2ff75745f81e77b399e9882b57226 Mon Sep 17 00:00:00 2001
From: yikth <netyth@gmail.com>
Date: Mon, 31 Aug 2020 18:10:26 +0800
Subject: [PATCH] dynamically create 2D array to store csv data

---
 Day1Exercise/Q2/dataset.csv    |  4 +++-
 Day1Exercise/Q2/scatterPlot.js | 37 +++++++++++++++++++---------------
 2 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/Day1Exercise/Q2/dataset.csv b/Day1Exercise/Q2/dataset.csv
index 55cfc52..d999ac4 100644
--- a/Day1Exercise/Q2/dataset.csv
+++ b/Day1Exercise/Q2/dataset.csv
@@ -3,4 +3,6 @@ x,y
 20,20
 5,20
 7,4
-22,6
\ No newline at end of file
+22,6
+11,33
+10,13
\ No newline at end of file
diff --git a/Day1Exercise/Q2/scatterPlot.js b/Day1Exercise/Q2/scatterPlot.js
index 090df65..f62e8b9 100644
--- a/Day1Exercise/Q2/scatterPlot.js
+++ b/Day1Exercise/Q2/scatterPlot.js
@@ -1,30 +1,35 @@
 function myScatterPlot() {
     var dataset = [[10, 15], [20, 20], [5, 20], [7, 4], [22, 6]];
     console.log("entering...");
-    
+
     //debugger;
+    // for D3.js v5 and above, d3.csv() use promise design pattern
     const myPromise = d3.csv("./dataset.csv");
-    
-    myPromise.then((data)  => {
 
-        //debugger;
-        console.log("callback...")
+    myPromise.then((data) => {
+            //debugger;
+            console.log("callback...")
 
-        var i=0;
-        data.forEach(d => {
-            d.x = +d.x;
-            d.y = +d.y;
+            var i = 0;
+            var csvDataset = new Array(data.length);
+            for (var ii = 0; ii < csvDataset.length; ii++) { 
+                csvDataset[ii] = new Array(2); 
+            } 
             //
-            dataset[i][0] = d.x;
-            dataset[i][1] = d.y;
-            i++;
-        });
+            data.forEach(d => {
+                d.x = +d.x;
+                d.y = +d.y;
+                //
+                csvDataset[i][0] = d.x;
+                csvDataset[i][1] = d.y;
+                i++;
+            });
 
-        // plot to view
-        plot(dataset);
+            // plot to view
+            plot(csvDataset);
         })
         .catch(error => {
-            alert("File Missing!!!")
+            alert(`dataset error : ${error.message}`)
         });
 
 }