course wesbos#4 finished

Author: Jin Xu

04 - Array Cardio Day 1/index-START.html

@@ -31,29 +31,62 @@
 
     // Array.prototype.filter()
     // 1. Filter the list of inventors for those who were born in the 1500's
-
+    let result_1 = inventors.filter((person) => person.year >= 1500 && person.year < 1600)
+    console.table(result_1);
+    
     // Array.prototype.map()
     // 2. Give us an array of the inventors' first and last names
+    let result_2 = [];
+    inventors.map(person => {result_2.push(person.first + ' ' + person.last)})
+    console.log(result_2);
 
     // Array.prototype.sort()
     // 3. Sort the inventors by birthdate, oldest to youngest
+    inventors.sort((a, b) => (- a.year + b.year))
+    console.table(inventors);
+    
 
     // Array.prototype.reduce()
     // 4. How many years did all the inventors live?
+    // let total = 0;
+    // inventors.reduce((prePerson, curPerson, curIdx, src) => {
+    //   total += (curPerson.passed - curPerson.year)
+    // }, 0)
+    // console.log(total);
+    const totalYears = inventors.reduce((total, inventor) => (total + (inventor.passed - inventor.year)), 0);
+
+    console.log(totalYears);
 
     // 5. Sort the inventors by years lived
+    inventors.sort((a, b) => (-(a.passed - a.year) + (b.passed - b.year)))
+    console.table(inventors);
 
     // 6. create a list of Boulevards in Paris that contain 'de' anywhere in the name
     // https://en.wikipedia.org/wiki/Category:Boulevards_in_Paris
 
+    /* run the code in console of the wiki page*/
+    // var result_6 = [...document.querySelectorAll('.mw-category a')].map(function(i){return i.innerHTML});
+    // result_6.filter((n) => n.indexOf('de')>=0);
 
     // 7. sort Exercise
     // Sort the people alphabetically by last name
+    people.sort((a,b) => (a.split(',')[0].trim() > b.split(',')[0].trim() ? 1 : -1));
+    console.log(people)
 
     // 8. Reduce Exercise
     // Sum up the instances of each of these
     const data = ['car', 'car', 'truck', 'truck', 'bike', 'walk', 'car', 'van', 'bike', 'walk', 'car', 'van', 'car', 'truck' ];
-
+    var result_8 = data.reduce((obj, item) => {
+      if(obj.hasOwnProperty(item)) {
+        obj[item] ++;
+      }
+      else {
+        obj[item] = 0;
+      }
+      return obj;
+    }, {});
+    console.log(result_8);
+    
   </script>
 </body>
 </html>

readme.md

@@ -7,7 +7,7 @@
 1. [x]  ~~JavaScript Drum Kit~~
 2. [x] ~~JS + CSS Clock~~
 3. [x] ~~CSS Variables~~
-4. [ ] Array Cardio, Day 1
+4. [x] ~~Array Cardio, Day 1~~
 5. [ ] Flex Panel Gallery
 6. [ ] Type Ahead
 7. [ ] Array Cardio, Day 2