diff --git a/01_Day/01_day_starter/helloworld.js b/01_Day_Introduction/01_day_starter/helloworld.js similarity index 100% rename from 01_Day/01_day_starter/helloworld.js rename to 01_Day_Introduction/01_day_starter/helloworld.js diff --git a/01_Day/01_day_starter/index.html b/01_Day_Introduction/01_day_starter/index.html similarity index 100% rename from 01_Day/01_day_starter/index.html rename to 01_Day_Introduction/01_day_starter/index.html diff --git a/01_Day/01_day_starter/introduction.js b/01_Day_Introduction/01_day_starter/introduction.js similarity index 100% rename from 01_Day/01_day_starter/introduction.js rename to 01_Day_Introduction/01_day_starter/introduction.js diff --git a/01_Day/01_day_starter/main.js b/01_Day_Introduction/01_day_starter/main.js similarity index 100% rename from 01_Day/01_day_starter/main.js rename to 01_Day_Introduction/01_day_starter/main.js diff --git a/01_Day/01_day_starter/varaible.js b/01_Day_Introduction/01_day_starter/varaible.js similarity index 100% rename from 01_Day/01_day_starter/varaible.js rename to 01_Day_Introduction/01_day_starter/varaible.js diff --git a/01_Day/variable.js b/01_Day_Introduction/variable.js similarity index 100% rename from 01_Day/variable.js rename to 01_Day_Introduction/variable.js diff --git a/02_Day/02_day_data_types.md b/02_Day_Data_types/02_day_data_types.md similarity index 98% rename from 02_Day/02_day_data_types.md rename to 02_Day_Data_types/02_day_data_types.md index 5f1180c8c..198ae2b26 100644 --- a/02_Day/02_day_data_types.md +++ b/02_Day_Data_types/02_day_data_types.md @@ -1,5 +1,5 @@

30 Days Of JavaScript

30 Days Of JavaScript: Data Types

@@ -14,7 +14,7 @@

- _{Author:
- Asabeneh Yetayeh

- January, 2020
-} +_{Author:
+Asabeneh Yetayeh

+ January, 2020
+} +

-[<< Day 8](https://github.com/Asabeneh/30DaysOfJavaScript/blob/master/08_Day/08_day_objects.md) | [Day 10 >>](https://github.com/Asabeneh/30DaysOfJavaScript/blob/master/10_Day/10_day_Set_and_Map.md) +[<< Day 8](../08_Day_Objects/08_day_objects.md) | [Day 10 >>](../10_Day_Sets_and_Maps/10_day_Sets_and_Maps.md) ![Day 5](../images/banners/day_1_9.png) @@ -37,7 +38,7 @@ - [Sorting string values](#sorting-string-values) - [Sorting Numeric values](#sorting-numeric-values) - [Sorting Object Arrays](#sorting-object-arrays) - - [💻 Exercises](#%f0%9f%92%bb-exercises) + - [💻 Exercises](#-exercises) - [Exercises: Level 1](#exercises-level-1) - [Exercises: Level 2](#exercises-level-2) - [Exercises: Level 3](#exercises-level-3) @@ -181,7 +182,7 @@ Instead of writing regular loop, latest version of JavaScript introduced lots of _forEach_: Iterate an array elements. We use _forEach_ only with arrays. It takes a callback function with elements, index parameter and array itself. The index and the array optional. ```js -arr.forEach(function(element, index, arr) { +arr.forEach(function (element, index, arr) { console.log(index, element, arr) }) // The above code can be written using arrow function @@ -222,7 +223,7 @@ console.log(sum) ```js const countries = ['Finland', 'Denmark', 'Sweden', 'Norway', 'Iceland'] -countries.forEach(element => console.log(element.toUpperCase())) +countries.forEach((element) => console.log(element.toUpperCase())) ``` ```sh @@ -235,10 +236,10 @@ ICELAND ### map -_map_: Iterate an array elements and modify the array elements. It takes a callback function with elements and index parameter and return a new array. +_map_: Iterate an array elements and modify the array elements. It takes a callback function with elements, index , array parameter and return a new array. ```js -const modifiedArray = arr.map(function(element, index) { +const modifiedArray = arr.map(function (element, index, arr) { return element }) ``` @@ -249,7 +250,7 @@ const modifiedArray = arr.map((element,index) => element); */ //Example const numbers = [1, 2, 3, 4, 5] -const numbersSquare = numbers.map(num => num * num) +const numbersSquare = numbers.map((num) => num * num) console.log(numbersSquare) ``` @@ -260,7 +261,7 @@ console.log(numbersSquare) ```js const names = ['Asabeneh', 'Mathias', 'Elias', 'Brook'] -const namesToUpperCase = names.map(name => name.toUpperCase()) +const namesToUpperCase = names.map((name) => name.toUpperCase()) console.log(namesToUpperCase) ``` @@ -280,9 +281,9 @@ const countries = [ 'Hungary', 'Ireland', 'Japan', - 'Kenya' + 'Kenya', ] -const countriesToUpperCase = countries.map(country => country.toUpperCase()) +const countriesToUpperCase = countries.map((country) => country.toUpperCase()) console.log(countriesToUpperCase) /* @@ -300,7 +301,7 @@ const countriesToUpperCase = countries.map(country => country.toUpperCase()); ``` ```js -const countriesFirstThreeLetters = countries.map(country => +const countriesFirstThreeLetters = countries.map((country) => country.toUpperCase().slice(0, 3) ) ``` @@ -315,7 +316,7 @@ _Filter_: Filter out items which full fill filtering conditions and return a new ```js //Filter countries containing land -const countriesContainingLand = countries.filter(country => +const countriesContainingLand = countries.filter((country) => country.includes('land') ) console.log(countriesContainingLand) @@ -326,7 +327,7 @@ console.log(countriesContainingLand) ``` ```js -const countriesEndsByia = countries.filter(country => country.includes('ia')) +const countriesEndsByia = countries.filter((country) => country.endsWith('ia')) console.log(countriesEndsByia) ``` @@ -336,7 +337,7 @@ console.log(countriesEndsByia) ```js const countriesHaveFiveLetters = countries.filter( - country => country.length === 5 + (country) => country.length === 5 ) console.log(countriesHaveFiveLetters) ``` @@ -351,10 +352,10 @@ const scores = [ { name: 'Mathias', score: 80 }, { name: 'Elias', score: 50 }, { name: 'Martha', score: 85 }, - { name: 'John', score: 100 } + { name: 'John', score: 100 }, ] -const scoresGreaterEight = scores.filter(score => score.score > 80) +const scoresGreaterEight = scores.filter((score) => score.score > 80) console.log(scoresGreaterEight) ``` @@ -364,11 +365,18 @@ console.log(scoresGreaterEight) ### reduce -_reduce_: Reduce takes a callback function. The call back function takes accumulator and current value as a parameter and returns a single value: +_reduce_: Reduce takes a callback function. The call back function takes accumulator, current, and optional initial value as a parameter and returns a single value. It is a good practice to define an initial value for the accumulator value. If we do not specify this parameter, by default accumulator will get array `first value`. If our array is an _empty array_, then `Javascript` will throw an error. + +```js +arr.reduce((acc, cur) => { + // some operations goes here before returning a value + return +}, initialValue) +``` ```js const numbers = [1, 2, 3, 4, 5] -const sum = numbers.reduce((accum, curr) => accum + curr) +const sum = numbers.reduce((acc, cur) => acc + cur, 0) console.log(sum) ``` @@ -383,7 +391,7 @@ _every_: Check if all the elements are similar in one aspect. It returns boolean ```js const names = ['Asabeneh', 'Mathias', 'Elias', 'Brook'] -const areAllStr = names.every(name => typeof name === 'string') +const areAllStr = names.every((name) => typeof name === 'string') console.log(arrAllStr) ``` @@ -394,7 +402,7 @@ true ```js const bools = [true, true, true, true] -const areAllTrue = bools.every(b => { +const areAllTrue = bools.every((b) => { return b === true }) @@ -412,7 +420,7 @@ _find_: Return the first element which satisfies the condition ```js const ages = [24, 22, 25, 32, 35, 18] -const age = ages.find(age => age < 20) +const age = ages.find((age) => age < 20) console.log(age) ``` @@ -423,7 +431,7 @@ console.log(age) ```js const names = ['Asabeneh', 'Mathias', 'Elias', 'Brook'] -const result = names.find(name => name.length > 7) +const result = names.find((name) => name.length > 7) console.log(result) ``` @@ -437,10 +445,10 @@ const scores = [ { name: 'Mathias', score: 80 }, { name: 'Elias', score: 50 }, { name: 'Martha', score: 85 }, - { name: 'John', score: 100 } + { name: 'John', score: 100 }, ] -const score = scores.find(user => { +const score = scores.find((user) => { return user.score > 80 }) console.log(score) @@ -458,10 +466,10 @@ _findIndex_: Return the position of the first element which satisfies the condit const names = ['Asabeneh', 'Mathias', 'Elias', 'Brook'] const ages = [24, 22, 25, 32, 35, 18] -const result = names.findIndex(name => name.length > 7) +const result = names.findIndex((name) => name.length > 7) console.log(result) // 0 -const age = ages.findIndex(age => age < 20) +const age = ages.findIndex((age) => age < 20) console.log(age) // 5 ``` @@ -473,7 +481,7 @@ _some_: Check if some of the elements are similar in one aspect. It returns bool const names = ['Asabeneh', 'Mathias', 'Elias', 'Brook'] const bools = [true, true, true, true] -const areSomeTrue = bools.some(b => { +const areSomeTrue = bools.some((b) => { return b === true }) @@ -481,11 +489,10 @@ console.log(areSomeTrue) //true ``` ```js -const areAllStr = names.some(name => typeof name === 'number') +const areAllStr = names.some((name) => typeof name === 'number') console.log(areAllStr) // false ``` - ### sort _sort_: The sort methods arranges the array elements either ascending or descending order. By default, the **_sort()_** method sorts values as strings.This works well for string array items but not for numbers. If number values are sorted as strings and it give us wrong result. Sort method modify the original array. It is recommended to copy the original data before you start using _sort_ method. @@ -506,13 +513,13 @@ As you can see in the example below, 100 came first after sorted in ascending or const numbers = [9.81, 3.14, 100, 37] // Using sort method to sort number items provide a wrong result. see below console.log(numbers.sort()) //[100, 3.14, 37, 9.81] -numbers.sort(function(a, b) { +numbers.sort(function (a, b) { return a - b }) console.log(numbers) // [3.14, 9.81, 37, 100] -numbers.sort(function(a, b) { +numbers.sort(function (a, b) { return b - a }) console.log(numbers) //[100, 37, 9.81, 3.14] @@ -523,7 +530,7 @@ console.log(numbers) //[100, 37, 9.81, 3.14] When ever we sort objects in an array. We use the object key to compare. Lets see the example below. ```js -objArr.sort(function(a, b) { +objArr.sort(function (a, b) { if (a.key < b.key) return -1 if (a.key > b.key) return 1 return 0 @@ -531,7 +538,7 @@ objArr.sort(function(a, b) { // or -objArr.sort(function(a, b) { +objArr.sort(function (a, b) { if (a['key'] < b['key']) return -1 if (a['key'] > b['key']) return 1 return 0 @@ -541,7 +548,7 @@ const users = [ { name: 'Asabeneh', age: 150 }, { name: 'Brook', age: 50 }, { name: 'Eyo', age: 100 }, - { name: 'Elias', age: 22 } + { name: 'Elias', age: 22 }, ] users.sort((a, b) => { if (a.age < b.age) return -1 @@ -568,7 +575,7 @@ const products = [ { product: 'potato', price: ' ' }, { product: 'avocado', price: 8 }, { product: 'coffee', price: 10 }, - { product: 'tea', price: '' } + { product: 'tea', price: '' }, ] ``` @@ -587,17 +594,17 @@ const products = [ 13. Use **_filter_** to filter out countries containing six letters and more in the country array. 14. Use **_filter_** to filter out country start with 'E'; 15. Use **_filter_** to filter out only prices with values. -18. Declare a function called getStringLists which takes an array as a parameter and then returns an array only with string items. -19. Use **_reduce_** to sum all the numbers in the numbers array. -20. Use **_reduce_** to concatenate all the countries and to produce this sentence: **_Estonia, Finland, Sweden, Denmark, Norway, and IceLand are north European countries_** -21. Explain the difference between **_some_** and **_every_** -22. Use **_some_** to check if some names' length greater than seven in names array -23. Use **_every_** to check if all the countries contain the word land -24. Explain the difference between **_find_** and **_findIndex_**. -25. Use **_find_** to find the first country containing only six letters in the countries array -26. Use **_findIndex_** to find the position of the first country containing only six letters in the countries array -27. Use **_findIndex_** to find the position of **_Norway_** if it doesn't exist in the array you will get -1. -28. Use **_findIndex_** to find the position of **_Russia_** if it doesn't exist in the array you will get -1. +16. Declare a function called getStringLists which takes an array as a parameter and then returns an array only with string items. +17. Use **_reduce_** to sum all the numbers in the numbers array. +18. Use **_reduce_** to concatenate all the countries and to produce this sentence: **_Estonia, Finland, Sweden, Denmark, Norway, and IceLand are north European countries_** +19. Explain the difference between **_some_** and **_every_** +20. Use **_some_** to check if some names' length greater than seven in names array +21. Use **_every_** to check if all the countries contain the word land +22. Explain the difference between **_find_** and **_findIndex_**. +23. Use **_find_** to find the first country containing only six letters in the countries array +24. Use **_findIndex_** to find the position of the first country containing only six letters in the countries array +25. Use **_findIndex_** to find the position of **_Norway_** if it doesn't exist in the array you will get -1. +26. Use **_findIndex_** to find the position of **_Russia_** if it doesn't exist in the array you will get -1. ### Exercises: Level 2 @@ -614,91 +621,94 @@ const products = [ 1. Use the countries information, in the data folder. Sort countries by name, by capital, by population 1. \*\*\* Find the 10 most spoken languages: - ````js - // Your output should look like this - console.log(mostSpokenLanguages(countries, 10)) - [(91, 'English'), - (45, 'French'), - (25, 'Arabic'), - (24, 'Spanish'), - (9, 'Russian'), - (9, 'Portuguese'), - (8, 'Dutch'), - (7, 'German'), - (5, 'Chinese'), - (4, 'Swahili'), - (4, 'Serbian')] - - // Your output should look like this - console.log(mostSpokenLanguages(countries, 3)) - [ - (91, 'English'), - (45, 'French'), - (25, 'Arabic') - ]``` - - ```` - -1. \*\*\* Use countries_data.js file create a function which create the ten most populated countries - - ````js - console.log(mostPopulatedCountries(countries, 10)) - - [ - {country: 'China', population: 1377422166}, - {country: 'India', population: 1295210000}, - {country: 'United States of America', population: 323947000}, - {country: 'Indonesia', population: 258705000}, - {country: 'Brazil', population: 206135893}, - {country: 'Pakistan', population: 194125062}, - {country: 'Nigeria', population: 186988000}, - {country: 'Bangladesh', population: 161006790}, - {country: 'Russian Federation', population: 146599183}, - {country: 'Japan', population: 126960000} - ] - - console.log(mostPopulatedCountries(countries, 3)) - [ - {country: 'China', population: 1377422166}, - {country: 'India', population: 1295210000}, - {country: 'United States of America', population: 323947000} - ] - ``` - -1. \*\*\* Try to develop a program which calculate measure of central tendency of a sample(mean, median, mode) and measure of variability(range, variance, standard deviation). In addition to those measures find the min, max, count, percentile, and frequency distribution of the sample. You can create an object called statistics and create all the functions which do statistical calculations as method for the statistics object. Check the output below. - - ```js - const ages = [31, 26, 34, 37, 27, 26, 32, 32, 26, 27, 27, 24, 32, 33, 27, 25, 26, 38, 37, 31, 34, 24, 33, 29, 26] - - console.log('Count:', statistics.count()) // 25 - console.log('Sum: ', statistics.sum()) // 744 - console.log('Min: ', statistics.min()) // 24 - console.log('Max: ', statistics.max()) // 38 - console.log('Range: ', statistics.range() // 14 - console.log('Mean: ', statistics.mean()) // 30 - console.log('Median: ',statistics.median()) // 29 - console.log('Mode: ', statistics.mode()) // {'mode': 26, 'count': 5} - console.log('Variance: ',statistics.var()) // 17.5 - console.log('Standard Deviation: ', statistics.std()) // 4.2 - console.log('Variance: ',statistics.var()) // 17.5 - console.log('Frequency Distribution: ',statistics.freqDist()) # [(20.0, 26), (16.0, 27), (12.0, 32), (8.0, 37), (8.0, 34), (8.0, 33), (8.0, 31), (8.0, 24), (4.0, 38), (4.0, 29), (4.0, 25)] - ``` - - ```sh - console.log(statistics.describe()) - Count: 25 - Sum: 744 - Min: 24 - Max: 38 - Range: 14 - Mean: 30 - Median: 29 - Mode: (26, 5) - Variance: 17.5 - Standard Deviation: 4.2 - Frequency Distribution: [(20.0, 26), (16.0, 27), (12.0, 32), (8.0, 37), (8.0, 34), (8.0, 33), (8.0, 31), (8.0, 24), (4.0, 38), (4.0, 29), (4.0, 25)] - ``` + ````js + // Your output should look like this + console.log(mostSpokenLanguages(countries, 10)) + [ + {country: 'English',count:91}, + {country: 'French',count:45}, + {country: 'Arabic',count:25}, + {country: 'Spanish',count:24}, + {country:'Russian',count:9}, + {country:'Portuguese', count:9}, + {country:'Dutch',count:8}, + {country:'German',count:7}, + {country:'Chinese',count:5}, + {country:'Swahili',count:4} + ] + + // Your output should look like this + console.log(mostSpokenLanguages(countries, 3)) + [ + {country: 'English',count: 91}, + {country: 'French',count: 45}, + {country: 'Arabic',count: 25}, + ]``` + + ```` + +2. \*\*\* Use countries_data.js file create a function which create the ten most populated countries + + ````js + console.log(mostPopulatedCountries(countries, 10)) + + [ + {country: 'China', population: 1377422166}, + {country: 'India', population: 1295210000}, + {country: 'United States of America', population: 323947000}, + {country: 'Indonesia', population: 258705000}, + {country: 'Brazil', population: 206135893}, + {country: 'Pakistan', population: 194125062}, + {country: 'Nigeria', population: 186988000}, + {country: 'Bangladesh', population: 161006790}, + {country: 'Russian Federation', population: 146599183}, + {country: 'Japan', population: 126960000} + ] + + console.log(mostPopulatedCountries(countries, 3)) + [ + {country: 'China', population: 1377422166}, + {country: 'India', population: 1295210000}, + {country: 'United States of America', population: 323947000} + ] + ``` + + ```` + +3. \*\*\* Try to develop a program which calculate measure of central tendency of a sample(mean, median, mode) and measure of variability(range, variance, standard deviation). In addition to those measures find the min, max, count, percentile, and frequency distribution of the sample. You can create an object called statistics and create all the functions which do statistical calculations as method for the statistics object. Check the output below. + + ```js + const ages = [31, 26, 34, 37, 27, 26, 32, 32, 26, 27, 27, 24, 32, 33, 27, 25, 26, 38, 37, 31, 34, 24, 33, 29, 26] + + console.log('Count:', statistics.count()) // 25 + console.log('Sum: ', statistics.sum()) // 744 + console.log('Min: ', statistics.min()) // 24 + console.log('Max: ', statistics.max()) // 38 + console.log('Range: ', statistics.range() // 14 + console.log('Mean: ', statistics.mean()) // 30 + console.log('Median: ',statistics.median()) // 29 + console.log('Mode: ', statistics.mode()) // {'mode': 26, 'count': 5} + console.log('Variance: ',statistics.var()) // 17.5 + console.log('Standard Deviation: ', statistics.std()) // 4.2 + console.log('Variance: ',statistics.var()) // 17.5 + console.log('Frequency Distribution: ',statistics.freqDist()) # [(20.0, 26), (16.0, 27), (12.0, 32), (8.0, 37), (8.0, 34), (8.0, 33), (8.0, 31), (8.0, 24), (4.0, 38), (4.0, 29), (4.0, 25)] + ``` + + ```sh + console.log(statistics.describe()) + Count: 25 + Sum: 744 + Min: 24 + Max: 38 + Range: 14 + Mean: 30 + Median: 29 + Mode: (26, 5) + Variance: 17.5 + Standard Deviation: 4.2 + Frequency Distribution: [(20.0, 26), (16.0, 27), (12.0, 32), (8.0, 37), (8.0, 34), (8.0, 33), (8.0, 31), (8.0, 24), (4.0, 38), (4.0, 29), (4.0, 25)] + ``` 🎉 CONGRATULATIONS ! 🎉 -[<< Day 8](https://github.com/Asabeneh/30DaysOfJavaScript/blob/master/08_Day/08_day_objects.md) | [Day 10 >>](https://github.com/Asabeneh/30DaysOfJavaScript/blob/master/10_Day/10_day_Set_and_Map.md) +[<< Day 8](../08_Day_Objects/08_day_objects.md) | [Day 10 >>](../10_Day_Sets_and_Maps/10_day_Sets_and_Maps.md) diff --git a/09_Day/09_day_starter/data/countries_data.js b/09_Day_Higher_order_functions/09_day_starter/data/countries_data.js similarity index 100% rename from 09_Day/09_day_starter/data/countries_data.js rename to 09_Day_Higher_order_functions/09_day_starter/data/countries_data.js diff --git a/09_Day/09_day_starter/index.html b/09_Day_Higher_order_functions/09_day_starter/index.html similarity index 100% rename from 09_Day/09_day_starter/index.html rename to 09_Day_Higher_order_functions/09_day_starter/index.html diff --git a/09_Day/09_day_starter/scripts/main.js b/09_Day_Higher_order_functions/09_day_starter/scripts/main.js similarity index 100% rename from 09_Day/09_day_starter/scripts/main.js rename to 09_Day_Higher_order_functions/09_day_starter/scripts/main.js diff --git a/10_Day/10_day_Set_and_Map.md b/10_Day_Sets_and_Maps/10_day_Sets_and_Maps.md similarity index 84% rename from 10_Day/10_day_Set_and_Map.md rename to 10_Day_Sets_and_Maps/10_day_Sets_and_Maps.md index 65067c9a8..6d0064cc2 100644 --- a/10_Day/10_day_Set_and_Map.md +++ b/10_Day_Sets_and_Maps/10_day_Sets_and_Maps.md @@ -1,5 +1,5 @@

30 Days Of JavaScript