This course teaches Ruby for beginners by demystifying the basics of Ruby programming, laying the foundation for becoming a proficient Ruby developer.

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ruby

The Ruby programming language, known for its simplicity and readability, is perfect for programming beginners. This course introduces core programming concepts and problem-solving techniques, providing a solid foundation in Ruby. You’ll start with basic program development, decision-making, loops, strings, and arrays, reinforced by hands-on exercises, quizzes, and coding challenges.
By the end of the course, you’ll gain essential skills that can advance your career as a Ruby developer in the tech industry.

Learn Ruby

## Built-in methods for strings
Ruby provides various built-in Methods for dealing with strings. These methods are collectively called **string methods**.




> **Note:** All string methods return a new string without changing the original one.

There are numerous tasks related to strings that make it easy for programmers to perform routine tasks. This section will provide examples and results of some commonly used string methods.

### The methods related to case change
These methods change the letter case of the text stored in a string (say, from lowercase to uppercase). Let’s use an example program to explore case changes.

* The `capitalize()` method converts the _first_ character of the string to uppercase.
* The `downcase()` method converts _all_ characters in the string to lowercase.
* The `swapcase()` method swaps the letter case of the characters in a string—downcase becomes the uppercase and vice versa.
* The `upcase()` method converts _all_ characters in a string to uppercase.

# The methods related to case change
print("'capitalize()' converts the first letter of string: ","educative".capitalize(),"\n")
print("'downcase()' converts the string to lowercase: ","EDUCATIVE".downcase(),"\n")
print("'swapcase()' swaps the cases of letters: ","eDUCATIVE".swapcase(),"\n")
print("'upcase()' converts the string to uppercase: ","educative".upcase(),"\n")

### The search-related methods
These methods search for the occurrence of text in a string. Let’s use an example program to explore searches.

* The `end_with?` method checks for text at the _end_ of a string and returns `true` or `false`.
* The `index` method searches for text in the string and returns the index of the first occurrence.
* The `include?` method searches for text in the string and returns `true` or `false`.
* The `count` method searches for characters in the string and returns the number of occurrences.
* The `gsub` method searches for _all_ occurrences of a text in the string, replaces it with different text, and returns the new string after replacement.
* The `start_with?` method checks for text at the _start_ of a string and returns `true` or `false`.
* The `empty?` method checks if a string is empty or not.


# Search-related methods on strings
print("'end_with?' return true if string ends with 've': ", "educative".end_with?('ve'),"\n")
print("'index' returns the index of first occurrence of 'e': ", "educative".index('e'),"\n")
print("'include?' returns true if 'e' is present in the string: ", "educative".include?('e'),"\n")
print("'count' return the count of letter 'e' in the string: ", "educative".count('e'),"\n")
print("'gsub' replace the 'e' with '..E..': ", "educative".gsub('e','..E..'),"\n")
print("'start_with?' return true if string starts with 'edu': ", "educative".start_with?('edu'),"\n")
print("'empty?' return true if string is empty: ", "".empty?,"\n")

## Built-in methods for arrays
Ruby provides various built-in functions for dealing with arrays, usually termed **array methods**, which programmers use to perform routine tasks. Let’s use practice programs to learn these built-in methods related to arrays.



### The value-inserting methods
The following methods are used to add values to arrays:

* The `append()` method adds an element at the end of the array. If we try to append another array, it’s added as a single element, making a nested array.
* The `clone()` method creates a copy of an existing array. Future updates to the original array don’t affect the copy. This differs from the assignment operator `=`, which only creates a reference to an existing array. In the case of assignment, any change to the original array is reflected in the reference. This difference is illustrated in the code below.
* The `push()` method appends multiple elements to the end of the array. This method can append an array to another array, element by element.
* The `insert()` method adds an element at a specified position in the array.


# The value-inserting methods
a = [1,2,3]
b = [8,9]
print("Array a: ",a,"\n")
print("Array b: ",b,"\n")

print("\nAppending 4 in array a","\n")
a.append(4) # Appending 4 in array a
print("Array a: ",a,"\n")

print("\nAppending complete array b as subarray in a ","\n")
a.append(b) # Appending complete array b as subarray in a 
print("Array a: ",a,"\n")
print("Array b: ",b,"\n")

print("\nCreating a new copy of array b in array c","\n")
c = b.clone() # Creating a new copy of array b in array c
print("Array b: ",b,"\n")
print("Array c: ",c,"\n")

print("\nReferencing: array d is an other name of array b","\n")
d = b # Referencing: array d is an other name of array b
print("Array d: ",d,"\n")

print("\nAppends all members of b to array c","\n")
c.push(b) # Appends all members of b to array c
print("Array c: ",c,"\n")

print("\nInserting 15 at index 1 in array b","\n")
b.insert(1,15)# Inserting 15 at index 1 in array b
print("Array b: ",b,"\n")
print("Array d: ",d,"\n")

### The value-removing methods
The following methods are used to remove values from arrays:

* The `clear()` method removes all the elements from the array.
* The `pop()` method removes the last element from the array.
* The `delete()` method removes the specified value from the array.
* The `delete_at()` method removes the value from the specified index.

# The value-removing methods
d = [1,2,3,4,5,6]
print("array d:",d,"\n")
print("\nRemoving value from the end of array d using pop() function","\n")
d.pop(1) # Removing value from the end of array d using pop() function
print(d,"\n")

print("\nRemoving the value 3 from array d using delete() function","\n")
d.delete(3) # Removing the value 3 from array d using delete() function
print(d,"\n")

print("\nRemoving the value at index 1 from array d using delete_at() function","\n")
d.delete_at(1) # Removing the value at index 1 from array d using delete() function
print(d,"\n")

print("\nRemoving all values array d using clear() function","\n")

d.clear() # Removing all values array d using clear() function
print(d,"\n")

### The search-related methods
The following methods are used to search for values in arrays:
* The `count()` method searches for an element in the array and returns the number of occurrences.
* The `index()` method searches for an element in the array and returns the index of the first occurrence.

# The search-related methods
e = [1,1,3,40,4,4,4,5]
print('The original array:',e,"\n")
print("The number of 1s in the array:",e.count(1),"\n")
print('The index of 40 in the array:',e.index(40),"\n")

### The arrangement-related methods

The following methods are used to change the arrangement of values in arrays:

* The `reverse()` method reverses the order of the array.
* The `sort()` method sorts the array.


# The arrangement-related methods
f = [1,1,30,40,4,4,40,5]
print('The original array:',f,"\n")
f = f.reverse()
print('The array after reversing the elements:',f,"\n")
f = f.sort()
print('The array after sorting in increasing order:',f,"\n")

# Built-in methods for strings
Ruby provides various built-in Methods for dealing with strings. These methods are collectively called **string methods**.




> **Note:** All string methods return a new string without changing the original one.

There are numerous tasks related to strings that make it easy for programmers to perform routine tasks. This section will provide examples and results of some commonly used string methods.

## The methods related to case change
These methods change the letter case of the text stored in a string (say, from lowercase to uppercase). Let’s use an example program to explore case changes.

* The `capitalize()` method converts the _first_ character of the string to uppercase.
* The `downcase()` method converts _all_ characters in the string to lowercase.
* The `swapcase()` method swaps the letter case of the characters in a string—downcase becomes the uppercase and vice versa.
* The `upcase()` method converts _all_ characters in a string to uppercase.

## The search-related methods
These methods search for the occurrence of text in a string. Let’s use an example program to explore searches.

* The `end_with?` method checks for text at the _end_ of a string and returns `true` or `false`.
* The `index` method searches for text in the string and returns the index of the first occurrence.
* The `include?` method searches for text in the string and returns `true` or `false`.
* The `count` method searches for characters in the string and returns the number of occurrences.
* The `gsub` method searches for _all_ occurrences of a text in the string, replaces it with different text, and returns the new string after replacement.
* The `start_with?` method checks for text at the _start_ of a string and returns `true` or `false`.
* The `empty?` method checks if a string is empty or not.


# Built-in methods for arrays
Ruby provides various built-in functions for dealing with arrays, usually termed **array methods**, which programmers use to perform routine tasks. Let’s use practice programs to learn these built-in methods related to arrays.



## The value-inserting methods
The following methods are used to add values to arrays:

* The `append()` method adds an element at the end of the array. If we try to append another array, it’s added as a single element, making a nested array.
* The `clone()` method creates a copy of an existing array. Future updates to the original array don’t affect the copy. This differs from the assignment operator `=`, which only creates a reference to an existing array. In the case of assignment, any change to the original array is reflected in the reference. This difference is illustrated in the code below.
* The `push()` method appends multiple elements to the end of the array. This method can append an array to another array, element by element.
* The `insert()` method adds an element at a specified position in the array.


## The value-removing methods
The following methods are used to remove values from arrays:

* The `clear()` method removes all the elements from the array.
* The `pop()` method removes the last element from the array.
* The `delete()` method removes the specified value from the array.
* The `delete_at()` method removes the value from the specified index.

## The search-related methods
The following methods are used to search for values in arrays:
* The `count()` method searches for an element in the array and returns the number of occurrences.
* The `index()` method searches for an element in the array and returns the index of the first occurrence.

## The arrangement-related methods

The following methods are used to change the arrangement of values in arrays:

* The `reverse()` method reverses the order of the array.
* The `sort()` method sorts the array.


Learn to use popular built-in Methods related to strings and arrays in Ruby.


Built-in String and Array Methods

Learn to use popular built-in Methods related to strings and arrays in Ruby.

About the Course

Ruby Basics

Loops in Ruby

Ruby Strings and Arrays

Ruby Methods

Wrap Up

Built-in String and Array Methods