A **lambda function** is an anonymous function, which means it is a function without a name.

In Python, a typical function is defined with the `def` keyword. The **`lambda`** keyword is used to define an anonymous function. 

#      
## Syntax
```py
lambda arguments: expression
```



> A lambda function can take in any number of arguments, but only one expression.

#    
## Code

### A lambda function with one argument:

#     
## 
### A lambda function with multiple arguments:


Max = lambda y, z : x if(y > z) else z
print(Max(12, 29))

#     
## Problem statement
Find the odd numbers in the list using a lambda function.

## Code

# A python code to find odd numbers in a list
# using Lambda function
# list of numbers from 1 to 11 
myList = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11] 
# lambda function 
odd_nos = list(filter(lambda a: (a % 2 != 0), myList))
print(" Odd numbers in the list : \n", odd_nos) 

#     
## Explanation

In the code above, we create a list of numbers (1 to 11).
Next, we use a lambda function to check for odd numbers in the list. 
Finally, we extract the odd numbers from `mylist[]` and add them to a new list called `odd_nos`.

#    
## How to use a Lambda function as an argument to a higher-order function

A **higher-order function** is a function that passes a function as a parameter to another function, meaning it takes a function (or functions) as an argument. It is a first-class function.
The three commonly used higher-order functions are `map()`, `filter()`, and `reduce()`.

### The `map()` function

**`map()`** is used to apply a given function to each element of an iterable and return an iterable of results in the same order. `map()` takes a function and iterable(s) (e.g. list, tuple) as the second argument that is passed sequentially to the function.

### Syntax
```
map(func, iter)
```

# map() takes Lambda function as an argument
myList = [0, 2, 4, 6, 8, 10] 
newList = list(map(lambda x: (x*5), myList))
print("Original list: \n", myList)
print ("The new list: \n", newList)

#      
##     
### The `filter()` function
**`filter()`** is a function that creates an iterable from an old one by matching every element in the new iterable to a predicate that returns a Boolean value. `filter()` takes two arguments.

 
### Syntax
```
filter(func, iter)
```


#      
##     
### The `reduce()` function
**`reduce()`** is a function that folds or reduces an iterable into a single value. `reduce()` takes two arguments.

 
### Syntax

```
reduce(func,iter)
```

# # reduce() takes Lambda function as an argument
from functools import reduce
a = reduce(lambda x, y: x+y, range(1,51))
print("The value of a is ", a)

# using reduce to concatenate string
print(reduce(lambda x, y: x+y, ["Edu", "ca", "tive", " shot"]))

How to use Lambda functions to solve problems in Python

Syntax

Code

A lambda function with one argument:

A lambda function with multiple arguments:

Problem statement

Code

Explanation

How to use a Lambda function as an argument to a higher-order function

The map() function

Syntax

The filter() function

Syntax

The reduce() function

Syntax

The `map()` function

The `filter()` function

The `reduce()` function