These functions are commonly used in functional-style python programming.

These functions are most often used in conjunction with the anonymous ( lambda ) function, but you can use it with a normal function which defines by ( def ) key word.

map( ) , reduce( ) and filter( ) all were available in python 2 , but in python 3 reduce( ) function was moved to functools module.

Lambda ( anonymous ) Function

Let’s first understand what is an anonymous function in python is,

This function starts with keyword lambda and has arguments and expressions both separated by ( : )

lambda arguments : expression

Ex :

This will be same as

As you can see lambda function does not require any name that’s why it is called an anonymous function.

We use this function when we require a nameless function and in the case of functional programming.

One more thing I should mention is what is an iterable ?

iterable is any object which can be iterated using for loop,

ex: list, string, dictionary, tuple

map ( )

Syntax : map(function, iterable, . . . )

Here,
the function will be performed on each element of iterable.

Also, you should know that map() will return an iterator, not a particular value, so its value can be used whenever requires.

You can pass more than one iterable in the map function, but the important thing to remember is in case of different sizes of the iterable map will stop when it consumes the shortest iterable.

Ex: let’s find square of every element from list.

All this function does the same thing it will return the square of 1 to 10 number, but as you know it will return an iterator it will be something like this,

But you can pass map() in list() function or use for loop to see result,

map( ) [ with multiple iterable ]

Second time see it is stop at the smallest iterable which is range(4).

filter( )

Syntax : filter(function,iterable, . . . )

Unlike map(), the filter() function will not transform the input value into a new value, but it will return a value that matches the condition mentioned in the function.

As the name suggests it will filter out elements from iterable based on certain conditions.

Ex : let’s find odd and even numbers from a list of elements.

reduce( )

Syntax : reduce(function, iterable)

As map() function will perform function on each element of iterable one by one,
In reduce() this function will cumulatively perform operations specify by the function,
This function will return an only single value,

Also, we have to import it from the functools module in python3

Let’s see how it works,

Let’s understand what just happen,
This will,
Starts at a, b which will be 1, 2
performs a + b which will be 3
Now a, b will be the result of the previous a + b which is 3, and next element in the list
Let’s understand it better in the below image

Now, map() and filter() functions returns an iterator which you access by loop or list() function which is also a loop inside,

but also you can access it’s element by next() function like this,

In this article, I have explored the very powerful and useful built-in function of python,

Map( )
→ map(function,iterable, . . . )
→ Perform function on each element of an iterable
→ Returns an iterator
→ Generate a new value for each element of an iterable
→In the case of multiple iterable, it will stop at the exhaustion of the smallest iterable.

Filter( )
→filter(function,iterable, . . . )
→Perform function on each element of an iterable
→Returns an iterator
→Returns Values that meet certain criteria defined by the function

Reduce( )
→reduce(function,iterable)
→Cumulatively performs operations specify by the function
→Return single value

Let’s see how much things get complicated if you decide that you don’t want to use this built-in function or maybe you don’t know about that.
An Example with and without the use of a map

Ex :

4521369741 → you have find sum of this numbers until it’s an single digit number.
Like this : 4 + 5 +2 +1 + 3 + 6 + 9 + 7+ 4 + 1 = 42 > 4 + 2 = 6 ( output )

you know what, I have written that code by myself when I don’t know about this fuction exists but now I know this function and you too.

“If you have an easy way around things that will give the same result, don’t waste your time to build the different way, it will just waste your time and energy.”

But It might be possible that you don’t know that an easy way exists for certain problems, but if you explore enough you will eventually find one.

KEEP LEARNING & KEEP GOING

Built-in Python functions map( ), filter( ) & reduce( ) , you should literally learn right now. was originally published in Quick Code on Medium, where people are continuing the conversation by highlighting and responding to this story.

You just can’t do everything by yourself nowadays, if you want to get more out of your day automate things, automate things you every day do so you don’t have to do it.

Things like Backup of important data, System logs, Running Certain scripts.

You can schedule jobs in Linux by using crontab, it’s a software utility that comes in every UNIX-like operating system to schedule tasks at a particular time.

Cron names after the Greek word “Chronos ” which means time. It’s the list of commands that execute tasks as per the specific schedule.

crontab is an editor for the list of tasks that you want to schedule.

Syntax of crontab

* * * * * command

* * * * * /path/to/script.sh

Here asterisks (* * * * *) is used for matching of minutes, hour, day of the month, the month of the year, day of the week.

The command could be a script that you want to execute at a particular time.

Let’s look at the commands to edit, list, delete jobs in crontab.

Edit in crontab

crontab -u <your_username> -e

or

crontab -e

For the first time, it will ask you to choose an editor you can choose nano which is very easy to use and comes with every Linux system.

Example 1 : I want to send a Linux notification to remind me to blink my eyes as I’m working on my laptop most of the time — and science says that you forgot to blink your eyes often while working on the screen — which is true.

So let’s say I want to send that notification every 25 minutes.

Command will be:

It’s a notification to Linux and has nothing to do with crontab.
Notify-send will expect two arguments:

1. Title of the Notification
2. 2. Body of the Notification

So “👀 Eye Health” is Title and “Remember to blink !!!” is Body

XDG_RUNTIME_DIR=/run/user/$(id -u)— Here, XDG_RUNTIME_DIR is an environment variable that is set automatically when you log in. When you run notify-send command from crontab you have to specify this variable — as it allows the program to store temp files in user dir. But when you give any script or command that does not require interaction with the display you don’t have to specify it.

* * * * * — This will execute every minute, for each hour, for every day for every month for every year.

But you want to execute this command every 25 minutes. So you can do this by dividing minute matching by 25. It will be:

*/25 * * * *

/ →for step value
- → for range vaule
, → for seprating value

If you want to get a deeper understanding of this matching checks out the below website.

You can find value for ( * * * * * ) from here https://crontab.tech/

So this will send a notification every 25 min.

Example 2: You can save output or any runtime error of crontab in txt file.

So crontab will run every day at 12:45 and send echo command output in the crontab_log.txt file

Remember:
> → single means it will create a new file for if not exist and overwrite the output. ( overwrite )
>> → double means it will create a new file if not exists and append the output. ( append )

Listing all tasks in crontab

This will list all the jobs written in the crontab for that particular user if not specified it will run for active logged-in user.

crontab -u <your_username> -l

or

crontab -l

Removing crontab jobs

This will remove the entire list of tasks.

crontab -r

There are some built-in strings in crontab.

@hourly → command →will run command every hour ( 0 * * * * )
@midnight → ( 0 0 * * *)
@daily → ( 0 0 * * *) same as midnight
@weekly → ( 0 0 * * 0)
@monthly →( 0 0 1 * *)
@yearly →(0 0 1 1 *)
@reboot →run cron job at every reboot

Example 3: Running python script using crontab

This will run the backup.py python file every day at 10:45 AM

Example 4: Running bash script using crontab

Let’s see how to change mac address in Linux automatically

Here I have change-mac command configured to run my changing mac address bash script.

Now follow these series of command

Summary

→ cron is used to schedule jobs in Linux OS
→ crontab is used to edit , list , remove crontab in Linux for cron.
→ crontab -e → for edit
→ crontab -l → for listing jobs
→ crontab -r → fro removing crontab
→ Some predefined strings like @daily ( 0 0 * * * )

Resources

1. Shell Script code for changing mac address: https://github.com/techdobz/scripts

2. Find value of (* * * * *) Crontab syntax : https://crontab.tech/

Scheduling Cron Tasks in Linux was originally published in Better Programming on Medium, where people are continuing the conversation by highlighting and responding to this story.

Linux is the best-known and most used operating system,
Major Linux distributions are,
Linux Mint, Debian, Ubuntu, Archlinux, Fedora, Opensuse, centos, and FreeBSD

Many Linux distributions provide graphical user interfaces but you should also know how to work with the Linux terminal for that you should know basic commands of Linux OS.

Here are 6 essential commands which can make you better at Linux systems.

1. alias

This command allows you to define temporary aliases in your shell session.
It’s like variables in programming but instead of storing a value/string in the variable, you will store the command in a variable.

syntax :

alias [option] [name]='[value]'

usage :

alias c=’clear’

output :

Reverse alias with unalias command

usage :

unalias c

output :

2. kill

The kill command sends a signal to particular processes or a process group, causing them to act according to that signal.
Default signal when none specified : -15 ( -TERM )
The most common signal used in kill are :
1 ( HUP ) — Reload a process
9 ( KILL ) — kill a process
15 ( TERM ) — stop a process

To get a list of all available signals, we have to invoke -l option

kill – l

output :

usage :

Find process id of a particular process

commands : top, pidof, ps, pgrep

ex :

pidof atom

output :

10607 10531 10512 10499 10474 10472 10471 10468

next command :

kill -9 10607 10531 10512 10499 10474 10472 10471 10468

or 

kill -9 $(pidof atom)

3. man

This command is very essential because it is a manual of all the commands in Linux.
You can use this command to see another command syntax, usage, and what that command does.

usage :

man ls

output :

4. chmod

This command allows you to change the permission of any files.

The Basic permissions are

r ( read ), w ( write ), x ( execute )

The most common use of this command is, execute permission

syntax :

chmod [OPTION]... MODE[,MODE]... FILE...

usage :

chmod +x change.sh

ls -l (this command allows you to see the permissions of a particular file)

ls – l change.sh

output :

-rwxrwxr-x 1 dobz dobz 104 Dec  6 08:14 change.sh

Here, First rwx -> owners, second rwx -> groups, third rwx -> others

5. top

This command is an all information-packed dashboard, it will show all ongoing activity on your Linux system.

usage :

top

output :

This has two areas
1. summary area ( Memory info )
2. task area ( processes )

6. common all-time use commands

mkdir —To make a directory ( ex: mkdir tech_dobz )
cd — Change directory ( ex: cd tech_dobz/ )
pwd — Show current working directory ( ex: pwd )
touch — To make files ( ex: touch sample.txt )
ls — To list all the files and directories ( ex: ls )
rm — To delete the file or directory ( ex: rm sample.txt )
cd .. — To get into the previous directory ( ex: cd .. )

output :

“I’m not a great programmer; I’m just a good programmer with great habits.” — Kent Beck

Learning is a never-ending Journey you have to learn new things to cope up with this era.
Build a habit of learning new things, whether it’s just for 15 min a day.

6 essential commands to get better at Linux system, you should know was originally published in Dev Genius on Medium, where people are continuing the conversation by highlighting and responding to this story.

Let me ask you a question “how many hours do you think ?”

You might say I don’t know or I have never thought about that, but guess what you are thinking all the time, even right now you are thinking of how many hours you think every day. OK, I admit that’s my fault that you are thinking it.

You are thinking when,

When you are scrolling your social media.

“ how many hours I wasted on this, I should stop wasting any more time now and study ”

When you are eating.

“ Hey, I’m on diet I shouldn’t eat this, how many calories I will get from eating this, should I eat this ? ”

When you are working.

“ I should stop working now it’s been hours, you know what let’s watch some Netflix and play video games. ”

So don’t say that you don’t think that much,

It’s good that we are thinking. That proves that we are human not animals, even animals don’t think that much while eating.

There are two types of thoughts POSITIVE or NEGATIVE.

Worrying,

complaining too much,

Regretting,

playing Blaming games,

anger.

These are all examples of Negative thoughts. We can agree on that.

Working on the project,

Studying, Setting goals,

Making decisions,

Problem-solving.

These are all examples of Positive thoughts. We can agree on that.

Most self-help content will say that you should think, 2x more positive than negative.

you will agree on this, if you use your brain to overthink little things, you will not be able to use it when you most need it.

There is a very great saying in stoic Philosophy

“We suffer more often in imagination than in reality” — Seneca

If you think then you will imagine things, If that thinking is negative you will suffer in your imagination you will force to think worst possible results of your actions and because of that, you will create fear for that thing, and next time you will never try to do it again.

You became what you thought every day.

Like Marcus Aurelius said in his book meditations

“ Our life is what our thoughts make it. ” — Marcus Aurelius

Quality of your life depends on quality of your thoughts , but people assume that we are our thoughts.

That’s a very wrong assumption to make, you are not your thoughts,

let me explain if you think you are lazy, that means you become lazy right? NO, it doesn’t mean you are lazy.

You say that you can’t control your thinking or stop it from happening and you say I think it’s just me who thinks this much.

But No it’s not you everyone is the same after all we all are human by nature, the main difference between you and them, they know how to control their thoughts better than other people.

The more you stop it from happening, the probability of happening will increase by 95 %.

So you just can’t stop thinking all of a sudden but what you can do is observe your thoughts and then decide whether you want to let it go or you should think about it.

Living in the present moment can help you overcome overthinking.

What you can do to live in the present moment?

1. Be more aware of yourself.

Start by realizing that too much thinking can vanquish the purpose.

2. Start by observing your thoughts.

Whenever you start thinking of something, start by observing it instead of just thinking endlessly.

3. limit your thinking for a particular period.

If you are working on a project just think about that project only while you working on it.

If you are eating you don’t need to think so just focus on eating.

If you are doing journaling, then all you need is 5–10 minutes of thinking time that’s it.

I’m just a random person sharing my thoughts on what overthinking does to your brain. You don’t need to listen to me, and I’m not going to force you to do it also, is I can’t do it if I want to.

It’s your life and you have to decide for yourself nobody is coming to save you or help you, yes, many people like me will say what to do but it’s up to you whether you want to do it or not.

So start applying whatever you have learned from this post.

DO IT!

DO IT NOW!

THERE IS NO TOMORROW!

1. Never Underestimate Others and Overestimate yourself

“Smart people underestimate the ordinarity of ordinary people.” — Yukihiro Matsumoto

It’s like the saying “ Never Judge a Book by its cover ”, you can’t judge any person by their appearance, behavior, or education, you have no idea what he/she can do.

The same goes for your self never overestimate yourself and think that no one can beat you, you are the best, now here comes ego, and when you are in your false perception of yourself someone will give you checkmate.

2. Always plan Ahead of time.

Life is uncertain, you have no idea what will happen tomorrow, it’s not always as you planned, but you can predict your future by taking the right action in your present self.

“A good plan is like a road map: it shows the final destination and usually the best way to get there.”- H. Stanely Judd

You should know the consequences of your actions in the future. If you are playing games and watching Netflix all day and wasting your time like you don’t care guess what your future will be the same as yours today.

I’m not saying you should sit down and plan for the future all the time even in chess you think that you are ahead of your opponent by 2 steps but guess what it might be possible that your opponent is ahead of you by 5 steps you never know.

3. Learnt from Past make a move in present for future gain.

“ Life can’t ever be all bad or all good. You know, eventually, things have to come back to the middle.”

Regression to the mean : the tendency of things to go back to normal state.

You might not always win in life, But you can’t stop by one or two failures in life you have to make a move to learn from your past mistake.

You can’t expect a different result by same actions, you just can’t do that, you have to think differently and take different actions so that you don’t have any regrets in future

4. You have to sacrifice something if you want to gain something.

No one will win in chess with all its 16 pieces remaining alive, if you want to kill your opponent knight you might have to sacrifice your bishop.

“ There is no progress or accomplishment without sacrifice. ”

In the same way, you have to choose whether you want to play video games now or you want to work on your project, you don’t have (enough time) for everything, you have to give up one thing.

5. speak with your actions.

You know what nobody wants to listen to your nonsense of what you know and nobody care, so don’t waste your time on doing sh*t that nobody gives a f**k about just keep doing your work and you don’t have to speak anything.

“ Actions speak louder than words; let your words teach and your actions speak. ”

If you are a CEO of a company and someone wants to join your company, let me ask you one thing, Are you going to believe what I say or do you want to see what I can do.

6. you have to create Opportunities.

If you don’t have the opportunity create one by yourself. You might not get an opportunity automatically so don’t wait for your opponent to make mistake and you will get your move, you can create it by sacrificing your piece and creating a trap for your opponent.

“ Creating opportunities means looking where others are not. ” — Mark Cuban

In life also you don’t have to wait for the right moment to arrive to show your potential cause it might now come and you will wait forever so don’t be stupid and create one by yourself.

Now Implement it in your life.

Remember one thing in life knowledge is power but implementation is a superpower you are not going to improve if you don’t change your habits and implement what you have learned.

Even you don’t know how many times you may have said you don’t have time.

you think you don’t have time because you don’t know how to manage it, often you waste your time on doing things that don’t even 1% closer to your goals.

Sometimes you take a whole day doing just 2–3 hours work and here is a thing you don’t even realize until the end of the day and then you decide you will do better tomorrow, but guess what your tomorrow will be the same as your today.

Humans are terrible at planning and poor judges of how long some tasks will take.

we often say that I’ll be there in 2 minutes and it usually means 10 minutes for us.

What you can do to get more time? ( I’m you are not gonna get 25 hours 😅 )

Time blocking system

Time blocking is a technique in which you create a time window let’s say 15 min window, now predict how many blocks a particular thing will take.

Let’s say the 3 most important tasks today.
1. I have to write a Blog script for the next post.
2. I have to write a programming script for my client.
3. complete 2 modules from a course.

If I start doing things randomly it might take me a whole day to complete just these 3 tasks but in time blocking technique
Blog script -> 2 , programming script -> 2 , course -> 3

so I will need only 6 blocks ( 1:30 hour ), in this way I can complete my tasks fast. Just try to control your focus on 1 block each time.

The way we spend our time defines who we are. — Jonathan Estrin

Let me tell you Time management is overrated you don’t need lots of methods and techniques to control your time.

if I say don’t think of a pink elephant 🐘 , I’m pretty sure that you are thinking of it right now.
The more you try to control things the more it gets out of control.

Start Saying NO

“ Your time is limited, so don’t waste it living someone else life “ — Steve jobs

You don’t have to say Yes to every single thing that comes in your way.

You might help someone with their work or take responsibility for doing something for them by your nature.

Remember at the end of the day nobody gives sh*t, you don’t have to be nice to everyone.

Track Your Time

Now if I want you to do some project for me you need to know the requirements right without it you can’t do it.

The same thing goes for a time also you need to know where you are wasting your time for that you have to track it so you can avoid doing the same mistake.

Now for this, you don’t have to do detailed research and again waste time here 😅.

Start tracking with tools like screen and apps time monitor which you can find in your phone settings.

In this article on time,

1. Use a time blocking system to complete your tasks.
2. Don’t say yes to everything and overwhelm yourself to look good in others people’s eyes.
3. Track your time to eliminate the most time-consuming things.

Often you know what you want to do, which next project you have to do, you have to prepare for the next upcoming exam but, you end up doing something else at the end of the day.

Our brain is wired in survival mode for centuries, so if it’s not a life or death situation, you feel so bored or tired to get things done.

“The more important a call or action is to our soul’s evolution, the more Resistance we will feel toward pursuing it. ” — Steven Pressfield

So you are going to face resistance if you want to do something but your brain will choose not to do it because it is hooked to getting dopamine from an instant.

Why do you do that?

There is an economic theory called Time Inconsistency which can help us understand why you do this ( procrastination ).

Time Inconsistency

It states that you have to sacrifice now for the future gain but your brain doesn’t see the future gain, it prefers watching NETFLIX, endless scrolling on social media it wants instant gratification.

That’s why your ability to delay gratification is one of the biggest determinations when it comes to procrastination

Ex :

Marshmallow Experiment

An experiment was done by Stanford University in which children were given a marshmallow if they don’t eat it for the next few minutes they will get another one.

The children who were willing to delay gratification ended up having higher SAT scores, lower likelihood of obesity, and generally better scores in the range of other life measures.
 — Stanford University

At this time we all want instant pleasure in our life that’s why new generation innovators come in place and invented Tik-tok, Instagram reels, and Youtube shorts. You will get an instant dose of dopamine from this type of content.

No doubt some creators are using these platforms for sharing great knowledge, but many people are making videos from which you get more dopamine and you get addicted to it.

This will reduce your attention span so you want something new every few minutes you will become less focused on your tasks.

what you can do?

“The secret to getting ahead is getting started.”
― Mark Twain

1. Start with finding what you want to accomplish on a particular day.
2. Break down tasks into little chunks so you can focus more.
3. Make tasks easy to start.
4. Schedule everything so you don’t have any reason to postpone anything.

Two things matter the most when it comes to laziness and if you can improve just a little bit every day in these two things you can do a lot better in life.

Lack Of Clarity

let’s face it,

In his book, Atomic habit James clear said that

“Many people think they lack motivation, but in reality, they lack clarity” — James Clear

First, you have to know what you want to do on a particular day, without that knowledge you will end up wasting your time on things that do not matter.

How you can do it?

Lots of people are saying you should make a to-do list of tasks that you want to do, I’m not saying that they are wrong but here is a thing this list does not work at least for me.

Why? Cause you may end up getting 10–15 tasks on the list, you will get overwhelmed by seeing it or you will complete the less important tasks first.

What you can do instead?

Make an A-B-C-D-E list, in this way you will focus only on a particular set of the list, so if you can’t complete the whole list you don’t have to worry because you already have completed the most important tasks.

You Think You Have Time

When it comes to time we invest it without calculating loss.

The trouble is, you think you have time.

So if you think you have time then you will end postponing your tasks to tomorrow, and that tomorrow will never come, this will raise procrastination

Most people will always complete their tasks the day before the due date, A procrastinator does not realize that how much time he is wasting because it is a habit for him.

“Yes, you can — if you do everything as if it were the last thing you were doing in your life, and stop being aimless, stop letting your emotions override what your mind tells you, stop being hypocritical, self-centered, irritable.”

What you can do?

Schedule every task in your calendar with the deadline. Because you should rely on the system, not willpower. Here is a thing you have a limited amount of willpower so use it wisely.
It is up to you how you want to use it whether you want to use it on a presentation that you want to make for the office or you want to waste on Instagram deciding which picture should I like.

In short
you are not lazy you just need clarity & you don’t have time, so use it wisely.

I think in this century all the word like Artificial Intelligence, Machine learning, Deep learning is so fascinating and popular that every one talking about. But I think you all are aware about that the basic of all this is Neural network and it’s base is Neurons.

No No No, I am not talking about your brain neurons , it’s artificial Neuron work like your biological neurons not both are same but we can actually relate both.

What is Neural Network ?

Neural Network is if you might have guess it is an interconnection of neurons or in modern world called Artificial neurons connected to each other and use to solve artificial problem.

First Neural Network

First Neural network discovered by two scientist named Warren McCulloch and Walter Pitts in 1943. So that’s why that neural network is called McCulloch-Pitts Neuron.

Let’s begin with A single Neural Network or so called A Preceptron .

Here We have some term in the neural network let’s crack it one by one.

Input :

Input in terms of like one hot coding which convert statements into 10100010 form.

Weights:

This are some integer value which are multiplied with the inputs.

Non-linear function : ( Activation function )

This is something we must use while programming our model because this will bound our output.

Example of Non-Linear Function :

If your problem output is between 0 and 1 means binary then you activation function will be sigmoid function.

To be continue ..

I am a programmer, Writing a program has become a difficult task if you don’t know how to control its version, before 6th month I was developing my website at that time I have only 3-month experience in programming and am bit aware of version control that’s why I mashed up my website code lot’s of time and started from a scratch lot of time. but now I know how to control the version of your project and stay away from mistakes I have made.
So, I am writing this blog about how you can also control your project versions using git and on Linux and Windows platforms.

Let’s go,

WINDOWS

For version control on windows platform, you should download git on your pc so follow the below link and download it.

Install

Download it for windows .

Now Git provide version control and Github provide you to upload your code online and share with other developer community.

Let’s Create a Github account.

GitHub · Change is constant. GitHub keeps you ahead.

Now you are ready to use Git and Github.

Let’s create a project folder and store all the content of your working project in that folder .

Let’s say name of project folder is my_project

Step 1 : Create a repository on your Github account.

Srep 2 : you will find out clone or download button click on that and copy that link it will use for further step.

Ok, Now all the work from the Github site is over.

Step 3: Open CMD and locate your project folder by cd command.

Step 4: git init

This will initialise an empty directory.

Step 5: git add .

This will add all the file which are in your project directory to local directory that will store information of which file will push to Github.

Step 6 : git commit -m “First Commit”

This command is like save command in our pc it will ensure that you are sure that you want to save all changes you have mad to push on Github

Step 7 : git remote add origin <paste link we have copied> #don’t use < > in command

This will save the info of our repository in origin veriable at which we want to push our project

Step 8 : git push -u origin master

This push your project to Github. -u is use to save info for next push.

Now you can check on Github website your project will be there.

To be continue …

Version control using Git & Github was originally published in Analytics Vidhya on Medium, where people are continuing the conversation by highlighting and responding to this story.