In this post, I will tell you about Python and basicly Numpy. Python is a programming language. It’s popular in nowadays, because simple and useful.

Numpy is a Python library. It’s have functions about math operations and vectors. Useful because speedy about math operations. Let’s look in Numpy functions a little more.

For using Numpy, we have to import it. Importing is simple, just write import numpy as np. np section is optional. Generally, it’s functions about arrays, vectors. So we will create an array and start.

Creating arrays are simple like always. We just define a variable and use…


In this article, we’ll begin visualization with Python. I’m still learning, continue a course, so this material is about course. Let’s start!

I will use Kaggle and a dataset in Kaggle. You can go to my Kaggle profile and examine my notebooks:

https://www.kaggle.com/serapbaysal61

Of course you don’t have to use Kaggle, you can install dataset and use it on your pc. The dataset’s link is here too:

https://www.kaggle.com/kwullum/fatal-police-shootings-in-the-us

Firstly, we’ll import libraries that we’ll use:

import numpy as np 
import pandas as pd
import seaborn as sns
import matplotlib.pyplot as plt
from collections import Counter

In this dataset, we have…


In this article, we’ll continue to SignUp application. In this part, I’ll write about forgot password, sending email with nodemailer and reset password. If you ready, let’s begin!

First of all, in previous part I used mailgun, not nodemailer. But when I searched about sending email methods, I see nodemailer and wanna use it just for diffrence.

For reset password, we need a String variable in User model. I create a Date variable too, but I don’t use it so you can pass it. The String variable named resetPasswordToken. We need package called crypto, we’ll require it in top.

In…


In this article I wrote about how to verificate an email in SignUp application. For this, I used my old codes, Postman and of course MongoDB Compass. If you want to learn about how to write old codes, you can reach following links:

Part 1: https://serapbaysal.medium.com/signup-login-application-with-nodejs-express-and-mongodb-658498e580cf

Part 2: https://serapbaysal.medium.com/logout-with-nodejs-express-and-mongodb-9b73e8b01137

Now, if you ready, we can start!

First of all, we need mailgun. We go to mailgun website and add an account. It’s free for signup aplication so you can it for free. After that, we’ll write npm install mailgun-js in terminal and install package. We’ll go to controllers/auth.js …


In previous articles, I wrote abot how to create SignUp and Login application with NodeJs, Express and MongoDB. The link is here, if you want remember the article, you can read:

https://serapbaysal.medium.com/signup-login-application-with-nodejs-express-and-mongodb-658498e580cf

In this artical I will create a logout application, with my old codes. Let’s start!

First of all, we wants to protect some operations in application, like reaching profile. For this we will create a middleware called auth.js and write a function named protect.

In this file, firstly we require jsonwebtoken, ErrorResponse and User model. With exports.protect = async (req, res, next) => {}, we’ll begin.

We go…


We learned Python’s libraries called Numpy and Pandas. Now, we will use them on a real data. For this, we need a Kaggle account. Or if you want, just install data sets and use them in local computer.

Let’s start!

What Is Kaggle?

Kaggle is an online community of data scientist and machine learning practitioners. Users can find and publish data sets, explore and build models, practice about machine learning, join competitions…

In this article, I use a data set in Kaggle. Kaggle has a compiler on itself, so I will use it.

First of all, we need introduction about…


In this article, I will write about how to creating a SignUp Project with NodeJs and MongoDB. Let’s start.

I will use Visual Studio Code as compiler. In this project we need a package.json file. For this, in terminal, we’ll write

npm init

command. After that command, to fill our package.json, it want some informations. I leave it like that and just push Enter. I just need to change in package.json file, “main”: “index.js” file to “server.js”.

Than with npm install Express dotenv command will build Express and dotenv modules. So this commands create node_modules and package-lock.json files.

After that…


After Numpy library, I will explain what Pandas library is, why useful and why we should use this.

Pandas library created for studying data frames. So, what is data frames? Data frames are excel files, this files has datas.

In Pandas, transition from file to file (.csv or .txt files) is easy. Also examining and saving files easy too.

Files can have missing values. If you studying with real world datas, you can see that. But that’s not problem on Pandas.

Pandas usually using with time series too. …

Serap Baysal

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