Following the Microsoft tutorial for building a .Net Standard library with Visual Basic from here, I have decided to make a video for .Net Standard library with C#. Pretty much, it is one and the same. The library contains one…
Author: Vitosh
Writing data from text file to Excel cells
There are quite a few methods for writing data from a text file to Excel. The main are the following: Through a Query Table Through opening the text file and Reading and writing line by line Reading the text file,…
Tagged with: Data Transfer, from text file, LoopThroughLines, QueryTables.Add, to excel cells, Writing data
Python – UnitTests in Jupyter Notebook
Unit testing is the “sweet” part of the programming – once you have tested “all the things”, you feel that the code you have submitted somewhere is actually valid and somehow it works. Furthermore, it allows you to nicely brag…
Book Review – Stephen Wolfram – Adventures of Computational Explorer
Some time ago, I have received the book of Stephen Wolfram – Adventures of Computational Explorer for a review. Stephen is the guy behind WolframAlpha – https://www.wolframalpha.com/, a PhD in physics before his 21. birthday, considered a prodigy by some…
VBA – Extracting financial data from a website in table format
Although there are plenty of other tools for extracting data from a website (take a look at Beautiful Soup), VBA is somehow good, because … well, because it is somehow challenging to do it every time. Yesterday, I answered a…
Tagged with: Data scraping, from cell, from internet, reading data, reading from table, remove empty elements from array, VBA
Python – Statsmodels Example – Video
Statsmodels is a nice statistics library in Python, which eases the data processing and analysis with Python. The library is available here – statsmodels.org and on its official web site the installation guide is always up to date. In the…
Excel – How to build magic square with VBA, following Python Mod Mathematics
Some 4 years ago I wrote an article for calculating magic square with python. What the article did was actually checking whether the square is magic, and not calculating a new one. This one is going to show how these…
Python – Plotting DataFrame and Working with Pandas – Video
Working with Pandas is like working with Excel on steroids – it can really do a lot of things fast, but somehow doing the easy things get complicated. In this video and article tutorial I am presenting loading data to…
Python – Platforms Jumping – CodeForces
Greedy algorithm is described as an algorithm that follows the problem-solving heuristic of making the locally optimal choice at each stage with the intent of finding a global optimum. Thus, it is always interesting to find a problem, which can…
Python Slice Notation
Python Slice Notation is somehow easy and tough in the same way. Lately, I was doing some competitive programming with Python and I have decided to write a summary of the slice notation, thus there is always a place for…
Python – Binary String Minimizing Problem – CodeForces
Codeforces has introduced a third division in their competitions. Initially I though this is the place to go for “easy” stuff, as far as some of the 2nd division problems require some advanced algorithms, like combinations of graphs and months…
Find all list (li) elements in a special position of a web site
So, my idea was to obtain all the elements, tagged with “li” from here – vitoshacademy.com/all, using BeautifulSoup4 and Python. Initially, I thought about running a simple soup.findAll("li") , but it also added the text from the menus, which were…
Scraping a web site up to the N-th level with Python
Scraping data from a web site has always been a pleasure with Python. If you come from the VBA world, the BeautifulSoup4 is indeed beautiful! I have been scraping a web site with python before, but now as I have…
Dynamic dropdown list in Excel VBA with variables
Dropdown lists in Excel usually are built from a range or from a variable list. Dropdown list from Excel Range Thus, building a dynamic dropdown list may include building a dynamic range, with undeclared end. Thus, let’s imagine that the…
Prime numbers matrix and coloring with Python and xlsxwriter
About 4 years ago, I wrote an article about prime numbers in Excel and their visualisation with VBA – vba-function-in-excel-to-check-prime-numbers. Pretty much, it displays the prime numbers in a 10 x N matrix, starting from 1 and finishing at N:…
Tagged with: align, bg_color, center, Excel, first column and first row of Excel is with index 0, font_color, format, matrix, prime numbers, Python, xlsxwriter
Scraping web site and writing its links to a database with Python
Scraping a web site with BeautifulSoup 4 and Python is a walk in the park, if you have scraped a web site with VBA before. Still, there are a few tricks, that should be taken into account. Trick #1 –…
Adding data to SqlLite3 database with Python
After reading the database to python from the previous post here, it is time to do the ADD data to the database. Our database is created like this:
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CREATE TABLE "drummers" ( "Id" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, "Name" TEXT, "Band" TEXT ) |
The database has autoincremented primary key, thus we do not need…
Connecting SqlLite3 database to Python and Reading it
Connecting SqlLite3 database to a Python file is actually 1 line of code: conn = sqlite3.connect(r"C:\Users\database.db") I have used a database from sqllitetutorial.net, which was rather neat. Then DB Browser for SQLLite a LEFT JOIN was implemented, in order to unite the…
Adding data to SqlLite3 database, but only one value with Python
Life is hard, when you are learning Python and you see things that are making no sense the way they run. After writing about adding data to SqlLite3 with Python, today I have tried to do the same, but for…
Find all HTML tags in a web page and print them from a sorted dictionary
Finding all HTML tags from a web page and recording these to a dictionary is magically easy task with Python (if you compare it with #VBA), when Beautiful Soup 4 is used. soup.find_all(True) loops through the tags and a simple…
Write Formulas in Excel through Python XlsWriter
Writing formulas with Excel with Python is a technique, that needs some practice, actually. Although XlsWriter has some good documentaion, not a lot is covered on the point, that concerns creating a file with a formula in it. First and…
Writing to a text file in Python from a variable, ignoring encoding problems
Writing to a file in Python is usually a simple 2-liner, which is easy to be written:
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with io.open("soup.txt", "w") as file: file.write(soup_written) |
However, problems with the encoding may cause some research needed. Concerning the encoding this is a great article from the creator of…
Show all links from a website with Python and BeautifulSoup
Showing all links from a website with Python and BeautifulSoup is actually 6 lines of code – 2 to define the used libraries and 4 to do the job:
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import urllib.request from bs4 import BeautifulSoup resp = urllib.request.urlopen("https://www.vitoshacademy.com") soup = BeautifulSoup(resp, from_encoding=resp.info().get_param('charset')) for link in soup.find_all('a', href=True): print(link['href']) |
In general, BeautifulSoup comes out of the box with beautiful…
Python – The birthday paradox algorithm
The birthday paradox is an interesting problem, mainly because of its somehow “unexpected” results. The problem usually is stated as the following: What is the minimum number of people in a room, in order to have a probability higher than…
VBA – How to implement workbook events in Excel – GIF
The Excel Workbook object is a part of the Workbooks collection. The events are the code, which is “activated” or “triggered”, once a specific event happens. These events are different and could be unlimited, but there are a few built-in Workbook…
Sets in Python – Differece, Symetric Difference, Union, Intersection
After writing the article scraping a web site up to the N-th level with Python, I have decided to summarize what could be achieved with Set() in this language. Pretty much, sets can be described as lists with a few…
Numpy and Pandas – Small introduction with Jupyter Notebook
Last week I was participating at the Python and ML Summit in Berlin. One of the most interesting lectures, on which I participated, was a workshop by, named “Reading all yourself was yesterday – How to turn large amounts of…
Python and MachineLearning Summit in Berlin – Summary
This Monday and Tuesday (14. – 15. October 2019) I was in Berlin, participating at the #Python and #ML Summit. Actually, #Berlin is a nice city, one of my favourites in Germany, thus if you are not from there, only…
Competitive Programming – Bus Stops Problem – Video
In competitive programming, following the ICPC rules, one of the best strategies is to scan the problems given to your team and to start with the easiest ones. The easiest ones are not always the first problems and sometimes these…
VBA – How to avoid naming variables with non-latin alphabet characters (special letters)
Writing code in the local language is actually taught by about 100% of the German VBA books, which I have read. Which is “kind of ok”, if the VBA code only works on German computers. However, if this is not…
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