Some time ago, probably yesterday or the day before, I had to filter a pandas dataframe and somehow it did not come intuitively into my mind how to do it. As I did not have an article about it, I…
Category: Python
Python code examples
Python – Just a bit about datetime and timedelta
Ok, dates in VBA and Excel are somehow complicated, because of some “feature” that Microsoft Excel has introduced, due to compatibility issues. I have already wrote a few articles about these here, and separate one about what day is Friday…
Python – Init a class with a default list property correctly
Sometimes, (but only sometimes) we think that writing too much code is useless and writing less code in python is more readable and performs faster. While in the general case this is true, this article is simply going to show…
Python – Reading and writing to the console
Reading from the console and writing to it is a piece of cake in python. These two functions do it for you perfectly:
|
1 2 |
a = input() print(a) |
Then why am I writing a whole article about it? Well, there is something fancy, if…
Python – Enumerate Lists in a Loop
Plenty of times, when you are looping with a for-each loop in python, you somehow realize that you need a counter. Then you most probably write something ugly like this one:
|
1 2 3 4 |
a = 0 for count_value in my_odd_squares: a = a + 1 print(f'({a}, {count_value})') |
Why is this ugly? Mainly because the next…
Python – Write a DataFrame or List to multiple tabs in Excel
The idea of the article is to provide a Python code that does the following: Takes a list or DataFrame; Splits it into quite a few smaller parts; Writes each one on a separate Excel worksheet; Pretty much like this:…
Python – Plotting a circle with matplotlib
Plotting a circle with matplotlib library in python is an interesting task. If you google it, you will find quite good answers, but anyway, I am here because I want to summarize my point of view. Pretty much, the idea…
Python – dictionary to CSV
Dictionary to a CSV file is probably a good question, if you are hiring a VBA developer. For a python person it should be a trivial one, as this one should not be even a tough search in Google. Anyway,…
How to get redirect url using Excel VBA or Python
Getting some tiny URL, that redirects you to somewhere else might be dangerous. There are a lot of people, that would never ever click on bit.ly/something or goo.gl/something, just because they do not know where the redirect is going to…
Python – Find All Substrings Between Two Character Pairs with RegEx
Sometimes you need to do what you need to do – use Regular Expressions for a trivial task. Now, imagine that you have some big text and you need to extract all substrings from the text between two specific words…
Python – Parsing PDFs with Tika
Reading from a pdf is actually quite an easy task with Python. If the PDF is of course “readable”, e.g. made from a word processor. The first thing to do is to install Tika and Java:
|
1 2 3 |
pip install tika <em>conda install</em> -c conda-forge <em>tika # as alternative</em> java --version #this one checks the installed java version in the command prompt |
Having this, the…
Python – Ordered Dictionary and Heap Queue
After writing about Default Dictionary in Python some time ago, now it is time to take a look at the ordered dictionary and the heap queue as these are built-in structures, coming out of the box. And they are fancy.…
Python – Read and Write to Excel ActiveX Textbox
Reading and writing to an Excel ActiveX textbox with Python can be fun. If you really do not have anything better to do. Anyway, if this is your current task, you are on the correct place to see how it…
Python – How to fill Excel cell with image, using python
If you have ever dreamed that it will be possible to fill out an Excel cell with a picture, using Python, then you should probably reevaluate your dreams. Seriously, who dreams of something like that? Without further dreaming, the code…
Python – Logging in Python. Formatting with Black
Logging in Python is beautifully implemented with the logging library – https://docs.python.org/3/howto/logging.html It simply does anything you need and you do not need to write something yourself, like I did some time ago here in my VBA Boilerplate. So, if…
Python – Multisets – A class to count the elements of a set
Ok, so you probably have heard about set in Python – it is a collection with non-repeatable elements – as if you are a stamp collector and you need to collect only the unique stamps into your album. However, in…
Python – Writing a Logger in Python with a decorator
Functions in Python are objects. If this is the first time you read this sentence, then you will not get a lot from this article, but it will show you, that there is quite a lot to learn about Python.…
Python – DefaultDict Object. Or how to avoid the Key Error.
Have you seen the error below?
|
1 2 3 4 5 6 |
Traceback (most recent call last): File "C:/Users/foo/PycharmProjects/pythonProject3/main.py", line 29, in <module> main() File "C:/Users/foo/PycharmProjects/pythonProject3/main.py", line 19, in main a['foo'] += 5 KeyError: 'foo' |
Of course you have. And you know, that it is because you have written something extremely unwise like this:
|
1 2 |
a = dict() a['foo'] += 5 |
Yeah. You cannot increment the value of a non-existent key. Unless… Unless you…
VBA and Python – Intersection of dictionaries
Intersection of dictionary (or of any two lists) is a list with elements, that are present in both other lists. Thus, if we have the following 3 dictionaries in Python:
|
1 2 3 |
dict_a = dict([('aa', 4139), ('bb', 4127), ('cc', 4098)]) dict_b = dict(aa=4139, bb=4127, ee=4098) dict_c = {'aa':12, 'bb':13, 'dd':23} |
Then, an intersection of their keys will contain only…
Python – Class Variable vs Instance Variables
Class variables vs instance variables could seem a bit strange, if you have no OOP experience, but after a few thausand lines of code they become logical. So, in around two days of programming you will be getting it intuitively…
Python – Difference between __str__ and __repr__
__repr__ and __str__ dunders are quite similar in Python. If you need a quick summary of these 2, then these 3 points will be enough: __repr__ dunder presents the class object, whenever it is called by the terminal __str__ dunder…
Json.dump vs json.dumps in Python
The difference between json.dump and json.dumps is actually quite visible: dump() – dumps into a file or StringIO dumps() – dumps a string, that could be printed Still, I am going to give a few example with these, as the…
Python – Iterators
One of the benefits of having your own blog and not following any schedule for subjects to write about is that you may write for whatever you feel like, whenever you feel like. So, Iterations in Python is the subject…
Django – CRUD application with Python
Making a CRUD application with Python is actually one of the basic thing a Python Developer should be able to do. Although some may argue it is extremely basic – it is not. Requirements The basic requirements for this one,…
Django – Making a simple web app with 4 links
The idea of the article is to show how to make a simple Django App, with 4 links, each of which navigates to a specific page. The whole code of the “app” is in GitHub, here: https://github.com/Vitosh/Python_personal/tree/master/JustProject. In general, these are…
Python – Exception handling
Exception handling in python is actually quite an interesting topic. In general, the exceptions in programming could be of three types: syntactic errors – these would be noticed by your IDE or by the interpretor, thus you do not need…
Using API calls with VBA and Python to Read and Write to a Database
Using API calls with VBA and Python to write a database is actually a pretty decent architecture. Here, I would like to say that “It takes the best of the both worlds”, but the truth is that it takes the…
Python – Virtual Environment
This is a short step-by-step introduction on how to build virtual environment in Python and how to use it. Virtual envirnments keep dependencies, required by the specific project separated. Thus, it is the “clean and clear” place of the project,…
Python – Django Girls – Introduction to Django – Video
Months ago, I was planning to take part in the #RailGirls event in Sofia, and I was even a partner in the event. Anyway, as it was postponed up to somewhere in the future, I have decided to go through…
Top
Python – Docstring – Help and Comments
Docstrings in Python are actually quite simple – the are 3 times this """ and the code between opening and closing them can be formatted in any possible way. The reason I have decided to dedicate a whole article to…