Sunday, November 12, 2017

Pandas Merge two Data frames based on common column values

Sometime back I had this "Combining multiple tabular data files together" situation at hand and I wrote about it then.

Now, there is another problem I have to solve.... It is similar to the above but not exactly the same. I will explain it below:-

The Problem

I have tow Data frames (tabular data) in which on is a subset of the other. That is to say second data frame (df2) is a subset of first data frame (df1).

Now, I need to merge them together based on a common column in the two data frames (df1 and df2) and also keep track of what row was in the the main data frame and not in the subset data frame. This is more like saying:
- Remove rows from two Data frames that have uncommon column value
- To find rows in one data frame but not in another
- Find rows which don't exist in another data frame by multiple columns

Any how you look at it, above is the general idea!


The Solution

I solved this by using the pandas merge() method with the following flags/parameters: "how='left'" and "indicator=True".



This created a Data frame with an extra column name: _merge that contains two keywords 'both' (row contain in both data frames - df1 and df2) and 'left_only' (row contain in only the left data frames - df2).



Example:-

df_all = df1.merge(df2.drop_duplicates(), on=['col1','col2'], how='left', indicator=True)
      


That is it!

Wednesday, November 1, 2017

QGIS - Label Multiple Polygons with one attribute text


QGIS Label group of polygons with single text fro the attribute field


Suppose you have a vector layer that contains polygons with the same attribute values as seen below.




You don't want to name each of the polygons because the values are the same, instead you just want one name for the whole group of polygon as seen below...



To achieve this, create a new attribute field in the to control either the label string is turned on/show or off/hide the labels by assigning the value of 1 or 0.

1 is for: On/Show Label
0 is for: Off/Hide Label


Now, after creating the attribute field, take note of the field name and go to the layers label property tab. Define and enable the field label as usual and under: Rendering >> Data Define >> Show Label, select the label control field you created above and save your changes.



All the polygons with the value of "0" will have there labels turned off/hidden only those with value of "1" will be on/showing.


Note: There are many ways to do this, the above is perfect if you want to have control over your label within QGIS map canvas.


That is it.
Thank you for reading.

Tuesday, October 24, 2017

Map of Nigeria States' Senatorial Districts

Map of Nigeria Senatorial Districts by State - You may also be interested in Maps of Various States and their Local Governments with electoral wards in Nigeria.

The Senate is the upper house of the Nigeria's bicameral legislature, the National Assembly of Nigeria. The National Assembly (popularly referred to as NASS) is the nation's highest legislature, whose power to make laws is summarized in chapter one, section four of the 1999 Nigerian Constitution. It consists of 109 senators: the 36 states are each divided in 3 senatorial districts each electing one senator; the Federal Capital Territory elects only one senator (Source: WikiPedia).

Here are the maps or visual representation for all the 36 states Senatorial Districts as defined by INEC.

Basically, it is this table provided by INEC listing the NAME OF SENATORIAL DISTRICTS in Nigeria that am representing in a more meaningful format as a map.

Wednesday, October 18, 2017

Domain-Specific Language (Geographic Markup Language - GML)

Hello there,
According to wikipedia: A domain-specific language (DSL) is a computer language specialized to a particular application domain. This is in contrast to a general-purpose language (GPL), which is broadly applicable across domains.

There is a wide variety of DSLs, some examples include:-
~ HTML
~ Logo for pencil-like drawing
~ Verilog and VHDL hardware description languages
~ MATLAB and GNU Octave for matrix programming
~ Mathematica, Maple and Maxima for symbolic mathematics
~ Specification and Description Language for reactive and distributed systems
~ spreadsheet formulas and macros
~ SQL for relational database queries
~ YACC grammars for creating parsers
~ regular expressions for specifying lexers
~ the Generic Eclipse Modeling System for creating diagramming languages
~ Csound for sound and music synthesis
~ GML - Geographic Markup Language
~ KML - Keyhole Markup Language

Thursday, October 12, 2017

Most profitable python programming skill in 2017 and beyond

Hello there,

This blog post will address the question:-
~ What Python skills are in demand in the freelance job market?
~ What Python skills are people/companies looking for?

I will share my python programming freelance experience since the beginning of this year 2017. Am also confident that this experience will last longer and remain relevant beyond 2017...

Python is one of the programming languages that is on the rise and there's really a demand for Python programmers out there. But, the question is what aspect or area of application is more profitable at the moment and in the near future?

Applications for Python
First of all, python is applicable in many areas of our day-to-day activities. Here is a high level overview of python application domain:
1) Web and Internet Development - Django, flask, Pyramid etc
2) Scientific and Numeric - SciPy, Pandas etc
3) Education - very good for teaching programming
4) Desktop GUIs (Graphical User Interfaces) - TkInter, wxWidgets, PyQt, Kivy etc
5) Software Development - SCons, Buildbot, Apache Gump etc
6) Network Administration

Read more on the official website...

Friday, October 6, 2017

Scraping StaticGen.com with Python

This is a short Python Web Scraping Tutorial

We will learn how to scrape data from this website StaticGen and have the data saved into a CSV file for further processing.

Let's get our hands dirty...

Prerequisite

You should already have at least some basic knowledge of the following:-
1- HTML and CSS
2- Python


Inspecting the site's HTML structure

Load the website on the browser and study the html structure. Use what ever tool or browser for this, I used Google Chrome browser and it looks like below:-




Ctrl+U to view source code





FireBug to view html code




Html Inspector (Ctrl+Shift+I)





As you may have noticed, the required dataset to be scrapped are arranged in rows and columns on the web page. This makes things easier since we have a consistent pattern to follow.

Wednesday, October 4, 2017

Dynamically generate HTML file from CSV data using Python

Hello there,

Assuming you have bunch of dataset in a CSV file and you want to dynamically add them on to a HTML file to upload on a web server so the someone on the other part part of the world could access and view it on the web. And you don't want to share the raw CSV file instead you want a to share a viewer friendly file such HTML, then this article is for you.

Below is the out of the script that collects data from a CSV file and populate a HTML file.



The script is as simple as below...

So, basically we just import the CSV module and read in the csv file. Then we used the open() method to create a html file in the working directory and write lines of standard html code in it.

import csv


csv_list = []
      
try:
    with open('registrant_data.csv', 'rU') as csvfile:
        readCSV = csv.reader(csvfile)
        for row in readCSV:
            csv_list.append(row)
 # ========= Create html file ================

    with open('../nametags8gen.html','w') as html8:
        html8.write('<html>')
        html8.write('<head><title>Title of the page...</title> <link rel="stylesheet" type="text/css" href="./nametags8gen.css"></link></head>')
        html8.write('<body>')
 # more algorithms to fetch csv records...

        html8.write('</html>')
        html8.write('</body>')
         

To generate new html with new contents, just update the CSV file and run the script.

That is it.
Thanks for following...

Sunday, September 24, 2017

Resize image dynamically when frame is maximized in wxPython

Hello,

I will work you through on how you will "Resize a wxStaticBitmap image dynamically when frame is maximized in wxPython

Here I have two StaticBitmap images placed side-by-side in box sizers. So, we want the size of the images to scale appropriately with the frame whenever it is been maximized.

The code....

import wx

class MyFrame2 ( wx.Frame ):

    def __init__( self, parent ):
        wx.Frame.__init__ ( self, parent, id = wx.ID_ANY, title = wx.EmptyString, pos = wx.DefaultPosition, size = wx.Size( 500,300 ), style = wx.DEFAULT_FRAME_STYLE|wx.TAB_TRAVERSAL )

        self.SetSizeHintsSz( wx.DefaultSize, wx.DefaultSize )

        bSizer11 = wx.BoxSizer( wx.HORIZONTAL )

        self.m_bitmap3 = wx.StaticBitmap( self, wx.ID_ANY, wx.Bitmap( u"img/im1.jpg", wx.BITMAP_TYPE_ANY ), wx.DefaultPosition, wx.DefaultSize, 0 )
        bSizer11.Add( self.m_bitmap3, 1, wx.ALL|wx.EXPAND, 5 )

        self.m_bitmap4 = wx.StaticBitmap( self, wx.ID_ANY, wx.Bitmap( u"img/im2.jpg", wx.BITMAP_TYPE_ANY ), wx.DefaultPosition, wx.DefaultSize, 0 )
        bSizer11.Add( self.m_bitmap4, 1, wx.ALL|wx.EXPAND, 5 )


        self.SetSizer( bSizer11 )
        self.Layout()

        self.Centre( wx.BOTH )

    def __del__( self ):
        pass

app = wx.App(0)
MyFrame2(None).Show()
app.MainLoop()

When you first launch the GUI it is like this....



Thursday, September 14, 2017

The Geo in PyCon Nigeria 2017

Hello,

I am privileged to be among the speakers at this year's python conference and the title of my talk is "Using Python for GIS and Remote Sensing Operations".

As I Geo aware individual, I was impressed with the organizers especially the guy behind the conference Venue page.



He did not only added geospatial technology on the page, but he also encouraged users to make use of the tool to make there live easier while locating the conference venue.

The web page is based on python Django web framework (Pinax/Symposion) and on these bases of python & GIS relationships, I decided to write this blog post.


What I did on the Venue Page

On the page there is a "Get Direction" tool, so i used it to get the direction from Abuja where I am coming from.



There and then I have a quick idea of where am going to and how long it will take me to reach there by road or air as seen above.

I also get the direction of my hotel (Presken Hotel) location to the venue and I observed there are two location of the hotel having similar name. However, based on the address provided I realized the correct on is with the name "Presken Hotel (Awolowo way)" and it is about 2km (5min drive) from the venue.



Thank God for Google map, everyone can at least do or interact with GIS without installing any heavy software.



You can find the presentation here: https://github.com/forum2k9/pycon-ng-2017

Thursday, August 31, 2017

Next Step after Learning the Basics of Python Programming

Hello there,

Today I want to share with you things you could do after completing the fundamentals in Python. There is always this dilemma on what NEXT after learning and completing the basic fundamentals of Python Programming.

I will attempt to solve this using my experience after being in similar situation few years ago.

Shortest Solution


The shortest answer will be that: its depend on what you want to use python for, learn related libraries in that niche. For example, if your in the Geospatial/GIS industry then go ahead and search PyPI for related libraries and learn them.


Long Solution

Now its time to program something useful to you in Python and put that theoretical knowledge to accomplishing something practical!

Pick any topic that interests you and learn the libraries related to it. There are many tutorials and documentation out for just about any library you wish to learn.

As you go through tutorial or documentation with code in it, type in all of the code and make it work. That's how I do it. That's how every programmer does it.


Find a project that interests you and try to solve it using Python. It could be in any of the following fields:-

~ Web and Internet Development
~ Scientific and Numeric
~ Education
~ Desktop GUIs
~ Software Development
~ Business Applications

Python Project Ideas

Here you will find list of practical projects to try out. 


Tuesday, August 15, 2017

Reading JSON file into Pandas DataFrame

I wanted to read in a JSON object on a python pandas dataframe for further processing. So, I tried the default pandas read JSON method: read_json('file.json'), but I got just the JSON strings returned in the dataframes's row as seen below. That isn't what I was expecting....



Fortunately for me, pandas has a solution for this in its json_normalize class that “Normalize” semi-structured JSON data into a flat table.


So, I read the JSON file and applied the "json_normalize()" class and boom my semi-structured JSON data was converted into a flat table as seen above.

That was it!

Sunday, August 6, 2017

Convert Projected coordinates (Northings/Eastings) to Geographical (Latitude/Longitude) using Python

Generally, there are two types of coordinate systems used to represent Geospatial data namely:-
1) Geographical Coordinate Systems - Polar coordinates assumes the earth is spheroid/geoid/ellipsoid/curve (Latitude/Longitude). Example: World Geodetic System (WGS) 1984. Geographic coordinate systems are based on a spheroid and utilize angular units (degrees).

2) Projected Coordinate Systems - Rectangular coordinates assumes the earth is flat (Northings/Eastings).Example: Universal Transverse Mercator (UTM) Zone 33. Projected coordinate systems are based on a plane (the spheroid projected onto a 2D surface) and utilize linear units (feet and meters)


Thursday, August 3, 2017

Download Nigeria Geo dataset for States, LGA and Ward levels

Hello,
Are you looking for a complete and comprehensive Geo dataset of Nigeria? Are you looking for complete map of Nigeria at States, LGA and Ward levels?

If yes, then you have come to the right website. Here you can download complete map of Nigeria at States, LGA and Ward levels in different file formats including image files, PDF, shapefile, CSV, GeoJSON etc.

Check out the samples below and download. If you have special request, feel free to contact me and I will convert and provide it for you asap.

Download Maps











Thanks for following...
Website: www.UmarYusuf.com
Tel: +2348039508010

Tuesday, August 1, 2017

Web Mapping - case study of Ahmadu Bello University (ABU) Zaria Main Campus (Samaru, Sabo LGA Kaduna State)

Hello there,

In today's post, I will share how to produce a Campus Web Map using free and open source tools.

I will use ABU Zaria as an example. Let's get started....

You need the vector (shapefile) map of the campus. If you don't have one, you can easily obtain a copy from the ABU GIS unit or you can digitize your copy from available google earth satellite image.

You can use any GIS software for this... here I use a free software called QGIS.


There are several free and open source methods of deploying the shapefile map to the web. Some notable method am going to discuss in few moment include:-
1) Google Map Engine
2) QGIS2Web plugin
3) Open Street Map
4) Python Folium Library

Choose any of the methods above to create your web map (there are many guide and tutorials on the internet or contact me for help).

Happy mapping.

Thursday, July 6, 2017

Setting up virtual environment (virtualenv) for python app development

When working on fairly large app in python, it is a good practice to create/setup an isolated python environment (called virtual environment - virtualenv) for development.

There are many long term reason for setting up a python's virtual environment (virtualenv) for any project you are working on. The notable once include:
1) When you have to experiment with something new.
2) When you want to use two different versions of package and compare them.
3) Virtualenv really shines when you have a number of projects, and don't want them to all share the same Python installation. For example, you could have two project with conflicting requirements.
4) Virtualenv will let you define isolated Python runtime environments without harming the root or system python installation. This comes in handy when deploying several python applications and you want to isolate the different environments. Typically this is needed when runtime dependencies differ between frameworks or libraries in different applications.

Creating a virtual environment

Step 1: Create a folder where you want to have the python virtual environment
Step 2: Open CMD or terminal window in that folder
Step 3: Enter "virtualenv name_of_folder" on the cmd/terminal

At this point, you did have a virtual environment created.


Using a virtual environment

Step 1: Open CMD or terminal window in that folder
Step 2: Enter "folder_name\Scripts\activate"
Step 3: To deactivate, simply enter "deactivate"
Step 4: To install packages enter "pip install package_name"
Step 5: To view the install packages enter "pip freeze"
Step 6: To save the install packages to file, enter "pip freeze > file_name.txt"



That is it!

Wednesday, July 5, 2017

QGIS - Restore Missing Vector menu such as: Geometry Tools

Hello,

There is a bug in the 2.16.0 Nodebo version of QGIS. This bug hides some vector processing tools (GDAL tools) found under the "Vector" menu. As already reported here... on the QGIS issues tracking page. This is caused as a result of installing "processing tools" as an external plugin.



Here is how to fix it

To fix this, go to "Plugins" menu and search for "Processing" plugin and enable it.



That is it!
Happy mapping...:)

Thursday, June 22, 2017

How to make Custom Google Map of Nigeria displaying the state capitals

In this post, I will guide you to make a customized Google map displaying the capitals of all the states in Nigeria with additional information attached to each state capital.

I will also show you how to embed it to any html web page.

Let's get started...


Requirements
1) A Google account
2) CSV file containing the states information including longitude and latitude of the state capitals



Friday, May 26, 2017

Elshayal Smart GIS and Google Earth Compatibility Error [FIXED]

There has been serious complains on this error: *** Please be sure that Elshayal Smart GIS and Google Earth are opened and running as the same, either as adminstrators or as not adminstrators. ***

With this error, there are fear that the Elshayal software is not longer useful for downloading of free images from Google Earth. That is wrong, and here I am going to share with you the solution to fix this error.


This error is largely due to the usage of non-compatible versions of Elshayal Smart GIS and Google Earth.

At the moment of writing this post, the latest compatible versions of the software are:
Elshayal Smart GIS = 17.011
Google Earth = 7.1.7.2606








You can get the latest compatible versions from the official blog here.


Are you still having troubles? Feel free to let me know. I will help you download your images, contact me by email or phone: umaryusuf49@gmail.com or +2348039508010


Thanks for following

Sunday, May 14, 2017

How to setup a Geospatial Programming Blog - Served with "Static Website Generators"

How to setup a Geo-spatial Programming portfolio Blog that scales better than the traditional blogs

Blogging is one of the most important things that any aspiring GIS programmer or Geo-data scientist should be doing on a regular basis. It can be a fantastic way to demonstrate once skills and learn topics in more depth.

There are various software for creating your Geo-Data Science blog. The software that helps you create and publish your blog is called a Content Management System (CMS), Some are free and some cost money.

One common thing with CMS is that, they heavily depend on server to deliver contents. That is a request has to be sent to a database and responses are sent in return each time a use perform an action on the blog. This can be time consuming and over killing for a static geo-data content blog.

As a Geospatial programmer, if you really want to setup a GIS scripting oriented blog that scales very well. Then look beyond server centric CMS blog engines such as Blogger, Joomla, WordPress, Drupal etc. Instead choose a "Static Website Generators" that gives room for increasing both speed and uptime, and managing static sites with version control systems like Git means the process of creating and updating sites is highly efficient.

Static site generators allow a user to create HTML files by writing in a markup language and coding template files. A static website generator combines a markup language, such as Markdown or reStructuredText, with a templating engine such as Jinja, to produce HTML files.



Open-Source Static Site Generators

There are several of them, a comprehensive list is available at: www.staticgen.com

Since this blog is about python Programming, I will list those static site generators written in Python programming language below. Later on, I will cover how to create a blog using Python, how to create posts using Jupyter notebook, and how to deploy the blog live using Github Pages.


List of Python powered static site generators

1. Pelican - www.blog.getpelican.com/
2. MkDocs - www.mkdocs.org/
3. Cactus - www.github.com/koenbok/Cactus/
4. Lektor - www.getlektor.com/
5. Hyde - www.hyde.github.io/
6. Nikola - www.getnikola.com
7. Sphinx - www.sphinx-doc.org/
8. Frozen-Flask - www.pythonhosted.org/Frozen-Flask/
9. Blogofile - www.blogofile.com
10. Acrylamid - www.posativ.org/acrylamid/
11. Tinkerer - www.tinkerer.me
12. Tags - www.tags.brace.io/
13. staticjinja - www.staticjinja.readthedocs.org/en/latest/
14. Urubu - www.urubu.jandecaluwe.com
15. Grow - www.grow.io/
16. Tarbell - www.tarbell.io
17. wok - www.wok.mythmon.com/
18. Statik - www.getstatik.com/
19. QPage - www.qpage.ir
20. drupan - www.github.com/fallenhitokiri/drupan
21. Prosopopee - www.github.com/Psycojoker/prosopopee
22. PyKwiki - www.pykwiki.nullism.com
23. PieCrust2 - www.bolt80.com/piecrust
24. Poole - www.bitbucket.org/obensonne/poole/
25. Pagegen - www.pagegen.phnd.net
26. django-distill - www.github.com/mgrp/django-distill
27. Halwa - www.github.com/mhlakhani/halwa
28. Blended - www.jmroper.com/blended/
29. Blo - www.github.com/savuir/blo
30. YASBE - www.github.com/underr/yasbe
31. Bang - www.github.com/squdle/Bang
32. Rocadocs - www.rocadocs.com
33. BootDown - www.project.geekweaver.com/



Creating a Geo-Data Science portfolio blog will improved your career more than anything else and land you your dream job while doing the work you love.


Thanks for following.

Saturday, April 29, 2017

How do I do that in ArcGIS and QGIS - Learn both ArcGIS and QGIS Simultaneously

According to WikiPedia, there are two major categorization of Desktop GIS software namely:-
1- Commercial or Proprietary GIS software
2- Open Source GIS software

Over the years, the leading Desktop GIS software for the two categories above are ESRI ArcGIS and QGIS.

In this blog post, I will show you how to do basic GIS operations in both ArcGIS and QGIS. If you are interested in knowing the difference between the two software, here are some interesting articles on the internet I have found:-
a) QGIS v ArcGIS
b) 27 Differences Between ArcGIS and QGIS – The Most Epic GIS Software Battle in GIS History
c) ArcGIS vs QGIS – 10 Most Important Differences Between ArcGIS and QGIS
d) How does ESRI ArcGIS (proprietary) compare with Quantum GIS (QGIS) (open source)?
e) GIS lounge - QGIS versus ArcGIS

So, this post isn't about which is the best GIS software, instead it will address common questions in the form of "How do I do that in ArcGIS and QGIS". I will go over how you can perform some of the very basic GIS tasks in both ArcGIS and QGIS, and you will decide at the end which software approach is easier and better for you.

Along the way, you will be learning both ArcGIS and QGIS software simultaneously.

Lets get started...




Sunday, April 23, 2017

Installing wxPython on Python 3.x

Few years ago I wrote this blog post on "How to install wxPython (Phoenix) on Python 3.x". Since then, a lot has happened including the release of "wxPython 4.0.0a1"


So, today I decided to install the latest alfa release on my python 3 anaconda setup. I went to wx PyPi url downloaded the wheel file locally and ran: pip install wheel_file_name to install successfully as seen below.



I tested the installation, by importing wx and it work perfectly.



Congrats WX is now officially on python 3

Monday, April 10, 2017

Cleaning big data CSV file with Python

Hello there,

I know I can open a CSV file in a spreadsheet software like MS Excel or a text editor like NotePad++ and edit/clean its contents (by removing unwanted contents).

In a situation where by the CSV file is very big (big data - it contains millions of rows and columns), if you try to open such file in a spreadsheet software or a text editor there is possibility of memory error from the software you are using as seen in the image below. This excel error says: "File not loaded completely", the file appeared to be beyond MS excel capabilities.



This is where using a data oriented language such as Python comes in handy. Python pandas module can efficiently load/open and process such heavy duty big data files without much difficulties.

Saturday, April 1, 2017

Windows PostgreSQL installation Error - Unable to write inside TEMP environment variable path

Here is the solution to the "PostgreSQL installation Error - Unable to write inside TEMP environment variable path" on windows PC.

I downloaded the latest version of PgAdmin4 for PostgreSQL 9.6 from EnterpriseBD. When I tried to install it, I got this error massage: There has been an error, Unable to write inside TEMP environment variable path.




Solution to the Error


Now, to solve this error on your windows machine proceed as follow:-
1- Locate your windows sytem32 folder at: C:\Windows\System32



2- Inside the folder, find regedt32.exe file and run/open it


3- Navigate to this folder: HKEY_CURRENT_USER >> Software >> Microsoft >> Windows Script Host >> Settings



4- Right click on the "Enable" icon and select "Modify"



5- Change"Value Data" from 0 to 1 and click on "OK"



6- Close the Registry Editor and you are done.



Thanks for following.

Python break, continue and pass within Try... Except block

Hello there,

When using loops in python, there are situations when an external factor may influence the way your program runs.  You may want your program to exit a loop completely, skip part of a loop before continuing, or ignore that external factor. You can do these actions with break, continue, and pass statements respectively.

The "pass" statement is a no-operation (meaning that it doesn't do anything). The program just continues to the next statement, which is why you get an error.

The "break" statement exits the loops and continues running from the next statement immediately after the loop. In this case, there are no more statements, which is why your program terminates.

The "continue" statement restarts the loop but with the next item.

Sample Code

for letter in 'Python':
   if letter == 'h':
      break # continue pass
   print ('Current Letter :', letter)


Testing the above code for: break, continue and pass will yield different results as seen below:-





If we introduce a "Try ... Except" block and intentionally call an error, only pass will print the error statement at the end of the block statement.




Thanks for reading.

Sunday, March 26, 2017

Assigning single attribute to multi geometric features in QGIS

There are situations when you will want as many as possible geometric features within a shapefile layer to share the same attribute information within the attribute table.

This kind of scenario is commonly seen when representing Islands. The attribute data is the same, but the geometric representation of the Islands (in polygon) will be separated from each other to give way too water bodies.

As an example, am going to use a Nigerian state the has Islands (Bayelsa state). So, to digitize Bayelsa into wards polygons we have to deal with Islands. And here I have three polygons representing the same ward with ward_code 12 as seen below.

So, the task here is to merge or combine these same attributes into one and all the three polygons will share that same attribute information/row.



In QGIS, to make multiple polygons share the same attribute proceed like thus:-
1) First digitize the Islands polygons and assign the same attributes as usual
2) Go to Vector Menu >> Geometry Tools >> Singleparts to Multiparts


3) The next window will prompt you for the input layer (from a drop-down list) and the Unique ID field (Ward_Code) and you can specify an output file name. Select the appropriate information and click on run.


4) You should now have multi polygons sharing one row of your attribute table


Alternative method


Alternatively, you could use the "Merge Selected Features" command available in the Advanced Digitizing Toolbar as seen below:-


Select the polygons you want to merge there attributes and click on "Merge Selected Features" within the "Advanced Digitizing Toolbar", configure the attributes accordingly and click on "Ok".


That is it.
Thanks for following.