Monday, January 14, 2019

Python Programming for GIS Data Processing in QGIS

Python is a general purpose programming language that has a strong presence in the GIS industry as many house hold software such as ArcGIS and QGIS do expose their interfaces through python scripting.

Broadly speaking, python can be used for any of the following:-
1~ Scripting and Automation
2~ Web Development
3~ Data Science — including Machine Learning, Deep Learning, Data Analysis, and Data Visualization
4~ Embedded Applications - Hardware Programming
5~ Gaming
6~ Desktop Applications
7~ Network Programming

Here our focus will be to use python to automate GIS processes via well packaged video series as seen below. Python is excellent tool for doing GIS data wrangling, data manipulation and analysis processes. That is exactly what I set out to teach you in this video series.... By the end of the tutorial, you should be able to use python to:-

  • Extend the capabilities of mapping applications
  • Build a GIS workflow
  • Automate redundant tasks
  • Integrate maps or spatial data into other applications
  • Build your own applications

Let's get our hand dirty manipulating GIS data with python starting with the basics off cause 😊.

Video 1: Getting Started Setting up working environment





Video 2: Writing and executing code





Video 3: How to Install Third-party Python Modules in QGIS 3.x





Video 4: Python Implementations, Comment, Variable, Interactive Help





Video 5: Python Data Types - Part 1





Video 6: Python Data Types - Part 2




Video 7: Python Data Types - Part 3


Coming soon...


Saturday, January 12, 2019

How to Prepare A Site Plan

Before we see "How to a Site Plan can be Prepared", here is a little background to what it is.

Who is a Land Surveyor?
A land surveyor is person who is trained and licensed by a regulatory body to practice legal survey profession in a state. This person will be under the supervision of the state's surveyor general or the director/commissioner of surveys for that state.

One important document produced by land surveyors is the site plan (also called survey plan or professional survey or boundary survey or lot description or final survey or parcel demarcation etc).


What is a Site Plan?
A Site Plan is a graphical description of a parcel of land that is attached to the application of Right of Occupancy (RofO) or Certificate of Occupancy (CofO) over a landed property. It is a necessary legal document required by the authority to approve the development of a land parcel. It is a document that measures the boundary of a parcel of land. It gives an accurate measurement, description of the piece of land.


Information to be Shown on a Site Plan
A professional site plan drawn to scale should show the entire property (including all property lines) with the existing and proposed structures. Other information that must be shown include:
~ the name of the owner of the land surveyed
~ the address or description
~ the size and the drawn-out portion as mapped out on the survey plan document
~ the beacon numbers
~ the name of the Surveyor who drew up the survey plan
~ the date it was drawn and a stamp showing that the land is either free from government acquisition or not
~ the directional arrow (aka North Arrow)
~ the Scale at which the plan was drawn
~ the coordinates system used
~ the reference control beacons used

Why is a Site Plan Required?
The primary reason why a site plan is required is to get what is known as a "Land Information". Before a transaction is consummated over a plot of land, it is always advisable to prepare the site plan presented for the land to basically find out whether it falls under government acquisition or not and as well authenticate the claim of ownership to the land.
In the case of a new construction, building additions, substantial accessory structures, and parking must be submitted on a professional stamped survey. Land authorities will make the final determination whether your project met the requirements to be implemented on that land.

Can I Draw the Site Plan Myself?
Yes, if you have the skills to do it. However, if the purpose of the plan is for legal documentation a registered surveyor most endorses your work to be considered by any authority.

How to Prepare A Site Plan

You don’t have to be a genius to prepare a site plan, but you do have to be able to work with the tools that helps you collect data from site and draw them on a paper.

Basically, there are two phases to producing a site plan namely:-

Phase 1: Site work
Here is where the surveyor goes to the field for the purpose of data collection. Depending on the purpose and the accuracy of the survey plan, different kind of instruments are used for the site data collection. These instruments include:-
a) Chain instrument
b) Compass
c) Theodolite
d) Total station
e) GPS

Whatever the instrument used, you will collect data such as distance, bearings and coordinates that will be used to draw the survey plan in the next phase.

Phase 2: Office Work
This is where you do the actual drawing of the survey plan. There are different kind of instruments used for plotting/charting survey plan, however the most commonly use software is the AutoCAD drafting software.

Learn to draw/plot survey plans using a FREE software similar to AutoCAD from here.

Thank you for reading.