Lecture 3 - Software Introduction and Lecture 6 - Spatial Data Analysis

Open Source

It comes with the right to download, run, copy, alter, and redistribute the software.

Spatial Analysis

• adding value to the map

• Examining patterns, relationships, and processes within spatial data to gain insights about the world.

(Geo)spatial data

are data associated with a location information.

• Gain valuable insights

• Solve problems

• Make better decisions

Why is Spatial Analysis important?

• Where do things happen?

• Why do things happen where they happen?

• How does specific things that happens in one place affect another?

• Where should things be located?

Questions in Spatial Analysis

Combination of 2 types of information

• Location (Geographic)

• Attribute (Regular values / variables)

When is Analysis “Spatial”?

February, 2002

The QGIS project began

Gary Sherman

founder of QGIS

• Main Map

• Title

• Legend

• North Arrow & Scale bar

• Map Border and Grids

• Inset Maps

• Metadata (Data Sources)

Important Map Components

Main map

• The primary content of a map.

• Contains the main data that you want to present.

• All other components acts as the supplementary information that would help/support the main map

Title

• Should succinctly pronounce the intent of the map

• Add date/year information if needed

Legend

Contains the elements shown in map.

North Arrow

shows the orientation of the map with respect to North

Scale bar

a visual indicator of the distance and size of map features with respect to real-world size.

North Arrow and Scale Bar

They are usually placed together

Map Border and Grids

• This is where you usually indicate the coordinates on the map.

• Helps the reader identify the coordinates of the elements in the map.

• Helpful for georeferencing digital maps

Inset Map

Can either show a zoomed in portion of the main map or show the “overview” or location of the main map relative to a zoomed out view of the area.

Non-spatial analysis - location does not matter

Spatial analysis - When the location changes, the information (content) changes.

difference between non-spatial and spatial analysis

Data Sources

• Provides the agency and company names and date for each dataset used in the map. Can also contain a short description of the data.

• Information such as the creator and date, software and version used, and the agency/company of the creator can also be put in this section.

Table Joins

Combining two tables using a common unique field

P-Codes

are unique geographic identification codes, facilitating the exchange and harmonization of data and information.

• $<name>

• “<name>”

• ‘<name>‘

Some formats accepted in the field calculator.

$<name>

Functions that calculates, for example, the area, length and perimeter

“<name>”

Field names (column names) of the selected shapefile.

‘<name>‘

String values. (for numbers, no need for single quotes)