Spatial and non spatial data in gis pdf notes
File Name: spatial and non spatial data in gis notes.zip
- Spatial Data Characteristics
- Spatial Data Characteristics
- Information Cartography: Using GIS for Visualizing Non-Spatial Data
- 3 types of data
A Geographic Information System is a multi-component environment used to create, manage, visualize and analyze data and its spatial counterpart. If, for example, we are interested in identifying the ten African countries with the highest conflict index scores for the period, a simple table listing those scores by country is all that is needed.
No matter what your interests are or what field you work in, spatial data is always being considered whether you know it or not. Spatial data can exist in a variety of formats and contains more than just location specific information. To properly understand and learn more about spatial data, there are a few key terms that will help you become more fluent in the language of spatial data.
Spatial Data Characteristics
No matter what your interests are or what field you work in, spatial data is always being considered whether you know it or not. Spatial data can exist in a variety of formats and contains more than just location specific information. To properly understand and learn more about spatial data, there are a few key terms that will help you become more fluent in the language of spatial data. Vector data is best described as graphical representations of the real world. There are three main types of vector data: points, lines, and polygons.
Connecting points create lines, and connecting lines that create an enclosed area create polygons. Vector data and the file format known as shapefiles. Raster data is data that is presented in a grid of pixels. Each pixel within a raster has a value, whether it be a colour or unit of measurement, to communicate information about the element in question.
Rasters typically refer to imagery. However, in the spatial world, this may specifically refer to orthoimagery which are photos taken from satellites or other aerial devices. Raster data quality varies depending on resolution and your task at hand. Spatial data contains more information than just a location on the surface of the Earth. Any additional information, or non-spatial data, that describes a feature is referred to as an attribute. Spatial data can have any amount of additional attributes accompanying information about the location.
Each of the buildings, in addition to their location, may have additional attributes such as the type of use housing, business, government, etc. To identify exact locations on the surface of the Earth, a geographic coordinate system is used. Normally, an x and y-axis are used in mathematical systems, but in geography, the axes are referred to as lines of latitude horizontal lines that run east-west and longitude vertical lines that run north-south.
Georeferencing and geocoding are different but similar processes since both involve fitting data to the appropriate coordinates of the real world. The data used in geocoding are addresses and location descriptors city, country, etc. Each of these locations is given the exact coordinates of reference for that location on the surface of the Earth. The most common way that spatial data is processed and analyzed is using a GIS, or, geographic information system. These are programs or a combination of programs that work together to help users make sense of their spatial data.
This includes management, manipulation and customization, analysis, and creating visual displays. A user will typically use multiple spatial datasets at one time and compare them or combine them with one another. Each spatial dataset may be referred to as a layer.
If you were using GIS for a municipality project, you might have vector data like street data lines , neighbourhood boundary data polygons , and high school locations points. Each dataset would exist as its own layer in your GIS. Placement of layers is important for visual purposes as it will help you understand the various types of data and present your findings in an easily understandable way. In this case, you would want to make sure that high school points and street lines are layers above neighbourhood boundaries.
Otherwise, you would not be able to see them. The field and study of GIS extends much further than digital mapping and cartography. It consists of a variety of categories including spatial analysis, remote sensing, and geovisualization.
In these GIS fields, the spatial data becomes much more complex and difficult to use. In addition to raster and vector data, there is also LiDAR data also known as point clouds and 3D data.
LiDAR data is data that is collected via satellites, drones, or other aerial devices. Maps are a common practice of presenting spatial data as they can easily communicate complex topics. They can help validate or provide evidence for decision making, teach others about historical events in an area, or help provide an understanding of natural and human-made phenomena. When creating visuals, graphics, or maps with spatial data, there are a variety of geographic elements to consider.
One of the most important and coincidentally most problematic elements is projection. No projection is perfect and depending on your projection you may be sacrificing accuracy in shape, area, distance, or direction. Maps can also be used to present what are typically non-visual elements of society. For example, the occurrence of certain events, income level, any demographic descriptor, or relationships like the number of heat strokes in an area compared to temperature.
A simple display method is a classification map, also known as a choropleth map. Choropleth maps easily communicate differences, consistencies, or patterns across space. Classified areas in a choropleth map will have distinct boundaries whereas heat maps, which demonstrate the concentration or density of a phenomenon, have indistinct boundaries. Classification or heat maps can be used as the bottom layer for other variables like car accidents or crime to highlight certain trends and potential correlations.
As it is with any data, to truly make sense of spatial data and understand what it is saying you must perform some level of statistical analysis. These processes will help you uncover answers and lead you to make better decisions for your organization. The major difference between spatial data and all other types of data when it comes to statistical analysis is the need to account for factors like elevation, distance, and area in your analytical process. While needing to account for additional variables about a location may be intimidating, many spatial statistic processes are quite similar to basic statistical methods.
For example, interpolation can help you estimate or predict the value of a sample, and spatial interpolation can help you estimate or predict the value of a variable in a sample location. Similarly, spatial autocorrelation measures the degree of similarity between sample locations just like typical autocorrelation is done. There are many architectural, engineering, and construction AEC companies that use CAD computer-aided design and BIM building information model data in their day-to-day activities.
While CAD and BIM may not necessarily be thought of as traditional spatial data, they and other AEC formats also need to consider many spatial elements to understand their work. Mapping is also no longer limited to the natural world. Indoor mapping and wayfinding are becoming much more popular especially in large buildings and institutions like malls, arenas, hospitals, and campuses.
This field of study is new but shows no signs of stopping. Everyone has a smartphone these days and uses it to help them navigate the natural world, so why not help people navigate the indoors too? While there are many tools and software that can help you make use of spatial data, FME is the software of choice for those that need to integrate their spatial data.
Safe Software and FME came into existence because of this exact problem. Spatial data varies widely and is often stuck in formats that cannot be easily used by all applications, making it extremely difficult for GIS experts to make use of all the information they have.
While it was possible to transform proprietary formats in the past, much of the data would be lost in the conversion. Thus, FME was born. FME is recognized as the data integration platform with the best support for spatial data worldwide.
However, it can handle much more than just spatial data and can be easily used by IT and business professionals. Safe Software, the makers of FME, are leaders in the technology world that strive to stay one step ahead of the data integration trends. FME is continuously upgraded to ensure it has been adapted to support new data formats, updated versions of data formats, and large amounts of data.
Overview No matter what your interests are or what field you work in, spatial data is always being considered whether you know it or not.
Vector Vector data is best described as graphical representations of the real world. Raster Raster data is data that is presented in a grid of pixels. Attributes Spatial data contains more information than just a location on the surface of the Earth. Geographic Coordinate System To identify exact locations on the surface of the Earth, a geographic coordinate system is used.
Why Spatial Data? What is Spatial ETL? What is Geospatial Data?
Spatial Data Characteristics
A geographic information system GIS is a system designed to capture, store, manipulate, analyze, manage, and present all types of geographical data. The key word to this technology is Geography — this means that some portion of the data is spatial. In other words, data that is in some way referenced to locations on the earth. Coupled with this data is usually tabular data known as attribute data. Attribute data can be generally defined as additional information about each of the spatial features.
Spatial analysis or spatial statistics includes any of the formal techniques which studies entities using their topological , geometric , or geographic properties. Spatial analysis includes a variety of techniques, many still in their early development, using different analytic approaches and applied in fields as diverse as astronomy , with its studies of the placement of galaxies in the cosmos , to chip fabrication engineering, with its use of "place and route" algorithms to build complex wiring structures. In a more restricted sense, spatial analysis is the technique applied to structures at the human scale, most notably in the analysis of geographic data. Complex issues arise in spatial analysis, many of which are neither clearly defined nor completely resolved, but form the basis for current research. The most fundamental of these is the problem of defining the spatial location of the entities being studied.
A GIS file format is a standard of encoding geographical information into a computer file. A raster data type is, in essence, any type of digital image represented by reducible and enlargeable grids. Anyone who is familiar with digital photography will recognize the Raster graphics pixel as the smallest individual grid unit building block of an image, usually not readily identified as an artifact shape until an image is produced on a very large scale. A combination of the pixels making up an image color formation scheme will compose details of an image, as is distinct from the commonly used points, lines, and polygon area location symbols of scalable vector graphics as the basis of the vector model of area attribute rendering. While a digital image is concerned with its output blending together its grid based details as an identifiable representation of reality, in a photograph or art image transferred into a computer, the raster data type will reflect a digitized abstraction of reality dealt with by grid populating tones or objects, quantities, cojoined or open boundaries, and map relief schemas. Aerial photos are one commonly used form of raster data, with one primary purpose in mind: to display a detailed image on a map area, or for the purposes of rendering its identifiable objects by digitization. Additional raster data sets used by a GIS will contain information regarding elevation, a digital elevation model , or reflectance of a particular wavelength of light, Landsat , or other electromagnetic spectrum indicators.
shp files. Raster. Raster example Raster data is data that is presented in a grid of pixels. Each pixel within a raster has a.
Information Cartography: Using GIS for Visualizing Non-Spatial Data
Кажется, придется повозиться дольше, чем ожидалось, - это был звонок с мобильника. С мобильника, - мысленно повторил Нуматака. - Это кое-что. К счастью для японской экономики, у американцев оказался ненасытный аппетит к электронным новинкам.
Никто не проронил ни слова. Он снова посмотрел на Джаббу и закрыл. - Танкадо отдал кольцо с умыслом.
3 types of data
- И что же ты ответила. Она ткнула его в ногу носком туфли. - Я сказала нет! - И, выдержав паузу, добавила: - И до вчерашней ночи это была правда. В глазах Сьюзан Дэвид был самим совершенством - насколько вообще такое. Одно только ее беспокоило: всякий раз, когда они куда-то ходили, он решительно противился тому, чтобы она сама платила за. Сьюзан не могла с этим смириться, видя, как он выкладывает за их обед свою дневную заработную плату, но спорить с ним было бесполезно. Она в конце концов перестала протестовать, но это продолжало ее беспокоить.
Внезапный прилив энергии позволил ей освободиться из объятий коммандера. Шум ТРАНСТЕКСТА стал оглушающим. Огонь приближался к вершине. ТРАНСТЕКСТ стонал, его корпус готов был вот-вот рухнуть. Голос Дэвида точно вел ее, управляя ее действиями. Она бросилась к лестнице и начала подниматься к кабинету Стратмора. За ее спиной ТРАНСТЕКСТ издал предсмертный оглушающий стон.
Его парализовало от страха. - Adonde fue? - снова прозвучал вопрос. - Американец. - В… аэропорт. Aeropuerto, - заикаясь сказал Двухцветный. - Aeropuerto? - повторил человек, внимательно следя за движением губ Двухцветного в зеркале. - Панк кивнул.
Острая боль пронзила вес его тело, когда он приземлился на бок, но мгновение спустя он уже был на ногах и, скрываемый занавешенным входом, сбежал вниз по деревянным ступенькам. Превозмогая боль, он бежал через гардеробную. У алтаря кто-то кричал, за спиной у него слышались тяжелые шаги. Беккер толкнул двойную дверь и оказался в некотором подобии кабинета. Там было темно, но он разглядел дорогие восточные ковры и полированное красное дерево. На противоположной стене висело распятие в натуральную величину. Беккер остановился.
Откуда-то сверху накатывали приглушенные волны классической музыки.