Upgrade to remove ads
Terms in this set (77)
What is a GIS?
A Geographic Information System (GIS) is a computerized system designed for the storage, retrieval, and analysis of geographically referenced data. GIS is also a key technology for managing the daily operations of organizations
spatial data is essentially any data that can be mapped, is information about a physical object that can be represented by numerical values in a geographic coordinate system.
Analysis of spatial data allow us to illustrate
-Where, how, why
-Past, present, future
Questions we answer using a GIS
What exists at a particular location?
Where are certain conditions satisfied?
What has changed in a place over time?
What spatial patterns exist?
What if this condition existed at this location?
What are the variables?
What is a basemap
a data layer, contains features users can interact
show a region of the map, geographic boundaries to gis map
what does "zoom to full extent" result in
see the whole map in the frame centralized
What is raster data:
array of cells, each cell displayed with color fill from a band of values. grid like data, each cell has own value
What is vector data:
major data source, uses points lines polygons to show the layer
What is a bookmark
A geographic location you want to save and reference later
What is an attribute table
table to symbolize a single-band mosaic dataset or raster dataset
something thats a character. Row
column in a attribute table, can hold data. ex . name of a building
a thematic map in which areas are distinctly colored or shaded to represent classed values
What is a definition query:
displays a subset of features from a larger collection.
What is a density map
Show the density of something
How can you make your maps
online or hardcopy, electronic document
how can you make your maps readable?
Legends scales and titles
how can u make ur maps tell a story?
Provide context, sources quality of data analysis and limitations
What is a layout?
arrangement of elements on a map, legends tables etc
the purpose of guides
helps you align the map in the way you want. Cleans up the map
data help you navigate a map, info to interpret symbols
Visibility ranges - why would you set them?
So if you don't want something coming up when you're at a certain extent you set them.
What is a story map?
hey combine text, maps, multimedia, and they tell a story
What is a database
container for storing data
What is a file geodatabase
simplified database for geospatial data. Allows data to be related and joined.
What is a shapefile:
old format for single map layer. Not preferred still used tho. Can import to file geodatabases.
What is a CSV file:
comma separated values, first row attribute tables, data separated by commas. End of row indicated by non printing character
need each table to have an attribute with matching values stored as the same data type
Distance north or south of the equator
Distance east or west of the prime meridian, measured in degrees
23.5 degrees north is the
tropic of cancer
23.5 degrees south
Tropic of Capricorn
Latitude first, then longitude for writing coordinates - Westbury, NY (41 degrees north, 74 degrees)
flat map of earth exactly same shaped countries - most common in what we see in schools. Used for navigation.
An official record of the dimensions and value of land parcels, used to record ownership and assist in calculating taxes.
Structured Query Language (SQL)
asks users to write lines of code to answer questions against a database
Large Scale Map Extent
Shows small area/extent with more detail
Small Scale Map Extent
Show large area/extent with less detail
Geographic Coordinate System
uses three dimensional spherical surface to define locations on the earth.
Projected Coordinate System
on a flat two dimensional surface, Unlike a geographic coordinate system, a projected coordinate system has constant lengths, angles, and areas across the two dimensions. A projected coordinate system is always based on a geographic coordinate system that is based on a sphere or spheroid.
State Plane Coordinate System
coordinate system that divides 50 states into 120 numbered sections.
Universal Transverse Mercator, divided up in 60 north and south sections. 6 degrees wide.
A projection whose surface intersects the surface of a globe. No distortion at the lines of intersection.
preserve the shape of the features on the map
place a cylinder around a globe and unravel it to get the cylindrical projection
place a cone around a globe and unravel it to get the conic projection
file format used to display geographic data in an Earth browser such as Google Earth.
TIGER/Line files are a digital database of geographic features, such as roads, railroads, rivers, lakes, political boundaries, and census statistical boundaries, covering the entire United States
•A geoprocessing command that removes boundaries between adjacent polygons that have the same value for a specified attribute.
hey zane a great example of this would be combining west Germany with east Germany to create Germany. Or combining VT, RI, MA, CT ME, and NH to make New England
takes a feature class from one layer and extracts it, creating a new feature class. helpful for studying areas of interest
Combining features from multiple data sources of the same data type into a single, new dataset.
Adding features from multiple data sources of the same data type into an existing dataset.
Computes a geometric intersection of the input features. Features or portions of features which overlap in all layers and/or feature classes will be written to the output feature class.
Computes a geometric union of the input features. All features and their attributes will be written to the output feature class.
Geocoding is the process of transforming a description of a location—such as a pair of coordinates, an address, or a name of a place—to a location on the earth's surface.
what kinds of locations can you find with geocoding???
- points of interest
- names of mountains, bridges, etc..
address data analysis
you can display address locations and begin to recognize patterns with the information
customer data management
maintains address information for each customer or client
geocoding allows you to take your customers information and create and map of their locations.
distribute geocoding applications
You can use various methods to share your geocoding functionality.
the major component in the geocoding process
includes a snapshot of the address attributes in the reference data and the queries for performing a geocoding search.
a polygon surrounding map features of a feature class. A polygon enclosing a point, line or polygon at a specified distance
" what's near what?" allows you to compare multiple locations and the distance between them
creates a join from one layer's attribute table are appended to another layer's attribute table based on the relative locations. Can have one-one join, or one-many join.
spatial overlays are a set of methods for transferring data between objects in drawings based on their spatial relationships to each other.
defines space as an array of equally sized cells arranged in rows and columns, and composed of single or multiple bands. Each cell contains an attribute value and location coordinates.
Properties of raster data sets
cell based map layer,
includes image formats,
all raster data sets are arrays of cells or pixels.
Each cell has a value and location and rendered with a color when mapped.
All raster data set have at least one band of values.
A band is comparable to an attribute for a vector map layer
provides a way to visualize elevation
the vertical distance of a point or object above or below a reference surface or datum(generally mean sea level)
a line on a map that connects points of equal elevation based on a vertical datum, usually sea level
Kernel density or heat map:
shows the geographic clustering of a phenomenon
threshold areas create polygons around locations. The radius of the polygon is determined by expanding from the location until it meets your criteria
TIN is defined by two elements: a set of input points with x-, y-, and z-values, and a series of edges connecting these points to form triangles.
for large extent in a projected coordinate system, when the curvature of the earth is important. Fixed coordinate system can not be changed.
Local scene and tin surface
used for smaller extent content in a projected coordinate system, allows users to clip features to study area
Z enabled features
value for a given surface location that represents an attribute other than position.
YOU MIGHT ALSO LIKE...
GIS Key Terms
GIS 250 Midterm
GEOG373 Exam 2
OTHER SETS BY THIS CREATOR
Biostats test 2 vocab
christian saints final
OTHER QUIZLET SETS
Acct. 324: chapters 23-24
Vertebral Column and Thoracic Cage
גניבת דעת + hurtful words
Quarter 3 WH