Geo 160 Exam 1 Flashcards
Datum
Measurements, Records
Information
Records that have meaning to you
Knwoledge
Information you are ready to act upon
variables
data relevant to a particular problem (Car color)
Values
Silver
what is geographic data
data that contaisn coordinates
what is an attribute
a geographic variable
name 2 things all coordinate systems require
origin and oreintation
projection
a systematic transformation from a round surface to flat surface
developable surfaces
surfaces that can be turned into a plane
name 2 developable surfaces
cone and cylinder
what do equal area maps preserve
surface area of depicted objects across entire map
what do conformal maps preserve
the shapes of small features, but not across the entire map
what do equidistant maps preserve?
scale along specific lines, but not entire map
what do azimuthal projections preserve
directions from one selcted point to all other points on map
Reference maps
Have no single stpry about them - multiple purposes
reference map examples
google maps, topo maps
thematiuc maps
tell a storey about spatial phenomenom
5 steps of the cartographic process
Data selection Spatial simplification Smoothing, aggregation, typification (e.g. cartograms) Spatial exaggeration Data classification Data symbolization
data symbolization
color, hue, etc
name 3 common data classification processes
equal interval, quantile, manual
feature
the where of a spatial object
attribute
the what of a spatial object
the three msot typical ways to talk about the “where?”
through points, lines, and polygons
nominal
qualitative categories that cannot be ordered
ordnial
qualitative categories that have natural order
interval
numbers that can be negative
ratio
numbers that cannot be negative
database
organized collection of data
simplest way to organize data
table
what is the column of columns of a table called
the primary key
dbms
database management systems
metadata
data about your data
georgraphic data made using geometricprimitives
vector data
geograpic data using a regular grid
raster
a table containg information on all gps satellites
almanac
precision
consistency of measurements
accuracy
how close you get to the target, oin average
scale orientation
map’/IRL
polar coordinate
degree of angle and distance from origin
cartesian
simple plotting system
geographic
lat and long
quantile
break data into 4 equal catagories
equal interval
make a scale from high to low and break scale ito 4 catagories
gdop
geometric delusion of position
dgps
differential gps - finds errors to get more accuracy
waas
wide area augmentation system - grid of base receivers across USA to correct accuracy
rtk
real time kinjematic - accuracy of 1-2mm
what does gps work on
a geocentric system that doesn’t use lat and ;long
wgs84
world geodetic system
trilateration
location of objects through distance
triangulation
location of objects through angles
