Term
|
Definition
-represent points, lines, and polygons
-grid cells have integer values representing feature class code
*have to have an attribute table in the metadata to tell you what the integers mean |
|
|
Term
|
Definition
-represent surfaces
-use decimal values representing measurements
-every grid cell can have a unique value
-usually decimals
-ex: elevation, temp, barometric pressure |
|
|
Term
| can you tell the units of a raster by looking at it? |
|
Definition
| No, you need to have metadata |
|
|
Term
| if a raster is unprojected, the grid cell size is represented by: |
|
Definition
| decimal degrees/ arc second |
|
|
Term
| the appoximate cell size in meter when the cell is: 0.000278, 0.000278 (decimal degrees or 1 arc second ) |
|
Definition
30m x 30m (equator)
30m x <30m (n/s x e/w) |
|
|
Term
| how large is a decimal degree on the geographic grid? |
|
Definition
longitude= length of a degree varies (largest at equator- about 69 miles or 111km)
latitude= length of a degree is about constant (69mi or 111km) |
|
|
Term
| does the length of a decimal degree vary with latitude or longitude? |
|
Definition
|
|
Term
| one decimal degree= ___ arc seconds? |
|
Definition
60 arc minutes, or
216000 arc seconds |
|
|
Term
|
Definition
|
|
Term
| for an unprojected raster in AK, what happens to grid cell shape if we project the data frame? |
|
Definition
|
|
Term
| for an unprojected raster in AK, what happens to grid cells if we project the raster dataset? |
|
Definition
|
|
Term
| why do we often want to project the raster? |
|
Definition
| you need to project the raster if you want to run most analyses |
|
|
Term
| How do you project a raster? |
|
Definition
| Toolbox> Data Management> Projections and Transformations> Raster> Project Raster |
|
|
Term
|
Definition
30m, originally derived from the contour lines on topo map separates, 1:24,000
Source: USGS |
|
|
Term
| 1/3 arc second data is _____ |
|
Definition
10m,they chopped up the 30m data, but it's no better than the 30m data
Source:USGS |
|
|
Term
| 1/9 arc second data is _______ |
|
Definition
3m, from lidar
source: USGS |
|
|
Term
| 30 arc seconds data is _______ |
|
Definition
900m (about a km), from mean grid cell aggregation (took SRTM and aggregated grid cells (generalized))
Source:GMTED2010 |
|
|
Term
| 60 arc seconds data is _______ |
|
Definition
|
|
Term
| How do you turn on the spatial analyst extension? |
|
Definition
| Click on the customize tab at the top, click extensions, check the spatial analyst option. |
|
|
Term
| Two ways to mosaic a raster: |
|
Definition
1. Data Management> raster> raster dataset> mosaic to new raster tool
2. Raster calculator: newraster= raster1, raster2 |
|
|
Term
| Two ways to reproject a raster: |
|
Definition
1. Data Management> Projections and Transformations> Raster> Project Raster tool
2. Export the raster from a projected data frame |
|
|
Term
| Two ways to clip a raster: |
|
Definition
1. Data Management> Raster> Raster Processing> Clip tool
2. Raster Calculator, click on environment settings> processing extent> set extent |
|
|
Term
| how do you mask a raster to conform to a polygon |
|
Definition
| environment settings> raster analysis> set Mask |
|
|
Term
| how do you resample a raster to a different cell size |
|
Definition
|
|
Term
|
Definition
| create a vector file from a raster |
|
|
Term
|
Definition
MUST PROJECT
gives the slope of your terrain |
|
|
Term
|
Definition
gives the direction of the rock faces
flat surface is a -1
north facing slope =0
22.5 degree increments |
|
|
Term
|
Definition
| effect that helps display elevation data |
|
|
Term
|
Definition
| Determines the raster surface locations visible to a set of observer features |
|
|
Term
|
Definition
| The CutFill function enables you to create a map based on two input surfaces — before and after — displaying the areas and volumes of surface material that have been modified by the removal or addition of surface material. |
|
|
Term
| what is an "offset" in the viewshed tool? |
|
Definition
| how high off the ground your "eyes" would be |
|
|
Term
| what is the viewshed tool output? |
|
Definition
visible/not visible terrain
0= not visible
1=visible from one point
2= visible from 2 pts... etc |
|
|
Term
| What are the interpolation methods in ArcGIS? |
|
Definition
IDW
spline
kriging
natural neighbor
tend surface |
|
|
Term
|
Definition
| Inverse Distance Weighted |
|
|
Term
| IDW is deterministic or stochastic? |
|
Definition
|
|
Term
In an IDW interpolation
1. a surface can/cannot exceed the highest and lowest values in the dataset?
2. a surface does/does not have to pass through the sample points |
|
Definition
|
|
Term
| Spline is deterministic or stochastic? |
|
Definition
|
|
Term
In a spline interpolation
1. a surface can/cannot exceed the highest and lowest values in the dataset?
2. a surface does/does not have to pass through the sample points |
|
Definition
|
|
Term
| Is kriging deterministic or stochastic? |
|
Definition
|
|
Term
In a kriging interpolation
1. a surface can/cannot exceed the highest and lowest values in the dataset?
2. a surface does/does not have to pass through the sample points |
|
Definition
|
|
Term
| are the differences between interpolation methods great or small? |
|
Definition
| small differences in most cases when actually applied |
|
|
Term
| What is important about 3D Analyst licensing? |
|
Definition
| It is a separate extension from the core software |
|
|
Term
| what does 3D analyst extension provide? |
|
Definition
| tools and functionality to work in a 3D environment (analysis and visualization) |
|
|
Term
| What is required in order to work with TIN data? |
|
Definition
|
|
Term
|
Definition
| triangulated irregular network |
|
|
Term
why are there duplicate tools in 3D analyst and Spatial Analyst?
Are these tools different? |
|
Definition
You can buy the extensions separately, so they wanted to make sure you had them no matter which one you bought.
No, they're exactly the same. |
|
|
Term
| Do the tools in 3D analyst only work on TINs? |
|
Definition
| No, many of them work on rasters too. |
|
|
Term
when you load 3D analyst you get:
(2 things) |
|
Definition
1. 3D analyst toolbar
2. 3D analyst tools added to ArcToolbox |
|
|
Term
| What two application programs come with 3D Analyst? |
|
Definition
1. ArcScene
2. ArcGlobe
(allow users to visualize data in a 3D environment) |
|
|
Term
| What are the two primary things 3D analyst are used to create? |
|
Definition
1. 3D TIM
2. 3D Features on that TIM |
|
|
Term
| 3D TIN models of a terrain are usually made how? |
|
Definition
| from a raster DEM (which stands for...... Digital Elevation Map) |
|
|
Term
| TINs can be used to.... (5 functions) |
|
Definition
1.create contour maps
2. slope maps
3. aspect maps
4. shaded relief (hillshade)
5. viewshed |
|
|
Term
| what does a 3D feature consist of? |
|
Definition
|
|
Term
| Which of the three (points, lines, polygons) can 3D features be? |
|
Definition
| all three can be made from vector data |
|
|
Term
| how do you convert 2D to 3D data? |
|
Definition
| add a z value (height) in the attribute table |
|
|
Term
| can you overlay 3D features on a raster DEM, a TIN elevation model, or both |
|
Definition
|
|
Term
| ArcGIS Online is hosted by____ |
|
Definition
|
|
Term
| who can create an online folder on ArcGIS? |
|
Definition
| anyone with an Esri Global Account |
|
|
Term
| What can you upload to an online folder? |
|
Definition
| data layers that are then overlaid onto an ESRI basemap |
|
|
Term
| what can be symbolized and stored in the cloud once they are uploaded? |
|
Definition
|
|
Term
| What can you do once data layers are uploaded onto the cloud? |
|
Definition
1. share map with the public through ArcGIS online search
2. embed map in a web page or a web application |
|
|
Term
| How do you make distance surfaces? |
|
Definition
ArcToolbox> Spatial Analyst> Distance
review from last exam |
|
|
Term
| any analysis involving distance, direction, and allocation ____ |
|
Definition
MUST BE PROJECTED (don't forget)
review from last exam |
|
|
Term
| what are the three types of density surface? |
|
Definition
pint, line, and kernel (point or line)
review from last exam |
|
|
Term
| Which of the three density surfaces can be weighted with an attribute value? |
|
Definition
all three (point, line, and kernel)
trick question! |
|
|
Term
| any analysis involving density ____ |
|
Definition
MUST BE PROJECTED! (don't forget)
review from last exam |
|
|
Term
| in raster statistics, zonal statistics is used for: |
|
Definition
| generating a table of statistics from a raster based on a polygon layer |
|
|
Term
what is a straight line distance surface?
(what is the other name for it and what is it?) |
|
Definition
Euclidean distance
Calculates, for each cell, the distance to the closest source |
|
|
Term
| what is a direction surface? |
|
Definition
|
|
Term
| what is an allocation surface? |
|
Definition
|
|
