Raster Analysis

Question 1

resolution

Answer 1

the distance of one edge of a pixel.

Question 2

Boolean layer

Answer 2

logic layer (1s and 0s)

Question 3

What is the function of reclass?

Answer 3

• creates a new layer
• simplifies and generalizes
• low, med or high log volume per hectare (vols grouped to classes)

Question 4

what are the uses of reclass?

Answer 4

• convert raw data to classes
• create boolean (logic) layers
• bring layers to a common scale (i.e. suitability: 0-10)

Question 5

What is the math function of raster?

Answer 5

conduct math on maps

• operates on a single layer
• a formula applied to each pixel
• used to convert distances or elevation to temp.

Question 6

What are math operators?

Answer 6

• operates on 2 or more layers
• arithmetic (subtract 2 layers to view change)
• relational (ex finding max value from 3 separate hazard maps)
• boolean (and/or/not)

Question 7

What is interpolation?

Answer 7

using referenced values to generate new data on the vector layer. ex(spot heights)

• closer values carry more weight
• checker board

Question 8

How is slope represented in surface analysis?

Answer 8

-rate of change in E

Question 9

How is aspect represented in surface analysis?

Answer 9

• downhill direction that a slope faces

- direction of change

Question 10

What is the purpose of hill shading?

Answer 10

provides a realistic look

• can be used to assess level of illumination on a surface
• can alter direction for time of day

Question 11

what is viewshed?

Answer 11

Refers to the line of sight from a given point. Used often in forestry.

Question 12

What are applications of viewshed?

Answer 12

• line of sight communication for cell towers

- VQO in forestry

Question 13

What are is the proximity function of surface analysis?

Answer 13

-distance as a continuous variable from features
-buffers can be created using
distance layer
reclass layer

Question 14

What does extents refer to?

Answer 14

Size