ewce09.azraftaohid.me/L4T1/EWCE 464/TUTORIAL 04_SPATIAL ANALYSIS/C01 - Class notes.md

---

share_link: https://notesx.azraftaohid.me/lftrvh1f share_updated: 2026-08-17T19:45:42+06:00

Spatial Analyst Tutorial

• Exercise 1 to 4; 4 is not included for examination.

Introduction

• US Stowe city.
• Large number of people migrated here
• Consequently, number of children increased
• Crowded school
• Requirements:
  • New school on flat ground
  • Near recreational sites
  • No near existing school
  • Near road
  • Not near water area
  • In empty space

Geodatabase

• Geoprocessing > Environments > Workspace

• Current workspace is useful for or if source files are under one geodatabase

• Scratch workspace is useful for default output geodatabase

• Save and close

• Add data

• All data except destination

• Geoprocessing > Environments > Output Coordinates

• Set default coordinate system

• Set "Output Coordinate system" to Same as Layer "elevation"

• Geoprocessing > Environments > Processing Extent

• Set "Extent" to Same as layer elevation

• Geoprocessing > Environments > Raster Analysis

• Set "Cell Size" to Same as layer elevation

Find Flat Surface

• Spatial Analyst Tools > Surface > Slope
• Use intput "elevation"
• 'z factor' -> conversion between meter and feet: 0.3048; because z unit is in meter but elevation is in feet
• Preferrable is 0 - ~3

Proximity of Recreational Sites

• Spatial Analyst Tools > Distance > Euclidean Distance
• Use input as "rec_sites"
• Optionally change symbol for rec_sites for better understanding
• Preferrable is ~0

Proximity of School Sites

• Spatial Analyst Tools > Distance > Euclidean Distance
• Use input as "schools"
• Optionally change symbol for schools for better understanding
• Preferrable is ~16947

[!Note] Note Preferrable is not reclassify all three (slope, rec, school) into same number of classes

Reclassify

• Spatial Analyst Tools > Reclassify > Reclass
• Input "Slope"
• Choose classification
  • Method: "Equal Interval"
  • Classes: 10
• Press "Reverse New Values" to have lower slope area as 10
• Do the same but for "EucDist_Recreational"; perform reverse
• Do the same but for "EucDist_School"; do not perform reverse

Weighted Overlay

• Spatial Analyst Tools > Overlay > Weighted Overlay
• Set "Evaluation scale" to 1 to 10 by 1 $$scrolldown\left(ifrequired\right)$$
• Add "Relcassed_Slope", "Reclassed_Recreational", "Reclassed_School"
• Further add "landuse" with input field "LANDUSE"
  • Manually rank landuse
  • Use ranks from manual
  • During exam, these ranks may or may not be provided; use own judgement
• Use influence:
  • Slope: 13%
  • Recreational: 50%
  • School: 25%
  • Landuse: 12%

Filter Out Nonsuitable Areas

• Spatial Analyst Tools > Conditional > Con
• Use input as "Suitable_Areas"
• Expression Value = 9
• Input true raster Suitable_Areas

Filter Out Small Suitable Areas

• Spatial Analyst Tools > Generalization > Majority Filter
• Use input as "Optimal_Areas"
• "Number of neighbors to use" to "EIGHT"

Filter based on Area Requirements (10 acre or 40469 m^2) and Road Connectivity

Convert to Polygon

• Convsersion Tools > From Raster > Raster to Polygon
• Input = Filtered_Areas

Intersects to Road

• Data Management Tools > Layers and Table Views > Select Layer by Location
• Input Feature Layer = Opt_Area
• Relation = INTERSECT
• Selecting Features = roads

[!NOTE] Important Do not clear selection

Filter by Area

• Data Management Tools > Layers and Table Views > Select Layer by Attribute
• Layer Name = Opt_Area
• Selection type = SUBSET_SELECTION
• Expression = Shape_Area >= 40469

Export

• Opt_Area > Data > Export Data
• Export = Selected features
• Save to a location with type = Shapefile

---

[!NOTE] Processing Extent Leftmost, rightmost, topmost, and bottommost boundary See extent for a layer: Properties > Extent