Hierarchical Cluster Analysis using QGIS and R - Revision history

OwenKirkham: /* Heatmap for trees injected against EAB */

2024-10-02T18:01:08Z

Heatmap for trees injected against EAB

OwenKirkham: /* Splitting Vector Layers */

2024-10-02T17:59:54Z

Splitting Vector Layers

OwenKirkham: /* Splitting Vector Layers */

2024-10-02T17:58:38Z

Splitting Vector Layers

OwenKirkham: /* A Multi-Criteria SQL Feature Selection */

2024-10-02T17:58:10Z

A Multi-Criteria SQL Feature Selection

OwenKirkham: /* A Multi-Criteria SQL Feature Selection */

2024-10-02T17:55:58Z

A Multi-Criteria SQL Feature Selection

OwenKirkham: /* A Multi-Criteria SQL Feature Selection */

2024-10-02T17:54:53Z

A Multi-Criteria SQL Feature Selection

OwenKirkham: /* A Multi-Criteria SQL Feature Selection */

2024-10-02T17:54:31Z

A Multi-Criteria SQL Feature Selection

OwenKirkham: /* A Multi-Criteria SQL Feature Selection */

2024-10-02T17:52:08Z

A Multi-Criteria SQL Feature Selection

OwenKirkham: /* Loading the csv data */

2024-10-02T17:51:22Z

Loading the csv data

OwenKirkham: /* Purpose */

2024-10-02T17:47:44Z

Purpose

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 [[File:twentyone.PNG]]
-*A window will open for the Heatmap Plugin. Use the ASH_TREE_SPECIES_TREATMENT_EAB as the input point layer, name the output raster, and set the radius to 150m. Your window should look like the following.
+*A window will open for the Heatmap Plugin. Use the Tree_Inventory_TREATMENT_EAB as the input point layer, name the output raster, and set the radius to 150m. Your window should look like the following.
 [[File:twentytwo.PNG]]

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 [[File:nine.png]]
-*A window will open for the Split vector layer tool. Select the ASH_TREE_SPECIES layer as the input vector layer and TREATMENT as the unique field ID. Select the output folder where you want the files to be saved or create a new folder by clicking '''Browse'''. Once a folder has been selected click '''OK'''.
+*A window will open for the Split vector layer tool. Select the Tree_Inventory layer as the input vector layer and TREATMENT as the unique field ID. Select the output folder where you want the files to be saved or create a new folder by clicking '''Browse'''. Once a folder has been selected click '''OK'''.
 [[File:ten.PNG]]
 *The program will alert you when the task is complete. However, the two new layers will not automatically load into your map so you must either add them using the '''add vector layer tool''' or select them from the appropriate folder in the '''browser''' section of the main menu. If you need a refresher as to how to do this refer back to the add shapefile section of this tutorial.
-*Once added, you will find that they have been automatically named either ASH_TREE_SPECIES_TREATMENT_EAB or ASH_TREE_SPECIES_TREATMENT_NULL.
+*Once added, you will find that they have been automatically named either Tree_Inventory_TREATMENT_EAB or ASH_TREE_SPECIES_TREATMENT_NULL.
-'''Splitting the ASH_TREE_SPECIES TREAMENT_EAB vector layer further '''
+'''Splitting the Tree_Inventory TREAMENT_EAB vector layer further '''
-In this section we want to split the ASH_TREE_SPECIES_TREATMENT_EAB vector layer further, by splitting the data by city ward. To achieve this, repeat the methods used previously in this section which used the Split Vector Layer tool.
+In this section we want to split the Tree_Inventory_TREATMENT_EAB vector layer further, by splitting the data by city ward. To achieve this, repeat the methods used previously in this section which used the Split Vector Layer tool.
-*Once the tool is open select the ASH_TREE_SPECIES_TREATMENT_EAB layer as the target layer and the WARD field as the Unique ID field.
+*Once the tool is open select the Tree_Inventory_TREATMENT_EAB layer as the target layer and the WARD field as the Unique ID field.
 [[File:eleven.PNG]]

← Older revision		Revision as of 17:58, 2 October 2024
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	In the later sections we will need to analyze ash tree data based on whether or not they have been injected against EAB (emerald ash borer) infestation or not. If you open up the attribute table for the ~~ASH_TREE_SPECIES~~ layer, you will notice that there is a field called TREATMENT. This field indicates whether each ash tree has been injected against EAB, trees that have been injected against EAB will contain the value '''EAB''' in the TREATMENT column, whereas trees that have not been injected will contain the value '''NULL'''.		In the later sections we will need to analyze ash tree data based on whether or not they have been injected against EAB (emerald ash borer) infestation or not. If you open up the attribute table for the Tree_Inventory layer, you will notice that there is a field called TREATMENT. This field indicates whether each ash tree has been injected against EAB, trees that have been injected against EAB will contain the value '''EAB''' in the TREATMENT column, whereas trees that have not been injected will contain the value '''NULL'''.

	To split up the data between EAB and NULL treatments we could use a methodology similar to the previous section, by selecting features and creating a new layer. However, a quicker alternative is to use the '''Split Vector Layer''' tool. The Split Vector Layer tool splits up vectors by selected fields and creates new vectors based on groups of field values. It is useful for splitting up fields that have many field values, but is generally used to split fields that have discrete categorical data.		To split up the data between EAB and NULL treatments we could use a methodology similar to the previous section, by selecting features and creating a new layer. However, a quicker alternative is to use the '''Split Vector Layer''' tool. The Split Vector Layer tool splits up vectors by selected fields and creates new vectors based on groups of field values. It is useful for splitting up fields that have many field values, but is generally used to split fields that have discrete categorical data.

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 [[File:seven.PNG]]
-*Once the query has been entered choose the '''select''' button and close the window. Notice that in the attribute table window the number of selected features is shown. From the selection query there should be '''18,129 features selected'''.
+*Once the query has been entered choose the '''select''' button and close the window. Notice that in the attribute table window the number of selected features is shown. From the selection query there should be '''25,115 features selected'''.
 *To see the selected features choose use the move selection to the top button ([[File:B.png]]), to see the species in alphabetical order you can click on the species column.

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 '''Now we want to get rid of all non-ash species data from this layer.'''
 *Click the '''toggle editing mode''' button([[File:B2.png]]) to turn on the editing function.
-*Choose the '''invert selection''' button ([[File:Invert.png)]]) to invert the selection so that all non-ash species are selected. The table should look similar to the one bellow.
+*Choose the '''invert selection''' button ([[File:Invert.png]]) to invert the selection so that all non-ash species are selected. The table should look similar to the one bellow.
 [[File:eight.PNG]]

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 The purpose of this part of the tutorial is to identify all true ash tree species data points from the City of Ottawa tree inventory vector layer. The features selection tool is used to select features from an attribute table using SQL (Structured Language Queries)
-*In the layers window, right click the “Tree_Inventory_Apr 2013” vector layer, then from the drop down menu select '''Open Attribute Table'''. Your attribute table should look something like this.
+*In the layers window, right click the “Tree_Inventory” vector layer, then from the drop down menu select '''Open Attribute Table'''. Your attribute table should look something like this.
 [[File:five.PNG]]

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 ==='''Loading the csv data'''===
-Once the census data file is downloaded from this webpage, open it and copy all the contents of the table. Open the program excel or another spreadsheet program, paste the data into the spreadsheet using match destination formatting and then save the file as a csv. Open the program Notepad, type "String","Integer" and save the file as a csvt using the exact same name as the csv file. This is an important step because it prevents QGIS from discarding the zeros that follow the decimal place in the census tract geocodes when it is imported.
+Once the census data file is downloaded from this webpage, open it and copy all the contents of the table. Open the program Excel or another spreadsheet program, and format the CTUID cells as text. Then save the file as a CSV.
-*To load the table into QGIS in the main menu select '''Layer''', then select '''Add Layer''' from the drop down menu and then select '''Add Delimited Text Layer'''.
+*To load the table into QGIS, in the main menu, select '''Layer''', then select '''Add Layer''' from the drop-down menu and then select '''Add Delimited Text Layer'''.
 [[File:Three.png]]
-*The Create a layer from a delimited text file window will open. In the new window select the '''Field_1788 csv''' file. All other selections should look like the following. Once complete, select '''OK'''.
+*The Create a layer from a delimited text file window will open. In the new window, select the '''Income_Stats_Ottawa_2020''' file. All other selections should look like the following. Once complete, select '''OK'''.
 [[File:Four.PNG]]

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 ==Purpose==
 The purpose of this tutorial is to familiarize users with open source software and to teach them how to manipulate, process, and map using freely accessible data. This tutorial will teach users skills such as:
-*adding shp and csv data
+*adding shp and csv data to QGIS
 *preforming complex attribute queries
 *creating new layers from selected features