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Time Narration
00:01 Welcome to this tutorial on Vector Data Styling in QGIS.
00:07 In this tutorial we will learn to,

Load vector data in QGIS

00:14 Style vector data using, Single symbol styling , Categorized styling, Graduated styling, and
00:25 Labeling features.
00:28 To record this tutorial I am using,

Ubuntu Linux OS version 16.04.

QGIS version 2.18.

00:39 To follow this tutorial you should be familiar with QGIS interface.
00:46 If not, For relevant tutorials, please visit our website.
00:51 To practise this tutorial, you need to download the folder given in the Code files link, located below the player.
01:01 Extract the contents of the downloaded zip file.
01:05 Locate world.shp file in the extracted folder.
01:11 I have already downloaded the code file, extracted and saved in a folder on Desktop.
01:19 Double-click on the code-file folder to open it.
01:24 Right-click on world.shp file.
01:29 From the context menu, select Open with QGIS Desktop option.
01:36 QGIS interface opens.
01:39 QGIS Tips dialog-box opens.
01:43 Click on OK button to close the dialog-box.
01:49 World map loads on the canvas in the default style.
01:54 You can see the world layer in the Layers Panel.
01:58 Right-click on the world layer.
02:01 From the context menu, select Open Attribute Table.
02:06 Attribute table for this layer opens.
02:10 Here we can see all the data of various features embedded in row and column format.
02:18 The country names are given in the ADMIN column.
02:22 Drag the slider at bottom of the table and navigate to POP_EST column.
02:30 In this column population for various countries is listed.
02:35 Next, we will depict the population data shown here, in various styles on the world map.
02:43 Close the attribute table.
02:46 Right click on the world layer.
02:49 From the context menu select Properties option.
02:53 Layer Properties dialog-box opens.
02:57 Click on Style tab from the left panel.
03:01 Various styling options are available in the Style tab.
03:05 Click on the drop-down button located on the top left corner of the dialog-box.
03:11 You will see various styling options here.
03:15 We will explore the first three in this tutorial.
03:19 Select Single Symbol option.
03:22 This option allows you to choose a single style.
03:27 The chosen style will be applied to all the features in the layer.
03:32 Click on add Symbol layer button available under Fill panel.
03:38 Various style options appear below Symbol layer type.
03:43 Since this is a polygon dataset, we have two basic choices.
03:48 You can fill the polygon with color and fill style of your choice.
03:55 Outline color, style and width can also be changed.
04:02 Click on the drop-down arrow next to Fill drop-down.
04:06 Color triangle opens.
04:09 Rotate the color triangle to choose the required color.

I will choose blue color.

04:17 Similarly, Select Outline color.
04:21 I will choose yellow.
04:25 Fill style as Dense1.
04:29 Outline style, solid line.
04:33 Outline width, 0.46 millimeters.
04:38 Various other style options are available to explore.
04:43 After you have completed the styling, click on OK button at the bottom-left corner of Layers Properties dialog-box.
04:52 On the canvas, you will see the new style applied to the layer with the style pattern you chose.
04:59 Now we will see how to map the population data.
05:03 The Single Symbol style is not very useful in mapping the population data.
05:09 Let us explore another styling option.
05:13 Right-click on world layer again and choose Properties option.
05:19 In the Layers Properties dialog-box, this time we will choose Categorized from the Style tab.
05:26 Categorized means, the features in the layer will be shown in different shades of a color.
05:33 These color shades are based on the unique values in the attribute fields.
05:39 Since we are trying to map population data, in the Column drop down we will select POP_EST.
05:48 Choose a colour ramp of your choice from the drop-down.

I will choose Blues.

05:55 Click on Classify button at the bottom of the middle panel.
06:00 The panel in the middle shows various classes with corresponding values.
06:07 Click on OK button at the bottom right corner.
06:11 On the world map, you will see different countries appearing in shades of blue.
06:17 Scroll down the central mouse button to zoom-in and zoom-out the map.
06:22 Lighter shades represent lower population.
06:26 Darker shades represent higher population.
06:31 Once again open Layers Properties dialog-box.
06:37 In Style tab, click on drop drown button.
06:41 Let us explore the Graduated symbology.

Select Graduated option.

06:48 Graduated symbology type allows you to break down the data in a column in unique classes.
06:55 We can choose a different style for each of the classes.
07:00 From the Column drop-down, select POP_EST.
07:06 We can think of classifying our population data into 3 classes, Low, Medium and High.
07:13 So, under Classes drop-down, select 3.
07:18 You will see that 3 classes show up in the panel with corresponding values.
07:25 Click on Classify button.
07:28 Click on Mode drop-down.
07:31 There are many Mode options available here.
07:35 To keep things simple, let us use the Quantile mode.
07:40 These modes use different statistical algorithms to break down the data into separate classes.
07:47 Also note that for an attribute to be used in Graduated style, it must be numerical field.
07:55 The numerical values can be Integer or Real values.
08:00 Attribute field with String type cannot be used with this styling option.
08:06 Click on OK button.
08:10 Now on the map you will see countries in 3 different shades of blue.
08:16 These color shades represents the population data for the country.
08:22 On the Layers Panel you will see 3 classes for this layer.
08:27 There are some more styling options available.
08:31 We can choose a different style and color for each of these classes.
08:37 Open Layer Properties dialog-box again.
08:42 In Classes tab, under Symbol column, double-click on the colored box.
08:49 Symbol Selector dialog-box opens.
08:53 In the Color drop-down option, click on the drop-down arrow. Color triangle opens.
09:01 Rotate the color triangle to choose the required color.
09:05 I will choose red color to indicate low population.
09:10 Click on OK button in the Symbol selector dialog-box.
09:15 Similarly change the color for other two classes.
09:19 I will choose yellow for the medium and green for high.
09:35 Double-click on the first row in the Legend column.

Type low for the first row.

09:42 Type Medium for the second row.

And High for the third row.

09:48 Double-click on the first row under Values column to edit the selected ranges.
09:54 Enter class bounds text box opens. If you wish, you may edit lower value and upper value.
10:04 For now we will leave the values unchanged.

Click on OK button.

10:10 Click on OK button in the Layer Properties dialog box.
10:15 Observe the world map.
10:17 Now we have 3 different colors to represent low, medium, high population.
10:24 Observe the Layers Panel.
10:27 There are clearly marked class names and colors to represent our interpretation of the population values.
10:36 This style conveys a lot more useful map than the previous two attempts.
10:42 Let us learn how to label different features in a vector file.
10:47 For demonstration let us label the names of the countries.
10:52 Open Layer Properties dialog box again.
10:57 From the left panel, select Labels tab.
11:01 In the first text box drop-down, select Show labels for this layer.
11:08 ADMIN column in the attribute table has list of the names of the countries.
11:14 So in the Label with drop down, select ADMIN.
11:20 In the style menu, Select Buffer.
11:23 Check the Draw text buffer check box.
11:27 Size of the text can be changed according to requirement.
11:32 Select a color from the color drop-down.
11:38 Click on OK button.
11:40 On the world-map we can see the names of countries displayed.
11:46 Let us summarize,
11:48 In this tutorial we have learnt to

Load vector data in QGIS

11:55 Style vector data using, Single symbol styling, Categorized styling, Graduated styling, and
12:07 Labeling features.
12:10 As an assignment,
12:12 Categorise the data set POP_EST into 5 classes.
12:19 Use Graduated styling method, Equal Interval mode.
12:24 Your completed assignment should look as shown here.
12:29 The video at the following link summarises the spoken tutorial project.

Please download and watch it.

12:37 The spoken tutorial project team conducts workshops and gives certificates on passing online tests

For more details please write to us.

12:48 Please post your timed queries on this forum.
12:53 The Spoken Tutorial Project is funded by NMEICT, MHRD Government of India.

More information on this mission is available at the following link.

13:05 This is contributed by Prajwal.M from NIT Surathkal and Snehalatha from IIT Bombay.

Thank you for joining.

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