QGIS/C2/Vector-Data-Styling/English-timed
From Script | Spoken-Tutorial
| 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. |
