Layout in Metview
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The download for this session is contained on the page Analysis Views.
Plot Layout
Sophisticated layouts are possible in Metview, with multiple plots on a single page as shown below:
To demonstrate the layout facility in Metview, let’s re-create the above plot. The Display Window icon allows us to design a layout, and also to choose the size of the page (e.g. A4).
Instantiate a new Display Window icon and edit it. This is what you will produce over the next few steps:
Click on the Add new frame button to create the first frame. By default, this contains just a single plot scene which uses a Geographic View. Select (left-click) this plot scene and click Expand selected frames to make it fill the whole area. Divide it up into three areas as follows:
click Split selected frames, select 2x1 in order to obtain two vertically stacked frames and click OK.
select (left-click) the lower frame, click Split selected frames and select 1x2.
Give a different View to each scene:
drag a Cross Section View icon (either one you previously created or else a new one) into the top scene.
drag a Vertical Profile View icon into the bottom-left scene.
drag a Geographic View icon into the bottom-right scene.
Save the changes and Visualise this icon. Drag the t_fc96.grib icon into all three of the scenes in the Display Window (each of the frames defined in the editor is referred to as a scene in the Display Window. Apply some Visdefs:
drag the shade icon into the cross section scene.
drag the vdline icon into the vertical profile scene.
Your result should look something like the plot at the start of this section.
If you look at the Frames and, more interestingly, the Layers tabs, you will see that they are linked to only one of these scenes at a time. Try using the Active scene control to change which one is used (you can visually highlight the active scene from the View menu). You can also right-click on a scene and choose “Select as active scene” from the context menu.
Generate a macro from this plot by clicking on the Generate macro button in the toolbar. This is a great way to interactively design a plot layout and then create a macro which uses it. To run it on a day-to-day basis, probably only the data file reading step would have to be modified.
Legend
Legends are an important part of any scientific and operational plot. If enabled, an automatic legend will be built from the data provided.
To enable a legend, parameter Legend needs to be set to On. This parameter is available in some of the Visual Definition icons (e.g. Contouring, Graph Plotting and Wind Plotting).
To specify how a plot’s legend is displayed, Metview provides a specific icon, named Legend. This controls features such as the legend’s position, style and fonts. To demonstrate the Legend’s concept, do the following:
Visualise icon t_fc24.grib.
drop icon shade into the Display Window (verify that parameter Legend is set to On).
The result shows a default legend sitting at the top of the plot. Let’s move the plot legend into a column at the right of the map. Create a new Legend icon and rename it to legright. Edit it, and set:
Legend Automatic Position |
Right |
Drop it into the Display Window to see the result.
We can also manually set the position of the legend by setting the following parameters, noting that the position of the legend is specified in cm from the bottom-left corner of the page, and that the default page size is A4 (29.7cm x 21cm):
Legend Box Mode |
Positional |
Legend Box X Position |
5 |
Legend Box Y Position |
2 |
Legend Box X Length |
20 |
Legend Box Y Length |
2 |
|
|
|
Automatic legend, top |
Automatic legend, right |
Positional Legend |
Note that the direction of the legend, by default, is computed automatically depending on the longest dimension of its positional box It can also be manually set in the Legend icon.
Annotation View
The Annotation View icon provides a container for user-defined text boxes. This view can also be used for layout purposes - if no user text is defined then an empty box will be created in the Display Window / paper sheet.
The user-defined text is provided by means of a Text Plotting icon.
Create a new Annotation View icon and visualise it - the Display Window will be empty.
Now create a new Text Plotting icon and rename it to note1. Edit it, setting the following parameters:
Text Line 1 |
Metview Training Course |
Text Mode |
Positional |
Text Box X Position |
10 |
Text Box Y Position |
10 |
Text Box X Length |
5 |
Text Box Y Length |
5 |
Text Border |
On |
Apply the changes and drag this icon into the Display Window.
Multiple Text Plotting icons can be placed in this View:
duplicate the note1 icon and rename it to note2.
customise it by changing for instance the font style and size (remember to re-define an appropriate text box).
drag it into the Display Window.
Extra work
Note
If you are attending the training course at ECMWF, please also consider the extra tasks in Analysis Views.
Create an A3 version of your plot layout
Copy your Display Window icon from the 3-plot exercise and set its paper size to A3 (page setup button).
Create a custom size plot, projection Mollweide
At global size, the Mollweide map is much wider than it is high. Create a new Display Window and experiment with a custom paper size until most of the white space has been removed from around the plot.
Customise the size of the map/view area
The automatic placement of the legend may not always be perfect for your particular plot. When we set the legend to be on the right-hand side of the map, there may not have been enough room for it. We can fix this by reducing the amount of space that the map takes up. Each view icon has a set of parameters to set the size and placement of the “subarea”. This is the area on the physical page occupied by the view. These parameters are defined in percentage of the page size. Try setting Subpage X Length to 80, then plot some shaded data and apply your legright icon to it to confirm that it now fits better.
Five Profiles
Create a layout with 5 Vertical Profile views, each showing a profile for a different location.