Titles, Legends, Axes

We saw in the section Creating a Line Graph how to add axis labels. Let’s now look at some other possible customisation of the graph. Specifically:-

(Before embarking on any of these exercises, ensure that the graph Tut_Line#1 (which was created in the previous section Creating a Line Graph) is currently opened within Deltagraph).

Adding/Modifying a Title

Let’s add a title to the Time/Distance graph Tut_Line#1. Carry out the following steps:-

First, make sure you’re in the right view. You should be in Chart View looking at a Deltagraph window containing the following:-

If not, select the appropriate page from the View Chart option in the View menu.

If it's not already visible, select Show Toolbox from the Draw menu. The drawing toolbox should appear, as follows (on the left in this case):-

Select the button by clicking on it. Then move the cursor onto the area immediately above the graph and, by dragging the cursor, create a rectangular area to contain the text for the title, as in the window below:-

Now:-

  1. Type in ‘Graph of Distance against Time’
  2. Click outside the rectangle containing the text (to de-select it), then click inside it (to re-select it).
  3. From the Deltagraph Text menu select Size and choose size 18.
  4. If necessary, adjust the size of the rectangle if the text isn’t held on one line. (You adjust the size of the rectangle by dragging an appropriate ‘handle’ at one of the four corners).

You should now have a window like the following:-

To modify the title, simply double-click on it. This puts you into edit mode and you can make whatever modifications you wish.

Positioning the Legend

Make sure that the graph is selected (it should have a ‘handle’ at each corner). If it isn’t selected, select it by clicking on it. Then click on the boundary surrounding the legend to select the legend:-

The legend can now be dragged around the screen (position the cursor on any white space within the legend and drag)to re-position it. Try placing it at the bottom right of the graph, as follows:-

Adjusting Axes Characteristics

When Deltagraph creates a graph/chart it applies certain defaults to the axes characteristics. Often these defaults will be perfectly adequate. However, if they are not suitable, it is possible to modify particular characteristics, as follows:-

X-axis

From the Chart menu select Axis then X Axis (first make sure that the chart is selected). The following dialog box should appear:-

The various attributes have the following meaning (Note: if you wish, you can skip over the following reference detail and go directly to a worked example by clicking here.):-

Axis Values

Parameters:- Meaning:-
Left Value Sets the value displayed on the left of the axis (if the ‘Auto’ box is ticked then Deltagraph will decide the value)
Right Value Sets the value displayed on the right of the axis (if the ‘Auto’ box is ticked then Deltagraph will decide the value)
Major Increment Sets the divisions for labels, major ticks, and major gridlines on the axis.
Minor Divisions Sets the divisions for minor ticks and gridlines on the axis.
Reverse Order Effect varies dependent upon chart type. In the case of an X-Y line graph, the effect is to interchange the Left and Right values, so that, for example, instead of the axis values running from 0 to 1 (left to right) they will run from 1 to 0 (left to right).

Axis Scaling

Parameters:- Meaning:-
Linear Scales the chart based on graduated values computed from the data in the Data View.
Automatic Deltagraph automatically calculates appropriate incremental divisions for the axis, as well as min/max values. (Note: if you enter new values for any/all of the attributes associated with the Axis Values options, then the automatic option no longer applies.
Logarithmic Scales the chart based on powers of 10. (Note: this option only applies to certain chart types and does not include: Stacked charts, Build-Up charts, Ternary charts, High charts, Contour Line charts, Contour Fill charts, or Grid Vector charts.
Range Allows you to specify start/end values for the axis that fall between the major increments while displaying the rest of the axis labels at normal increments. For example, normally if the left value were set to 0.05 with a major increment of 0.1, then the major increments would be labelled at 0.15, 0.25, 0.35, ... etc. However, if the Range option was set, then the labels would be 0.05, 0.1, 0.2, 0.3, ... etc.
Date/Time Scales the chart based on units of time measurement. (This is useful only if your data consists of dates or times).

Automatic Axis Scaling

Parameters:- Meaning:-
Standard The items within the Axis Values section will be changed so that zero is either on or between the left value and the right value. (Note that Automatic needs to be set in the Axis Scaling section for Standard to apply).
Floating Attempts to optimise any of the first values without requiring zero to lie between the extremes. (Note that Automatic needs to be set in the Axis Scaling section for Floating to apply).

Axis Attributes

If you click on the Axis Attributes button, the following dialog box appears:-

These attributes relate to Axis Placement, Axis Length, and Axis Offset. They have the following meanings:-

Axis Placement

Is used to determine the location of the axis. The available selections depend on the type of chart selected. In a chart consisting of two or more Value axes, this feature is particularly useful when plotting both positive and negative numbers. The parameters are:-

Parameters:- Meaning:-
Bottom Displays the selected Value axis at the bottom of the chart.
Top Displays the selected Value axis at the top of the chart.
On Value Controls the placement of the selected Value axis and its tick marks on the Category or Value axis grid (default is zero). The placement of the Value axis labels does not change. Simply click on the up or down direction arrows on the right of the On Value box to select the required value.

Axis Length

Determines the length of the Value axis and which measuring unit is used. Parameters are:-

Parameters:- Meaning:-
Units Click on the down arrow at the right of the box and select the required units from the resultant pop up menu:-

Length Type in a new length or use the up and down arrows at the right of the box to scroll the numbers in 36-point (half-inch) increments.
On Value Controls the placement of the selected Value axis and its tick marks on the Category or Value axis grid (default is zero). The placement of the Value axis labels does not change. Simply click on the up or down direction arrows at the left of the On Value box to select the required value.

Axis Offset

Is used to place an axis an ‘offset’ distance away from the chart. Parameters are:-

Parameters:- Meaning:-
Units Click on the down arrow at the right of the box and select the required units from the resultant pop up menu:-

Length Type in a offset length or use the up and down arrows at the right of the box to scroll the numbers in 36-point (half-inch) increments.

Y-Axis

From the Chart menu select Axis then Y Axis. The following dialog box should appear:-

Exactly the same characteristics apply to the Y-Axis as to the X-Axis. The only changes which apply are terminological (to reflect the fact that the Y-Axis is conventionally vertical, with the X-Axis being conventionally horizontal). They occur in the Axis Values section as follows:- "Bottom" instead of "Left"; "Top" instead of "Right"

Also, in the Axis Attributes... section:-

"Left" replaces "Bottom" and "Right" replaces "Top".

Example

We conclude this part of the tutorial by making some modifications to the current line graph Tut_Line#1, as follows:-

From the Chart menu choose Axis, then X Axis. The X Value Axis dialog box should appear. Set the Major Increment to 0.2 and Minor Divisions to 10, as below:-

Now, click on the Axis Attributes... button to display the Axis Attributes dialog box. Set Axis Placement to Top; Axis Length Units to Centimeters; Axis Length to 9.5; Axis Offset Units to Centimeters, and Axis Offset Length to 0.6, as follows:-

Now click on OK, and then click on OK again for the X Value Axis dialog box. The graph should now be redrawn, as follows :-

(Note: by clicking the Show button on the X Value Axis dialog box, you can see the effects of your axis attributes settings without committing to an altered graph; you only commit to a new graph when the OK button is clicked. At any time you can cancel the attribute settings by clicking the Cancel button).

Note that, because we have lengthened the X-Axis, the graph area now encroaches upon the Legend. Also, because we have placed the X-Axis at the top and located it 0.6 cm above the maximum y-value, the X-Axis and its label now encroach upon the graph title. Correct this as follows:-

The graph should now look something like:-

As a final exercise for this section, from the Chart menu choose Axis, then Y Axis. Click on the Axis Attributes... button on the Y Value Axis dialog box which should appear. In the resulting displayed attributes dialog box, set the required values as follows:-

Now click on OK, and then click on OK again for the Y Value Axis dialog box. The graph should now be redrawn. AS before, because we have changed the position of the Y-Axis, there will now be an overlap with the Legend. After increasing the chart area in a similar manner to before, and moving the Legend up to the top-right area, the revised graph looks something like:-

Finally, save the graph (select Save from the File menu) for use in the next section.

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