EspressChart allows you to specify certain variables within text that allow for run time substitution based on certain values/objects in the chart. For example, if your chart uses a parameterized query as the data source, you could use the &paramInfo variable to display which parameter value(s) were selected at runtime.

Both the insert titles dialog and the add text dialog have a button marked Variables at the bottom. This will bring up a dialog with a list of variables you can use and it will allow you to select one to add to the title or to the text.

Variables Dialog

The following text variables are supported:

EspressChart allows you to overwrite a particular piece of text in a chart. This can be useful if the data source does not use particularly intuitive column names. Note that this feature will replace all instances of the text. For example, if you have a column chart without a series that displays a column name for both the X-axis label and the legend item, you cannot use text replacement to change only the label and not the legend item. The text replacement feature will also change only whole strings and not instances where there is a partial match.

To use text replacement, select Format → Text Properties. This will bring up a dialog allowing you to specify replaced text.

Text Properties Dialog

Please note that when making successive changes to the same text, the original text must be used. For example, assume you replaced the word “coffee” with “water”. Now if you want to change “water” to “soft drink” the text replacement should have the original text, which is “coffee” and then “soft drink” as the replacement. To remove any text replacement, simply replace the original string with itself. Hence, using the same example, you would replace “coffee” with “coffee”.

You can see a list of all the original text and the replacements by clicking on the List button. This will bring up a dialog listing all of the text replacement in the chart.

Replaced Text List

From this dialog you can select any of the replaced text and modify or undo the replacement by clicking the buttons at the bottom of the dialog.

EspressChart has the ability to automatically adjust the font size of the text in a chart as it is resized. This is useful if you're using the same chart template to produce a number of charts in different sizes. You can specify a ratio for the font size to adjust based on changes in the chart canvas. To specify a resize ratio, select Format → Text Properties.

Text Properties Dialog

The ratio dictates the relative percent that the font should resize in regards to the canvas. For example, say you resize a chart from 500 x 500 pixels to 250 x 250. With a resize ratio of 1 then text with 12 point font would decrease to 6 point, decreasing by the same percent as the canvas. However, with a resize ratio of 0.5 the font would decrease half as much as the canvas so our 12 point font would only decrease to 9 point.

Long labels or text in a chart can sometimes take up too much space in the chart plot, leaving little room for the actual chart. For situations like this, EspressChart offers a text cropping feature for chart text. Text that is longer than a user-supplied threshold will be truncated with “...”. The hint box for the chart will show the whole label. To specify text cropping, select Format → Text Properties.

Text Properties Dialog

To enable text cropping, check the Set Max Display Characters option and specify the maximum character length in the dialog. Any text longer than the specified number of characters will be truncated.

You can choose to display lines and points for all the data points in the chart for any two dimensional chart type. Note that some chart types already use this representation (i.e. line or scatter charts).

Column Chart with Lines and Points Defined

Line and point display is controlled by selecting Format → Line and Point, or click the Line and Point button on the toolbar. This will bring up a dialog presenting several options.

Line and Point Dialog

The first three options allow you to specify whether you would like to show lines, points, and a points border for the chart. For radar, scatter, and polar charts you also have the option of showing areas. For radar and polar charts the area option will fill in the areas enclosed by the data points. For scatter charts it will draw columns from the X axis to the data points. The remaining options allow you to customize the line and point displays for each element in the data series.

For each data series element, you can specify the point shape that you would like to use. You can also control the size of the points. The default point size is 0. You can specify point sizes of -1, -2, & -3 which represent sizes of 0.75, 0.5, and 0.25 respectively. At -3 (0.25), the point will be drawn as a dot regardless of the selected point shape.

For lines you can specify the line thickness, as well as customize a dash pattern. The dash pattern is created by specifying the number of filled pixels and the number of empty pixels (between 0 and 255). The line is then drawn by dividing into segments - the number of filled pixels followed by the number of empty pixels. Setting 0 for both will result in a solid line. Setting 255 for both will result in no line being drawn.

The last option allows you to change data point symbol border color to black or darker shade of symbol color.

Floating lines are free-form lines that can be arbitrarily added to any place on the chart canvas. Often floating lines are used to point to a specific element in a chart. To add a floating line select Insert → Line, or click the Insert Line button on the toolbar.

When you select this option, your mouse pointer will change to a cross. Click within the chart canvas where you would like the line to begin. Each additional click will add a point to the line, allowing you to add another segment. This way you can use floating lines to draw shapes as well. Once you have finished, right-click to stop drawing. The line will then be added.

Once a line has been placed on the canvas, it cannot be moved individually. It will move with the chart plot, like annotation text. To specify options for a floating line, first select it, and then select Format → Line and Point or click the Line and Point button on the toolbar. This will bring up a dialog allowing you to format various properties for the floating line.

Line and Point Dialog for Floating Lines

The dialog allows you to specify a standard line style or to create a custom dash pattern in the same manner as line and point formatting. You can also specify the line thickness in pixels. The checkboxes at the bottom of the dialog allow you to place an arrowhead at the start and/or end of the line, as well as fill the area enclosed by the line to create a solid shape.

Fixed horizontal or vertical lines are lines that are drawn on one of the chart axes. These lines can also be drawn on three-dimensional charts where they appear as planes. There are two types of fixed lines: constant lines and control lines. Constant lines are lines that are fixed to a certain value in an axis. Control lines are drawn based on computed values that allow you to spot data points that are outside of certain value ranges. To add either type of line to a chart, select Horz\Vert Line from the Insert menu. This will bring up a dialog showing the list of existing horizontal/vertical lines, allowing you to edit the selected line, remove the selected line, and/or create a new line.

Define Horizontal/Vertical Lines Dialog

Clicking on Insert or clicking on Edit when an existing line is selected, respectively, will bring up a dialog allowing you to configure the selected line.

Constant Line Dialog

For constant lines you need to specify a label for the line, as well as the numeric value to use for the line. Note that for the category axis, the data points start with 0.5. You can also specify the line thickness and whether the line is horizontal or vertical. The last two options allow you to add an item to the chart legend for the line and whether to display any annotation for the line.

For Gantt charts, there is one extra option called Current Date for Gantt Chart. If you choose this option, the Constant line value field will deactivate and the current date will be used as the line value (the line position will be updated every time you run the chart).

For radar charts, the horizontal/vertical option is disabled. Radar charts draw constant/control lines at the same point around all the chart axes (in a similar manner to the radar grid). In addition, for radar charts, an additional option named Circular Style is present. By default, lines in radar charts are drawn in a segmented fashion - straight lines connect the points on each axis. Selecting this option will draw the constant/control as a circle.

	Note
	If you have not specified any annotation for the line then none will appear if you select the last option. For more on adding annotation to a chart, please see Section 6.6.1 - Adding Text.

To add a control line, click on the Control Line tab in the dialog.

Control Line Dialog

For control lines you need to specify which series element you want to compute the value for (this option does not appear if no series is present) and how to compute the value. Options for control lines are average, minimum, maximum, and multiples of standard deviation.

After you have specified all of the options, the line will be added to the chart or the selected line will be changed, respectively. To edit any of the properties specified in the previous dialogs, you can select Insert → Horz/Vert Line again and select the line from the list. You can also double-click on the line that you want to modify.

You can change the appearance of fixed lines by first selecting the line and then selecting Format → Line and Point, or clicking the Line and Point icon on the toolbar. This will bring up a dialog allowing you to customize the line.

Line and Point Dialog for Fixed Lines

This dialog allows you to specify a standard line style or to create a custom dash pattern in the same manner as line and point formatting.

6.6.2.3.1. Multiple control lines for Stack Type Charts

For stack type chart, i.e., Stack Column, Stack Bar and Stack Area, we have API function:

...
newControlLine(int linetype, String label, int level); 
...

can draw control line with indicated stack level. For more information about this option, see Section 10.6.2.5 - Adding Multiple Control Lines to Stack Type Chart. If a stack column chart with the combo chart of stack area, the API can only works on the main axis data, i.e., stack column data; In this case, the API code cannot get the secondary value to draw control lines on stack area as combo.

You can also set the control line color with this API code. The following image shows the muliple control lines in different color, and display the meaning of them in the legend of the chart.

Stack Chart with Multiple Control Lines

A powerful feature of EspressChart is the ability to add trend lines to charts. Trend lines can help to show more details of a chart's data by exposing and highlighting certain trends.

Chart with Trend Lines

To add a trend line to a chart, select Insert → Trendline. This will bring up a dialog showing the list of existing trend lines, allowing you to edit the selected trend line, remove the selected trend line, and/or create a new trend line.

Trend Line Options Dialog

Clicking on Insert or clicking on Edit when an existing trend line is selected, respectively, will bring up a dialog allowing you to configure the selected trend line.

Define Trend Lines Dialog

In this dialog you can specify a label for the line, as well as what element of the data series to base the calculation on. The following types of trend lines are supported: a polynomial of any degree (please note that a linear trend line is a polynomial trend line of the 1st degree, i.e. the Polynomial curve order option has to be set to 1 ), a power, exponential, logarithmic, a moving average, an exponential moving average, an triangular moving average, cubic B-spline, and a normal distribution curve. For moving averages you will need to specify the average period and for a polynomial you will need to specify the curve order. You can also specify the thickness of the line and configure whether a label in legend and the attached text should be shown. In case the chart has data series, you can configure the trendline for a specific series.

After you have specified all of the options, the trend line will be added to the chart or the selected trend line will be changed, respectively. To edit any of the properties specified in the previous dialog, you can select 'TrendLine' from the Insert menu again, and select the line from the list. You can change the appearance of the trend line by first selecting it, and then selecting Format → Line and Point, or clicking the Line and Point button on the toolbar. This will bring up a dialog allowing you to customize the lines.

Line and Point Dialog for Trend Lines

This dialog allows you to create a custom dash pattern in the same manner as line and point formatting.

6.6.2.4.1. Normal Distribution Curve

A special type of trend line that allows you to draw a normal distribution curve for the data in the chart. In order to plot a normal distribution curve, the chart must either be a two-dimensional column or bar chart, it cannot have a data series, and the category should be numeric. Assuming these conditions are met, you can specify a normal distribution curve as one of the trend line options.

Chart with Normal Distribution Curve

Since the scale for the curve is usually different than the scale for the value axis, the curve is shown on a secondary axis. You can modify the scale by changing the scale for the secondary axis.

If you specify hyperlinks for charts, they will be active only when the chart is exported to Flash format*. For most image formats such as PNG, JPG, GIF, etc, an image map file containing information for the link will be automatically generated when you export the chart. You can insert the image and image map into an HTML file to view the image with clickable links.

	Note
	* For Flash export, when the user clicks on the hyperlink, there will likely be a warning message prompted by Flash saying that there was a potentially unsafe operation. You can turn this warning off by clicking on settings and adding the chart into the list of trusted locations.

Export Dialog