Data Series

Each plot will have one or more 'series' which organize the data values. Each series element has a number of properties. The element will have a Style tab with which the style of the line and point markers, or the area and outline can be set. Each series element will have a Data tab in which the name of the series, the values used for the series and any labels associated with these values can be entered. The data values will generally be entered as references to cells on a worksheet which will allow the plots to be automatically altered when the values in the worksheet change. The series may also have one or more Error tabs in which error values can be associated to the data value of each element in the series.

10.4.6.1. Series line style

Series in line plots, in some radar plots and in scatter plots will have a style tab in which the graphical style of the lines and point markers can be established.

Figure 10-31The configurable properties of a line style.

The properties of a single value data series include an optional name, a required list of values and an optional list of labels. The name, in this case, is a reference to cell D7 in the first worksheet. The values are the contents of the cells in the range E7:I7. The labels are the contents of the cells in the range E6:I6. Note that there are as many cells in the labels range as in the values range.

The Line properties include the line color and size. The color can be altered in the standard way using the drop down color chooser. The width of the line can be changed with the spin box. A line size of '-1' means that the line will not be plotted.

The Marker properties determine the style of the graphical symbol which will be plotted for each data value. The first drop down box allows the user to choose between a number of different symbols. The blank symbol indicates that no symbol will be plotted where the data value would be. Each shape will have a fill color, and an outline with both a color and a size. The colors can be changed by clicking on the drop down box and picking one of the given colors or using the color picker to select a new color. The size of the outline can be altered by clicking in the text area and editing the value or by using the spin arrows to increase or decrease the size.

10.4.6.2. Series filled style

Series in bubble plots, area plots, bar plots, column plots, filled radar plots, and ring plots will have a Style with fill and outline properties. These properties are the same as those presented for background panels in Section 10.4.1 ― Background Panels: Graphs, Charts, Grids and are changed in the same way.

Figure 10-32The configurable properties of a filled style.

The Fill properties will determine the character of the inside of the area. The fill type can be none, pattern, gradient, or image, in the same way as the fill of background panels. If images are used for the background, the whole image will be shown and it will be scaled to the size of the area.

The Outline properties will determine the size of the linear element that surrounds the area. The color and size of this outline element can be altered.

10.4.6.3. Series data: single values

The Data tab allows the user to configure the data contents of the series. Some of these data contents are optional, as is indicated by the parentheses around the label. At the minimum one set of numerical quantities will be required.

The entry boxes in the Data tab can be filled in several ways. The data can be a static value or array such as a sting literal, "SeriesName", or a group of values, {12.05, 73.02, 128.89}. Note that the separator between elements in the array will depend on the locale since the glyph between whole numbers and decimal fractions differs around the world. Alternatively, the value of an entry box can be the reference to a cell or to a range. This reference can either be typed into the entry box or can be entered by clicking in the entry box text area and then selecting the range on the worksheet. Finally, the value in the entry box can be an expression, such as sin({120, 982, 140}).

Single series involve the simplest data. They may have an overall name, must have a list of values, and may have a list of names, with as many names as there are numbers in the values list, which will act as category names. For plot types with more than one single list series, the label names will be shared between all the series.

Figure 10-33The configurable properties of single value data series.

The Name property is a single string which will give a tag to the series itself. A name is not required. This name will be used in the Graph Guru to name the series and may be used in a chart legend to describe the series.

The Values property must contain a list of numeric quantities. A list of values is required. The values can be described either directly as a static array, described through a reference to a cell range with numeric values, or described through an expression which results in the list of quantities.

The Labels property describes the names of the categories. This property is not required. must be a list of text elements, with as many elements as there are quantities in the list of values. These elements will provide the elements in the legend for pie and ring plots. For line, area, bar and column plots, the labels will provide the category names for the axis with categories.

The Show in Legend property determines if this series will be shown in the legend if a legend is added to the chart. It is sometimes useful to exclude certain series from the legend. If the box is checked, the series will be included in any legend displayed in the chart; if the box is not checked, the series will not be displayed in the legend. The box can be unchecked by placing the mouse pointer over the box and clicking with the primary mouse button.

10.4.6.4. Series data: X and Y values

Series with dual data values allow plots to be constructed in which one value is plotted against the other. XY scatter plots require this type of data.

Figure 10-34The configurable properties of dual value data series.

Dual data series require two sets of values, an X list and a Y list.

The Name property is a single text element that will name the series in the graph guru and in any legend in the chart.

The X property is a list of quantitative values that will provide the horizontal positioning of each element. This list is required.

The Y property is a list of quantitative values that will provide the vertical positioning of each element. This list is required and must have the same number of elements as the list of X values.

10.4.6.5. Series data: bubble values

Bubble series are simple extensions of the XY series to include a third data value, often called W, which will determine the size of the bubble.

Figure 10-35The configurable properties of bubble data series.

The Name property is a single text element that will name the series in the graph guru and in any legend in the chart.

The X property is a list of quantitative values that will provide the horizontal positioning of each element. This list is required.

The Y property is a list of quantitative values that will provide the vertical positioning of each element. This list is required and must have the same number of elements as the list of X values.

The Bubble property is a list of quantitative values that will provide the size of the bubbles associated to each element. This list is required and must have the same number of elements as the lists of X and of Y values.

10.4.6.6. Series error values

Several plot types allow the plotting of error values using whisker plots. The series in these plot types will have extra tabs allowing the whisker positions to be listed. Line, bar, column and area plots allow an error plot to bracket the plotted quantitative value in the direction of the quantitative axis. XY scatter plots and bubble plots allow whiskers in both directions.

Figure 10-36The configurable properties of data series error values.

The Error Category includes several different categories which can be selected by clicking on the drop down box and dragging the mouse pointer onto the appropriate entry. If the error category is set to "none", no error bars will be plotted. If the category is set to "absolute" the values in the error lists will be considered to be in the same units as the axis. If the category is set to "relative", the values in the error list are assumed to be a fraction of the total of each value. If the category is set to "percent", the values in the error list are assumed to be 1/100 th of the fraction of the total of each value. Note that if the cells in the worksheet are already set to the percent format, they should be incorporated as "relative" errors.

The Style properties alter the appearance of the error whiskers. The Display property can be used to prevent the display of any whiskers, to allow only upper or lower whiskers, or to display both. The Width property alters the width of the outer marker of the whisker. The Line width property alters the size of the whiskers. The color box selects the color of the line used to draw the whiskers.

The Values properties describe the lists of quantitative values which will be used for the whiskers. These lists are required if an error is to be displayed and the lists must have as many elements as were in the list of data "Values". The positive (+) list quantifies either only the upper error values if the lower values are not displayed or the negative list is defined. The positive list can also be used for both error values if the errors are symmetrical. The negative (-) list quantifies the lower whisker.