This option lets you normalize heights across each level of the hierarchy (or across all levels) of bars, node bases, and disks. Normalizing the heights determines the maximum value of the height variable; it normalizes all values relative to that height. Thus, if the maximum value is 30.0, and the maximum bar height was set to 1.0 (in arbitrary units), a value of 15.0 would be mapped to a value of 0.5.

Normalizing across each level independently normalizes each level of the hierarchy. This option is most useful if data has been summed up the hierarchy, and prevents the top level of the hierarchy from dwarfing items at the lowest level. Normalizing across all levels normalizes everything together, regardless of the level in the hierarchy. If neither box is checked for bars, no normalization takes place.

Node Bases are normalized independently of Bars. If no boxes are checked, the same normalization method used for bars is used for node bases, although the values are normalized independently.

If disks are present and normalize with bars is checked, the disks are normalized in conjunction with the bars: a disk and a bar representing the same value have the same height. If one of the other normalize boxes is checked in the Disks column, disks are normalized independently of the bars: the highest disk and the tallest bar have the same height, regardless of the actual values represented by them.

This option lets you specify the height of the tallest bars and node bases. The default is 1.0 (in arbitrary units). If after looking at the view, you see that the heights are too low or too high, use this field to adjust them. For example, entering 2 in the field causes all bars to be doubled in height; entering .5 makes all bars half as big.

If normalization was specified, this value represents the height of the tallest bar or base. If normalization was not specified, all values are scaled by this amount. The latter can be useful when comparing views of two different datasets.

This option lets you filter out nodes containing only short bars. First, the tallest bar in the scene is calculated (if heights are normalized by level, then the tallest bar in each level). Then only those nodes that contain at least one bar that is the appropriate percentage of the tallest bar are shown. For example, if you enter 5% in this field, then only those nodes containing at least one bar that is at least 5% of the height of the tallest bar are shown. (Also shown are ancestors of such bars). This option is intended as a coarse way to filter out small, uninteresting nodes. It is not intended as an exact mechanism of identifying specific nodes of a certain value. Use of this option can accelerate the rendering of slow, complex scenes, or reduce clutter resulting from many bars near zero height.

Although small nodes are filtered out, they are nonetheless counted in any cumulation up the hierarchy.

By default, the height of the bars of the parent node is the sum of the height of all the bars of the children; however, these heights can be average, max, min, count, or any of the values that appear. This aggregation can be used for the values of the bar heights, base heights, and disk heights.

This set of options lets you

To use these Colors options, you must have mapped a column to the *Color - Bar, *Color - Disk, or *Color - Base requirements of the Data Destination panel. See “Choosing Colors” and “Using the Color Browser” in Chapter 3 for a more detailed explanation of how to choose and change colors.

Color list to use lets you specify the color list using the + button next to the color list label. This brings up a color editor that lets you specify a color to be added to the list.

Kind of mapping lets you specify whether the color change that is shown in the graphic display is Continuous or Discrete. If you choose Continuous, the color values (of the bars, node bases, or disks) shift gradually between the colors entered in the Color list to use field as a function of the values that are mapped to those colors in the Color mapping field. If you choose Discrete, the colors change only at the specified boundaries.

Color mapping lets you specify values to which the colors are mapped.

If you

then the display shows all bars (or node bases or disks) with values of less than 100 in red, and all those with values greater than or equal to 100 in green.

If you

then the display shows all bars (or node bases or disks) with values less than or equal to 0 as completely red, those as greater than or equal to 100 as completely green, and those between 0 and 100 as shadings from red to green.

By default, the values of the colors of the bars of the parent node are the sum of the values of all the bars of the children; however, these colors can be average, max, min, or any of the values that appear. This aggregation can be used for the values of the bar colors, base node colors, and disk colors.

This option lets you automatically color the bars by their key value. This option is ignored if another coloring was specified. If you specify no color list, or specify insufficient colors, additional colors are chosen at random. If extra colors are specified, they are ignored.

By default, this option places all bars across one row. This option allows changing the number of rows or columns. If neither rows nor columns are selected, or the number is set to 0, then neither rows nor columns are fixed, and the closest approximation to a square is displayed.

This option lets you type in any message you want. The message statement specifies the message displayed when the pointer is moved over an object or when an object is selected. By default, the same message is used for the base as for the bars. If no message is specified, a default message containing the names and values of all the columns is used.

The format of the message must match the type of data being used:

For a detailed description of the message field, see “Message Statements” in Appendix B.

These options let you type in a UNIX command that is executed when double-clicking on a bar or base. If only the Execute field is filled in, it applies to both bars and bases. If both are filled in, Execute applies to bars, and Base Execute applies to bases. The format is similar to the message statement. If no execute statement appears, double-clicking has no effect.

For a detailed description of the Execute field, see “The Execute Statement” in Appendix B.

You can specify either one or two colors. If only one color is specified, the sky is solid. If two colors are specified, the sky is shaded between the colors. When specifying two colors, the first color is for the top of the sky, the second for the bottom.

You can specify either one or two colors. If only one color is specified, the ground is solid. If two colors are specified, the ground is shaded between the colors. For the ground, the first color is for the far horizon, the second is for the near ground.

You can specify the color of the labels on the front of the bases.

You can specify the color of the labels on the front of the bars.

You can specify the color of the lines connecting the bases.

If you select the Sort by Key checkbox, the nodes in the display are in sorted order. The menu next to the checkbox lets you specify whether to sort in ascending or descending order.

If, after you have made changes to the Tool Options dialog box, you want to reset the values of all options to their default values, click the Reset Options button.

Once you have finished making changes to the Tool Options dialog box, click OK to return to the Tool Manager's main screen.

Select Overview in the Show menu to bring up a new window with an overhead view of the complete hierarchy (Figure 5-14). If you want the Overview to be brought up automatically each time the scene is viewed, set the Overview option in the configuration file (see “Overview”).

The “X” in the Overview window shows your current location. The Overview helps you keep track of your location and viewpoint in the entire scene. It can also help you quickly go to a specific node.

To select an object in the Overview and have the main view zoom to it, left-click that object. This is similar to left-clicking the object in the main view. Middle-clicking anywhere in the overview zooms your viewpoint to that location, even if no object is at that point.

Select Search in the Show menu to bring up a dialog box that lets you specify criteria to search for objects (Figure 5-15).

Once the search is complete, yellow spotlights highlight objects matching the search criteria (see Figure 5-16). To display information about an object under a yellow spotlight, move the pointer over that spotlight; the information appears in the upper left corner, under the label Pointer is over:. To select and zoom to an object under a yellow spotlight, left-click the spotlight; if you press the Ctrl key while clicking, zooming does not occur.

To specify whether a search is case-sensitive, click the Ignore Case In Searches checkbox, at the top of the Search panel. For example, if this toggle is on (a check mark appears on that button), the string “hello” is the same as “HellO.”

To the right of the case sensitivity checkbox is another, labeled Treat Nulls as Zeros. If this checkbox is off (the default), comparisons involving nulls cannot return TRUE in a search. If the it is on, nulls are treated as equal to zero.

Below the case-sensitivity checkbox are controls that let you specify the parts of the hierarchy to be searched. By default, the whole hierarchy is searched. To limit the levels searched, select a relational operator (such as <=) from the option menu that lets you specify the operand for the level. Then use the slider to select the level to be searched. Level 0 is the root of the hierarchy, level 1 is the level below that, and so forth. To search the root and the two levels below that, for example, choose <= 2.

Checkboxes also let you choose whether to search the bars or the bases.

When searching through bars, the default is that all bars are searched. To search only a specific list of bars, you must select them. The Set All button turns on all bars; this is useful if most of the bars are to be searched, and only a few are to be turned off. The Clear button turns off all bars. If no bar is selected, the bar list is ignored, and all bars are searched.

Below the panel for bar labels is a Hierarchy field that lets you specify nodes to search (Figure 5-17). Below the Hierarchy field are fields that let you specify search criteria for individual columns (defined in the Current Columns: window of the Tool Manager's Table Processing pane, see “Selecting the Tree Visualizer Tool”).

To search for numeric values, enter the value, and select a relational operation (=, !=, >, <, >=, <=). To search for alphanumeric values, enter the string for which you want to search. You can use any of three types of string comparisons:

In some cases (usually associated with binning in the Tool Manager), an option menu of values appears, instead of a text field. To ignore that variable, select Ignored in the Option menu. You can use relational operators (such as >=) with these options. This means that the specified value as well as subsequent ones are selected.

In addition to numeric and string comparison operations, you can specify Is Null, which is true if the value is null.

To the right of each search field is an additional option menu that lets you specify “And” or “Or” options. For example, you could specify “sales > 20 And < 40.” You can have any number of And or Or clauses for a given column, but cannot mix And and Or in a single column.

Note that if different levels of the hierarchy are keyed by different types of data (for example, the top level is selected by strings, while the second level is selected by integers), then the “Hierarchy” search field is treated as a string and provides string operations, not number operations.

If the Ignore Case In Searches checkbox is checked, the comparisons of all string searches are case-insensitive.

Six buttons are placed across the bottom of the Search panel:

The Filter panel filters out selected information, thus fine-tuning the displayed hierarchy. You can use the Filter panel to emphasize specific information, or to shrink the amount of data for better performance. Figure 5-18 shows a sample Filter panel.

To specify whether a filter is case-sensitive, click the Ignore Case In Filter checkbox, at the top of the Filter panel. For example, if this toggle is on (a check mark appears on that button), the string “hello” is the same as “HellO.”

To the right of the case sensitivity checkbox is another, labeled Treat Nulls as Zeros. If this checkbox is off (the default), comparisons involving nulls cannot return TRUE in a filter. If the it is on, nulls are treated as equal to zero.

Below the case-sensitivity checkbox are controls that let you specify the parts of the hierarchy to be filtered. By default, the whole hierarchy is filtered. To limit the levels filtered, select a relational operator (such as <=) from the option menu that lets you specify the operand for the level. Then use the slider to select the level to be filtered. Level 0 is the root of the hierarchy, level 1 is the level below that, and so forth. To filter the root and the two levels below that, for example, choose <= 2.

Checkboxes also let you choose whether to filter the bars or bases.

When filtering bars, the default is that all bars are filtered. To filter only a specific list of bars, you must select them. The Set All button turns on all bars; this is useful if most of the bars are to be filtered, and only a few are to be turned off. The Clear button turns off all bars. If no bar is selected, the bar list is ignored.

Filtering bars does not affect the information in the base, which continues to include the summary of all bars.

Below the panel for bar labels is a Hierarchy field, which lets you specify nodes to filter. Below the Hierarchy field are fields that let you specify filter criteria for individual columns (defined in the Current Columns: window of the Tool Manager's Table Processing pane, see “Selecting the Tree Visualizer Tool”).

To filter for numeric values, enter the value, and select a relational operation (=, !=, >, <, >=, <=). To filter for alphanumeric values, enter the string for which you want to filter. You can use any of three types of string comparisons:

In some cases (usually associated with binning in the Tool Manager), an option menu of values appears, instead of a text field. To ignore that variable, select Ignored in the Option menu. You can use relational operators (such as >=) with these options. This means that the specified value as well as subsequent ones are selected.

In addition to numeric and string comparison operations, you can specify Is Null, which is true if the value is null.

To the right of each filter field is an additional option menu that lets you specify “And” or “Or” options. For example, you could specify “sales > 20 And < 40.” You can have any number of And or Or clauses for a given column, but cannot mix And and Or in a single column.

Note that if different levels of the hierarchy are keyed by different types of data (for example, the top level is selected by strings, while the second level is selected by integers), then the “Hierarchy” filter field is treated as a string and provides string operations, not number operations.

If the Ignore Case In Filters checkbox is checked, the comparisons of all string filters are case-insensitive.

If a node does not meet the filter criteria, has no bars that meet the criteria, and has no children that meet the criteria, the node is not shown. There can be, however, cases in which a specific object meets the filter criteria, but its ancestors up the tree do not. Also, other bars in the same node might not meet the criteria. Since position is important in interpreting context, it might not be good to eliminate those bars. Consequently, you are given an option of selecting one of three radio buttons that control how these objects should be drawn: Solid, Outline, and Hidden. Note, however, that if objects are drawn in a less solid form due to the Display Zeros or Display Null menu, they are displayed appropriately. For example, if Nulls are to be hidden, they are always hidden, regardless of the filter criteria.

The exception to this is when filtering to specific bars. In such a case, the other bars are eliminated and don't take up space, regardless of the radio button settings.

The Height Filter slider lets you filter out those nodes containing only short bars. The size of a value is shown as a percentage of the maximum height. First, the tallest bar in the scene is calculated (if heights are normalized by level, then the tallest bar in each level). Then only those nodes that contain at least one bar that is the appropriate percentage of the tallest bar are shown.

For example, if you enter 5% in this field, then only those nodes containing at least one bar that is at least 5% of the height of the tallest bar are shown. (Also shown are ancestors of such bars). This option is intended as a coarse way to filter out small, uninteresting nodes. It is not intended as an exact mechanism of identifying specific nodes of a certain value; use the search panel for that purpose. Use of this option can accelerate the rendering of slow, complex scenes, or reduce clutter resulting from many bars near zero height. You can also set this filtering option in the configuration file by using the Height Filter command.

Although small nodes are filtered out, they are nonetheless counted in any cumulation up the hierarchy.

The Depth slider, which is under the Height Filter slider, lets you display the hierarchy so that only a given number of levels are displayed at any given time. When you are at the top of the hierarchy, only the number of hierarchical levels specified by the slider is seen. The nodes in the rows are arranged to optimize their visibility. When navigating to nodes lower in the hierarchy, additional rows are made visible automatically. The nodes above them automatically adjust their locations to accommodate the newly added nodes; thus, some nodes might seem to move. Note that the overview shows all nodes in the hierarchy, not just the top nodes; thus, the layout of the overview might not match the layout of the main view. The X in the overview approximates the corresponding location in the main view; there is no exact mapping between the two layouts.

The Marks panel, from the Tree Visualizer's Show Pulldown Menu (Figure 5-13,) lets you name and store important locations (viewpoints) so that you can easily and quickly return to them (see Figure 5-19). The location is stored relative to the currently selected object. If no object is selected, the absolute location is recorded.

All marks can be indicated by colored flags in the main view. If the mark represents a selected object, the flag is placed on that object. If it represents an absolute position, the flag is placed at that position. To go to the mark, click the flag. All flags can be turned on and off using the Mark Flags menu entry in the Display menu. (See Mark Flags in “The Display Menu”).

Figure 5-21 shows a sample main window with flags representing the created marks.

The file storing the marks information has the same name as the configuration file, with a .marks suffix appended. Whenever a mark is changed, all marks are saved to that file. If all marks are deleted, the .marks file is removed. If mark changes cannot be saved (because of a permission error, for instance), a warning appears; this warning is not repeated when subsequent mark changes are attempted.