The QtiPlot Handbook
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# The Plot Menu

This menu is active only when a table is selected. These commands allow plotting data from the selected table. As a group, all of these commands create a new graph window which contains a single, empty layer. The newly created plot is drawn on this empty layer.

## Line

Plots the selected data columns using "Line" style. The command can also be activated by clicking on the icon of the Table toolbar. Once the plot is created, the drawing style of the data series can be customized with the Custom curves dialog.

## Scatter

Similar to the Line command except that the plot is drawn using "Scatter" style. The command can also be activated by clicking on the icon of the Table toolbar. Once the plot is created, the drawing style of the data series can be customized with the Custom curves dialog.

## Line+Symbol

Identical to the Line command except that the plot is drawn using "Line + Symbol" style. This command can also be activated by clicking on the icon of the Table toolbar. Once the plot is created, the drawing style of the data series can be customized with the Custom curves dialog.

## Special Line+Symbol ->

Selecting Special Line+Symbol opens up a sub-menu of additional commands for plotting specialized graphs consisting of lines and symbols.

### Vertical Drop Lines

Plots the selected data columns using "Vertical drop lines" style. Once the plot is created, the drawing style of the data series can be customized with the Custom curves dialog.

### Spline

Plots the selected data columns using "Spline" style. Once the plot is created, the drawing style of the data series can be customized with the Custom curves dialog.

### Vertical Steps

Plots the selected data columns using "Vertical Steps" style. Once the plot is created, the drawing style of the data series can be customized with the Custom curves dialog.

### Horizontal Steps

Plots the selected data columns using "Horizontal Steps" style. Once the plot is created, the drawing style of the data series can be customized with the Custom curves dialog.

### Double-Y

Creates a double Y axis graph. Requires a selection of at least two Y columns (or a range from at least two columns).

### Waterfall

Creates a new graph window containing a waterfall plot generated from data in the selected columns. Each column is drawn as a separate curve which is offset from the previous one in both X and Y, creating the so-called waterfall effect. The figure shown below is a simple example of a waterfall plot where each column is simply an attenuated version of the previous column.

### Zoom

Creates a new graph with 2 layers. The first is a standard plot layer which contains a curve for each selected Y column. The second is a special layer which has 2 components: 1) There is a standard plot layer that shows a portion of the first layer's surface in a magnified view; 2) There is a separate graphical window that can be sized and dragged around the first layer to specify the portion of that layer which is shown in the magnified view. The figure below shows a typical zoom plot.

## Columns

Plots the selected data columns using "Columns" style, that is vertical bars.

## Rows

Plots the selected data columns using "Rows" style.

## Special Bar/Column ->

Selecting Special Bar+Column opens up a sub-menu of commands for plotting specialized bar and column graphs.

### Stack Bar

The Stack Bar command plots a stack-bar for each selected row in the currently active table. They may be used to conveniently display cumulative data that changes over time, such as budgetary information. The stack-bars are drawn one above the other in a position determined by the X value of the corresponding row. Each stack-bar is composed of a set of joined segments. The widths of the segments are set by the Y values in the row and their relative positions correspond to the column order in the table. Each segment is plotted in a color corresponding to the column number of the Y value determining the segment's width. Colors, segment outlining, vertical separation of the stack-bars, and the axis values can all be customized. An example of a stack-bar plot is shown below, followed by the table that was used to generate the plot.

A stack-bar plot showing a hypothetical budgetary breakdown for a 5 year period. The data in the table shown below was used to generate this plot.

### Stack Column

The Stack Column command plots a stack-column for each selected row in the currently active table. It is essentially the same as the Stack Bar plot, but drawn as vertical stack-columns rather than horizontal stack-bars.

## Area

Plots the selected data columns using "Area" style.

## Pie

Creates a pseudo 3D Pie plot using the selected column in the active table window (only one column allowed).

## Vectors XYXY

Creates a vectors plot using the selected columns in the active table window. You must select four columns for this particular type of plot. The first two columns give the coordinates of the starting points of the vectors, the last two columns give the coordinates of the end points.

## Vectors XYAM

Creates a vectors plot using the selected columns in the active table window. You must select four columns for this particular type of plot. The first two columns give the coordinates of the starting points of the vectors, the last two columns give the angles (in radians) and magnitudes of the vectors.

## Statistical Graphs ->

Selecting the Statistical Graphs -> item opens up a sub-menu of commands for plotting various statistical graphs. Statistical plots do not give a direct drawing of the selected table data. However, a representation of the frequency distribution of the Y-values is plotted.

### Box Plot

Creates a box plot using the selected data columns in the active table window. This type of plot is used to give a graphical representation of some of the classical parameters of a frequency distribution, such as the mean, the min and max values, the position of the 95 and 5 percentiles, etc. The choice of the statistical parameters and the graphical parameters can be modified with the Custom curves dialog.

### Histogram

Creates a frequency histogram of the selected data columns in the active table window. The default binning uses 10 steps between the max and the min of Y-values. This can be modified with the Custom curves dialog.

Note that this command plots a frequency distribution that is computed from your data. If you want to draw a histogram directly from data values, use the Bars plot instead.

### Stacked Histogram

Creates vertically stacked layers displaying the histograms of the selected data columns in the active table window (one histogram per layer) See the Vertical 2 Layers command for more details.

### Stem and Leaf

Generates a stem-and-leaf tabular plot from the selected column in a new note window. Stem-and-Leaf plots are similar to histograms but are represented using rows of decimal digits. Like a histogram, data is binned, usually by taking the most significant digits (MSDs) as "stem" values which are listed in a column on the left. The least significant digit(s) from all values having identical MSDs are then listed to the right of each stem value. From a statistical point of view, this gives the appearance of a histogram but preserves the actual data values in the plot. When this command is executed, you will be given the opportunity to select/confirm the binning increment, which is given as a power of 10 and defaults to a power of 1 (that is, a binning increment of 10).

This figure shows a typical stem-and-leaf representation of 48 random data points which are roughly Gaussian (i.e., normally distributed) and uses the default binning increment of 10.

## Panel ->

Selecting the Plot -> Panel -> menu item opens a sub-menu of commands that can be used to quickly obtain some commonly used arrangements of multiple plots. Unlike other commands in this menu, the new graph window that is created may have more than one layer (as needed).

### Vertical 2 Layers

Creates 2 vertically stacked layers. The data columns selected in the active table window (one curve per layer) are plotted on these layers.

### Horizontal 2 Layers

Creates 2 horizontally stacked layers. The data columns selected in the active table window (one curve per layer) are plotted on these layers.

### 4 Layers

Creates 4 layers on a 2x2 grid. The data columns selected in the active table window (one curve per layer) are plotted on these layers.

### Stacked Layers

Creates a group of vertically stacked layers, one layer per Y-Coordinate column selected. Data columns selected in the active table window (one curve per layer) are plotted on these layers.

### Custom Layout...

Opens the Arrange Layers dialog which allows complete customization of the layer layout.

## Data -> Plot 3D ->

Selecting the Plot -> Plot 3D -> menu item opens a sub-menu of commands used to draw some common 3D plots of 2D data.

### Ribbons

Makes a 3D plot of the selected data column in the active table window (only one column allowed) using "Ribbon" style.

### Bars

Makes a 3D plot of the selected data column in the active table window (only one column allowed) using "3D Bars" style.

### Scatter

Makes a 3D plot of the selected data column in the active table window (only one column allowed) using "3D Dots" style. The 3D point symbol style can be changed via the 3D Plots Settings dialog.

With scatter plots, you can choose the kind of graphic item which is used to plot the data points. The example above is done with cross hairs, but you can also select points or cones. This can be done either with the corresponding icons of the 3D plot toolbar (respectively and for cross-hairs, dots and cones) or with the custom-curves dialog.

### Trajectory

Makes a 3D plot of the selected data column in the active table window (only one column allowed) using "3D Line" style. The line width and color may be changed via the 3D Plots Settings dialog.

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