In this article, you will find a collection of useful tech tips for SigmaPlot. The tips are written and published by a tech expert from Systat, the producer of SigmaPlot.
Useful Tech Tips for SigmaPlot
Outliers in Box Plots
How are outliers handled in box plots? SigmaPlot provides two methods. Select them in Graph Properties > Box Plot Options.
Formatting Worksheet Areas
How do you format ranges in the data worksheet?
The Column Statistics Window
SigmaPlot automatically calculates a number of basic statistical values for all the data in your worksheet. and displays them in the Column Statistics. These values are updated whenever you change a value in your data worksheet.
How do I calculate a histogram of raw data based on the percent of total? Here is an example that generates the percentages from the raw data with a user-defined transform.
When graphing error bars and creating box plots, you can select the method of computing percentiles by either the Standard method or the Cleveland method.
Export worksheet data as formatted (decimal places) to the clipboard
SigmaPlot can copy worksheet data to the clipboard a) in full precision, or b) with the number of decimal places which are set in the worksheet.
Graphing raw and cumulated values
You can display raw and cumulated values in the same graph. Here are the steps to create this example.
How to re-assign data to a plot?
You can change the data assignment for a plot from the Graph Properties Dialog. Select the "Plot" line in the tree on the left, and click on the "Graph Wizard" button.
Align Objects on the Graph Page
Did you know... that you can align objects on the graph page relative to each other, or relative to the graph page?
Unindex One-way 2 Columns
In the Statistical Transforms, there are functions to Index/Unindex variables in a worksheet.
The lookup transform function assigns index values to the values in a worksheet column A, corresponding to another column of interval or class limits.
Point Plots and Dot Plots
Point plots and dot plots are special versions of SigmaPlot's Scatter/Line and Scatter plots. The main difference is the way they assign worksheet columns to the symbols of the graph.
Adding the Close All button to the Quick Access Toolbar
The Close All button closes all open page windows, worksheet, report etc. with a single click.
Freeze Panes in the SigmaPlot worksheet: Columns, Rows, and Sections
You can freeze panes to keep rows and columns visible as you scroll through the worksheet.
How to use the "interpolate" transform function
The "interpolate" transform function creates interpolated y values for an xy data table.
Error Bar Directions
You can set the direction of error bars in SigmaPlot’s Graph Properties dialog: Plot > Error Bars > Direction.
SigmaPlot Statistics Result Graphs
When you run a statistical test in SigmaPlot, it is possible to right-click on the report page and create a result graph that is appropriate for that test. These graphs can be modified by the Graph Properties, or by the mini toolbars, but the data is not directly available, so if, for example, you want to reorder the elements of a graph, it is not possible to change the order of the data.
Moving a network license to another machine
You can migrate your SigmaPlot 13 network license to another machine without requesting a new license file.
The Publication Assistant checks if your graph matches the requirements of the journal or other media where you want to publish your research.
Rearranging Notebook Items
You can rearrange the order of notebook items by dragging them with the mouse: worksheets, graph pages etc., and also sections.
Interpolation issues with Mesh and Contour graphs
When the X and Y values are not so spaced, SigmaPlot interpolates values, and can give unexpected results. This article covers other options for generating data for these graphs.
A category plot displays grouped data (scatter, line/scatter, bar graph). The data can be XY pairs, Many X, or Many Y. (For Many X or Y, the corresponding Y or X values are auto-numbered).
Global Graph Attribute Changes
You can make global text and other attribute changes by selecting a graph, or pressing Ctrl+A to select everything on a page, then using the Tools and Text ribbons on the Graph Page tab.
Parallel Lines Analysis Macro
This macro tests XY data pairs for equality of slopes. If the slopes are found to be insignificantly different then it tests for the equality of y-intercepts. A pooled slope (intercept) is computed if the individual slopes (intercepts) are insignificantly different
How to create a data table from an equation
How to create a data table from an equation to present, export the values, and plot the data. We will look at these features in SigmaPlot for linear regression, using the regression Wizard, plot equation and with user-defined transforms.
Editing a Graph Gallery Graph
Did you know that you can easily modify the graphs in the Graph Gallery with a right-click > Edit?
The Graph Gallery – on the left side of the screen, below the Notebook Manager – holds graphs which you can easily use as a model for further graph creation. Turn it on or off in the Home ribbon > Navigate > Gallery pane.
There are several graphs in the Gallery when you have installed SigmaPlot. You can easily add graphs by dragging them from the graph page to the Gallery pane. The graph becomes an icon in the Gallery, its title becomes the caption. To create a new graph from this model, double-click on the icon, and follow the Create Graph dialogue. To modify one of the Gallery graphs, just right-click on it, and select Edit. It opens on a new graph page. You can modify it in the Graph Properties, and when you save it, it is updated in the Graph Gallery.
Flexible Legends in SigmaPlot 13
Prior to version 13, if you wanted to rearrange the legends of a SigmaPlot graph, it was necessary to ungroup them, which broke the link between the legend and the graph properties. Now, it is possible to rearrange the legend items in respect to one another, alter the number of rows of the legends, or use direct labelling of graph items, with the legends still being bound to the graph properties.
Creating a Candlestick Graph
The Candlestick graph looks similar to a box plot, but without capped error bars, and with no median line.
Histogram with Kernel Density Macro
In addition to the histogram options covered in our last Tech Tips, SigmaPlot 13, now provides the macro Histogram Plus Kernel Density. This is available in the Toolbox ribbon, Macros.
Histograms (bar graphs of tabulated frequencies) can be created in SigmaPlot from the Graph Analysis section of the Analysis ribbon or as a bar graph from the Create Graph ribbon.
X Direction Confidence Intervals - Interpolation
When you fit a data set in SigmaPlot's Regression Wizard, you can display confidence and prediction bands intervals for the fitted curve (Y) and add the values to the worksheet.
Merge Columns Macro
This macro combines two columns (such as dates and times) to a single column in the first empty column.
SigmaPlot selects the axis scale type for new plots based on the data type in the first row of the worksheet. This way, plots can happen to be created with a category axis instead of the intended numerical axis, making the graph look "wrong".
In this XY line graph, the line color represents the grouped values of a third variable.
Statistical Transforms — Center and Normalize
With SigmaPlot's Statistical Transforms, you can centre and normalize your data.
Floating Bar Graph
In this horizontal bar graph, "colors from columns" are used to display alternating states of one variable in stacked bars.
Plot and Solve Equations
With SigmaPlot's equation plotter and solver, you can plot curves of data from user-defined equations. You can also evaluate equations for data points or data ranges, and solve them for a data range.
The Color Transition Values Macro
This macro creates a column of colors changing smoothly in colors as the data changes from its minimum value to its maximum value and employs this gradient to color e.g. the symbols in a scatter plot.
Bubble plot – adjusting the bubble sizes
Bubble plots are XY scatter plots that use symbols to represent not only XY locations, but also a third dimension represented by the size of the symbol.
Multiple axes can be useful to show the data in the graph in different scales.
Splitting groups of data from one column into multiple columns (unindex)
To split a data column with data from different groups (identified by a group of "factor" value in a second column), you can use the "By Group Data Split" Macro or the Statistical Transform "Unindex > One Way".
Axis breaks in a graph a with customized axis ("from column")
When you have a graph with a customized axis ("tick labels from column"), and you add an axis break to this axis, the display of the tick labels will be wrong if the break spans one or more ticks"
Normal Distribution Comparison-Macro
SigmaPlot ships with many macros that are not exposed in the toolbar, but are available under the Macros button. One that can be particularly useful is the Normal Distribution Comparisons, which is a preliminary reliability evaluation.
Text as symbols, and labels added to symbols
You can label graphs using text as symbols in a plot, giving more flexibility than using the label symbols macro.
UI Panels: Turn off and on UI elements
"The Status Bar with the Zoom Tools is gone. How do I get it back?"
Rearranging worksheet data: From 1 to many columns
With SigmaPlots built-in User-Defined Transform language, you can transform, calculate, and rearrange data. Here is an example which shows how you can quickly rearrange input data from 1 column into many columns.
Arranging and aligning Graphs (and other Objects on the Graph Page)
There are several methods to arrange and align multiple graphs/objects on the graph page.
Quick Transforms with Automatic Update
With SigmaPlot's Quick Transforms (Analysis > Quick Transforms, or the Shift-F10 keys), you can enter a one-line transform equation.
The "Rank and Percentile" macro
This macro computes ranks and cumulative percentages for a specified data column, and also reports the values for specified percentiles.
SigmaPlot user files, where are they, what are they?
SigmaPlot provides a number of user-customizable files where preferences are stored. These can be found in "My Documents\SigmaPlot\SPW12" in Windows XP and "Documents\SigmaPlot\SPW12" on Vista, Windows 7 and Windows 8.
Border plots show the individual distribution of variables along the axes of a 2D graph.
Boxplots from statistical parameters
You can create box plots from (calculated) statistical values: 1st, 2nd and 3rd quartile = 25th, 50th, and 75th percentile (see the Online Help on Box Plots).
Using Column Titles as Tick Labels, with a User-Defined Transform
You have a worksheet with column titles for your data, e.g. “Group A”, “Group B”, “Group C”, and you want the column titles displayed as X-axis tick labels.
File formats and import stepsFile formats and import steps
Text data can be imported into the SigmaPlot worksheet from the Worksheet ribbon > Import File. This opens the Import File dialogue, with several text data file types:
Decimal sign in SigmaPlot
Data in the SigmaPlot worksheet can be text, numbers, or dates. The text is left-justified in the cell, numbers are right-justified.
Utilities for decimal sign conversion
On our website, we have 2 small utilities for comma/point decimal sign conversion, one for each direction. For bigger data files, these should be faster than using an editor. Also, the point-to-comma version is aware that the comma is used as a field separator in CSV files ("comma separated values"): points are changed to commas, commas are changed to semicolons.
Stacked bar graph with error bars
Question: I want to create a stacked bar graph that has error bars for each section. I can make a stacked bar graph but can't work out how to add error bars to it. Is this possible to do?
An Arrhenius graph "displays the logarithm of kinetic constants (ln(k), ordinate axis) plotted against inverse temperature". (en.wikipedia.org/wiki/Arrhenius_plot).