Help Manual

Contents






Sigma Magic Help Version 15

Heat Map

Overview

A heat map is a graphical representation of data where values are depicted by color. Heat maps make it easy to visualize complex data and understand it at a glance. By better visualizing the data we are working with, we can make the data sets comprehensible and actionable. A heat map uses colors the way a bar graph uses height and width. For example, you are looking at a web page and want to know which areas get the most attention; a heat map could be a visual way to display the information with the most-visited parts of the website shown in red color and the other areas shown in blue or green color. By understanding where your visitors are looking most of the time, you can use that portion to display the more important content information.

To add the Heat Map tool to your worksheet, click on Analytics and then select Graphs > Heat Map.

Inputs

Click on Analysis Setup to open the menu options for this tool. A sample screenshot of the menu is shown below: Heat Map Menu 1
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Dendrogram: Specify if you would like to superimpose a dendrogram on your heat map.
OptionDescription
NoneDo not display any dendrogram on the heat map.
ColumnOnly shows the dendrogram for the column variable.
RowOnly shows the dendrogram on the row variable.
BothShows the dendrogram on both the row and column variables.
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Scale Data: Specify if you want to scale your data before the heat map is created.
OptionDescription
NoneDo not scale the input data. Use the data as provided.
ColumnScale the column vector so that it has unit variance.
RowScale the row vector so that it has unit variance.
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Colors: Specify the colors to be used for the heat map. Example: cm.colors(256) or terrain.colors(256) etc.
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Title: Specify the title to use for your heat map.
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X Label: Specify the label to use for your X-axis.
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Y Label: Specify the label to use for your Y-axis.
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Additional Options: This field is optional. You can specify any additional options for the R software program directly by typing it here.
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Help Button: Click on the Help Button to view the help documentation for this tool.
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Cancel Button: Click on the Cancel Button to discard your changes and exit this menu.
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OK Button: Click on the OK Button to save your changes and try to execute the program. Note that you will need to specify the required data in order to complete the analysis and generate outputs. If there are any missing data, then the software will remind you to specify the data and click on Compute Outputs to generate analysis results.

Data

If you click on the Data button, you will see the following dialog box. Here you can specify the data required for this analysis. Data
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Search Data: The available data displays all the columns of data that are available for analysis. You can use the search bar to filter this list and to speed up finding the right data to use for analysis. Enter a few characters in the search field and the software will filter and display the filtered data in the Available Data box.
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Available Data: The available data box contains the list of data available for analysis. If your workbook does not have any data in tabular format, this box will display "No Data Found". The information displayed in this box includes the row number, whether the data is Numeric (N) or Text (T), and the name of the column variable. Note that the software displays data from all the tables in the current workbook. Even though data within the same table have unique column names, columns across different tables can have similar names. Hence, it is important that you not only specify the column name but also the table name.
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Add or View Data: Click on this button either to add more data into your workbook for analysis or to view more details about the data listed in the available data box. When you click on this button, it opens up the Data Editor dialog box where you can import more data into your workbook, or you can switch from the list view to a table view to see the individual data values for each column.
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Required Data: The code for the required data specifies what data can be specified for that box. An example code is N: 2-4. If the code starts with an N, then you will need to select only numeric columns. If the code starts with a T, then you can select both numeric and text columns. The numbers to the right of the colon specify the min-max values. For example, if the min-max values are 2-4, then you need to select a minimum of 2 columns of data and a maximum of 4 columns of data in this box. If the minimum value is 0, then no data is required to be specified for this box.
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Select Button: Click on this button to select the data for analysis. Any data you select for the analysis is moved to the right. To select a column, click on the columns in the Available Databox to highlight them and then click on the Select Button. A second method to select the data is to double click on the columns in the list of Available Data. Finally, you can also drag and drop the columns you are interested in by holding down the select columns using your left mouse key and dragging and dropping them in one of the boxes on the right.
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Selected Data: If the right amount of data columns has been specified, the list box header will be displayed in the black color. If sufficient data has not been specified, then the list box header will be displayed in the red color. Note that you can double-click on any of the columns in this box to remove them from the box.
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View Selection: Click on this button to view the data you have specified for this analysis. The data can be viewed either in the tablular format or you can view a graphical summary of the data selected.

Program

If you click on the Program button, the software will display the program code - an example screenshot is shown in the figure below. Pre-Process Inputs 3
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R Program: You can view the R program that will be executed here. This program is usually automatically generated from the options you have specified in the setup earlier. This is the program that will be executed by the R program to generate analysis outputs. If you like, you can edit this program.
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Auto Mode: If the radio button is selected as Auto, then the software will automatically update this code based on any changes you make in the input dialog box. We recommend that you use this option to generate the R program so that all your input settings are used to generate analysis results.
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Manual Mode: If you use the Manual option, then you will be allowed to edit the R program before the program is executed. Make sure that you specify a syntactically correct program; otherwise, the R program may report errors.

Verify

If you click on the Verify button, the software will perform some checks on the data you have entered. A sample screenshot of the data is shown in this figure. Pre-Process Inputs 4
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Verify Checks: The objective of this analysis as well as any checks that are performed are listed in this dialog box. For example, the software may check if you have correctly specified the input options and if you have specified the data correctly for analysis.
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Check Status: The results of the analysis checks are listed here. If the checks are passed, then they are shown as a green-colored checkmark. If the verification checks fail, then they are shown as a red-colored cross. If the verification checks result in a warning, they are shown in the orange color exclamation mark and finally, any checks that are required to be performed by the user are shown as blue info icons.

Outputs

Click on Compute Outputs to generate the outputs from this analysis. A sample screenshot of the worksheet is shown below. Example Heat Map
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Notes Section: The notes section contains a summary of the inputs used for creating the heat map. There are no specific analyses that are displayed in this section.
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Graph Section: The graph section shows the heat map that was generated. Review the heat map to see if it is able to convey the message you want for interpreting the data. Feel free to make changes to your inputs and redo the analysis until you are satisfied with the outputs.

Notes

Here are a few notes regarding this analysis:
  • If you want to review the R program that was used to generate this output, go to the %TMP%/Sigma Magic/ folder and look for the file smRScript.R after you execute the program. Note that this folder also contains other files such as error or warning output, text, and graphical output from running R. However, these files are stored in a temporary location and are not persistent between sessions.

Examples

Following examples can be found in the Examples folder within the software.
  • Create a Heat Map for the data shown in the file Heat Map 1.xlsm.

References

For more information on this topic, please refer to the following articles. Do note that if any external links are mentioned below, they are for reference purposes only.