Knowledge Base: How do I display my data in FCS Express as it appears in the summit software?

The latest versions of Summit Software save data in 32 bits which can cause the display of your plots to look incorrect in FCS Express. The instructions below should only be followed if you are noticing a problem with the way the data is displayed.

How do I display my data in FCS Express as it appears in the Summit Software?

FCS data in the Summit software is displayed on a 0-256 linear or 0-100,000 logarithmic scale. However, the data is stored in the data file as 32 bit data with a range of 0-4,294,967,295. When the data is viewed in FCS Express the 32 bit native values are displayed on the axis and used for subsequent calculations such as means and medians.

There are two options for rescaling or displaying the data in FCS Express

  1. Use the Divide by Axis Labels feature: Using the Divide by Axis Label feature will display the axis as they are seen in Summit but will not change the native raw data or statistical values.
  2. Use the Parameter Math Feature: Using Parameter Math will create a new parameter based on the scaling factor. The native raw data values will also be scaled accordingly.

Using the Divide by Axis Labels Feature

The Divide by Axis Labels feature may be accessed by right clicking on a plot>choose Format>Axis Category>Divide By Factor. Using the Divide by Axis Labels feature will display the axis as they are seen in Summit but will not change the native raw data or statistical values.

For Linear Parameters type the value 16777216 into the Factor box.

 

For Logarithmic (fluorescence) Parameters type the value 42949.67296 in the Factor box.

 

Once values have been entered click OK. Below is an example of the data before and after making the Divide by Axis Labels change.

Summit data before applying the Divide By Axis labels change. Summit Data after applying the Divide By Axis labels change. Notice the Axis values have been updated according to the scaling factor but the X and Y Median values have not changed.

Using the Parameter Math Feature

The Parameter Math feature may be accessed in the Transformation Navigator from the Tools tab>Transformations>Transformations command. More detailed information about setting up parameter math can be found in our Using Parameter Math Manual Topic. Using the Parameter Math feature will create new parameters based on the scaling factor resulting in parameters that are displayed on the correct scale and raw data values that reflect the scaling change.

In Transformations navigator, create new parameter math and click New below Formula Sequence box to add sequence for linear parameter. The Create New Sequence Item dialog will appear. Enter formula as depicted in image below and click OK.

For Linear Parameters use the scaling factor of 16777216 to divide the parameter number by. In the example below SSC-A is represented by P8 so the resulting formula is: =P8/16777216.

In Transformations navigator,click New below Formula Sequence box to add new sequence for logarithmic parameter. The Create New Sequence Item dialog will appear. Enter formula as depicted in image below and click OK.

For Logarithmic (fluorescence) Parameters use the scaling factor of 42949.67296 to divide the parameter number by. In the example below FL-1 is represented by P10 so the resulting formula is: =P10/42949.67296

Once parameter math formula sequences have been defined, click and drag the newly created parameter math from the Transformation navigator to the plot. Below is an example of the data before and after performing parameter math on the data. Please note that you may also overwrite the original parameter by choosing it from the Output Parameter drop down in the Create New Sequence Item dialog. Once applied, the new parameters will be available from the x- and y- axis drop down lists on the plot, and "Parameter Math applied" will be appended to the plot title.

Summit data before applying performing parameter math on the data. Summit Data after performing parameter math. Notice the Axis values have been updated according to the scaling factor and the X and Y Median values have changed to reflect the newly created parameters.