Adding a trend line to SEDs

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How to get Excel to fit a "trend line" to your SEDs, for bands K to MIPS 24 -- John Gibbs, 12 Nov 11.

To add a trend line for a specific region of a chart, a second data series must be added to the chart. Assuming the SED has already been created, right click on one of the data points on the chart and choose Select Data. In the box under Legend Entries (Series), select Add. Click in the Series X values and drag through the data column containing the K-MIPS24 log(lambda) data. Once the X values have been selected, highlight the {1} in the Series Y values and then drag through the data column that contains the log(Flux*lambda) values. Click Ok and then click Ok again. The new data series is now overlaying the original data. Right click on one of the data points for the new series (make sure only the K-MIPS24 data points are highlighted) and select Format Data Series. Select Marker Options then None and close the box. To add the Trend line to the chart, left click one the one of the K-MIPS24 data points (again, make sure only the K-MIPS24 points are highlighted) and select Layout from the menu bar. Choose Trendline then More Trendline Options. Select the Linear and Display Equation on chart options and close the box. The trend line should now be displayed on the chart from K-MIPS24 with the equation below it. The equation may need to be repositioned on the chart. You can copy the slope into your notes from there.