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dtan
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Re: Scatterplot trend line does not go through data
Thanks -- unfortunately with this fix (as in my Python demo) is that the y-axis is now in log-units. The ideal scenario we're trying for is to have the y-axis in their original units (e.g., 1, 10, 100), but with their spacing on a log scale, and the trend line reflecting the linearized relationship *after* the log transform. I can't find a clear way to plot the log-transformed datapoints with the values on the y-axis in the original scale, but with the trend line showing the now linearized relationship in PowerBI. In scripting-based plotting tools you can generally apply values to the y-axis for display purposes (e.g., have 1, 10, and 100, equispaced along the y-axis), while plotting the log-transformed data with the appropriate trendline. Is this possible in PowerBI? Is there a hacky workaround that can be done to display the y-axis in the original units, while plotting the log transformed data with trend line? More generally, it seems less than ideal to have a trendline *not* go through data after the axis is changed to a log scale (independent of my particular problem -- this is a platform-level issue).Re: Scatterplot trend line does not go through data
Sure. Here is a table of log-linear data that I created with python: x y 1 1000 2 784.76 3 615.8482 4 483.293 5 379.269 6 297.6351 7 233.5721 8 183.2981 9 143.845 10 112.8838 11 88.58668 12 69.51928 13 54.55595 14 42.81332 15 33.59818 16 26.36651 17 20.69138 18 16.23777 19 12.74275 20 10 When I plot this in PowerBI with y on a linear scale, the trend line is correct. When I plot with y on a log scale, the trend line no longer goes through the data. Linear scale: Log scale: The data were created so that the relationship is perfectly log-linear, and the line should go exactly through the datapoints. Here is a plot I made with the data in python with the y data plotted as log10(y):Scatterplot trend line does not go through data
I am adding a trend line to a scatterplot. As you can see in the attached screen shot, the line does not go through the data. I cannot figure out what is going on here. In fact, two of my colleagues have looked at this and we're all stumped. Things we've tried: Turning off all filters and slicers Filtering out blank values Filtering out values beyond the visible axes Turning off all axis limits (i.e., there is no data beyond the visible axes that could be pulling the line) The line does respond to changes in filters: if we turn filters/slicers on and off, the line will shift, but it never actually goes through the displayed data. Are there any other things that we should look at? Edit/Update: The y-axis is on a log scale. If I change the scale to linear, the line works properly. So, This appears to be a bug. When the y-axis is changed to log, the trend line continues to be on a linear scale. Is there any way to fix this? Screen shot of y-axis on a linear scale (same data) added for comparison. Log scale: Linear scale:
