How to read off a scatter with smooth lines graph on excel? - excel

Hi I have attached my graph and my data below:
My experiment is on Simple Harmonic Oscillators in an RLC circuit. I need to work out the quality factor. Where I need delta w which is the width of the resonance curve at imax/sqrt(2). With the Y axis being my current and Imax being 0.4229 so 0.4229/sqrt(2) = 0.299. So I need to read the frequencies (x values) at the points 0.299 on the y axis in order to work out the width. I was wondering how I can do this on excel. Obviously if this was on paper I could just draw straight lines but I'm on excel and unsure and hoping someone could help. Thanks

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I have a straight trendline on a semi-log chart (ie y axis in log scale, and x axis (ie time) in regular scale).
I think therefore the equation of that straight line is y = a * b^x
I want to move the line up or down though according to trigonometry but don't know if I can as the opposite side of the triangle is in log scale. I can do this fine on regular scale charts, but I dont know where to begin for semilog charts.
Anyone know how I do this or if there's an equation I can use to calculate how much i move the line up or down?

QGIS does not change y and x coordinates to decimal degrees

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How to convert x and y coordinates into a heat map in excel?

I currently have a data set of x and y coordinates (position of an animal in an arena) over a period of time. I just used the coordinates to plot a scatter plot of what that looks like. However, instead of having every single coordinate as a separate point, i was wondering if there was a way to create a heat map of the points? So, the higher the likelihood of the animal in a specific area/ similar coordinates, the warmer the color? Hoping for the final product to be a depiction of the arena with a gradient of colors based on the likelihood the animal explores those regions?
Well with that many points, I don't know if Excel is the right choice if wanting to color-coordinate. The site https://app.rawgraphs.io/ has some really cool graphing capabilities. I use this when needing sankey's or something unusual that Excel cannot easily handle.
Here I used 1500 x/y points between 0 and 20. Then I selected the graph type called "Contour Plot".
Would this work?
Or here's a Hexagonal Binning chart of the same data...

Excel Scatter Graph - X (Performance) & Y (Volatility)

looking for a bit of assistance
I want a scatter graph with the X axix showing performance of an investment fund comparative to the Y axis which will have a volatility value.
Thus far the scatter graph takes the data and separates the two values out, I want the scatter plot to have incorporated both figures.
I have included an image showing, if someone could point out where I am going wrong?
Thanks in advance
ScatterGraph
When inserting your chart, make sure you choose the second option:

How can I plot the points of a curve?

I'm not great with Math at all and so-so with Excel. I have a requirement to calculate a series of values to apply as an offset for a price schedule. I know what I basically want to achieve with the offsets and how I want them to change across span of values but I don't know how I can plot these values or something close to it in Excel. For an idea of the curve I'm roughly trying to create you can plot these values:
0
20
30
35
38
39
39.5
40
40.5
40.75
41
41.125
41.25
Or if you don't want to use excel you can take a look at this chart image:
Now it was easy to quickly create that by entering some values and tweaking them to get a shape I roughly want, but I need 1000 data points! In other words, instead of the 13 point I provided above I would need 1000. This would be crazy to try and do manually.
I can think of two possible options:
Create the range of values with fewer points, then somehow
extrapolate that data set into more points. Maybe extrapolate isn't
correct but essentially convert 10 points of data into 1000
Interactively draw a curve and then have it plotted to values within
a defined min/max range
I've tried googling for help but I'm just coming up with tons and tons of "how to plot your data" sites - I need to work from the OTHER direction ;)
Thanks for any help or tips.
Like you said, you could draw a curve and plot those points, then put them into some equation solver to get an equation that could describe the curve you're looking for.
But just from looking at your curve above, you might be able to use an equation of the following form.
y = A - (B / x)
To make a curve similar to yours above, you might try...
y = 40 - (5 / x))
You can use a site like https://functionplotter.com/ to plot the function and play with the values of A and B until you have curve that you are satisfied with.
Is this kind of thing you are looking for?
spline interpolation in exel
XlXtrFun.xll
basically you already got 13 y's and 13 implict x's (1 to 13). You provide bunch of "x" values of small increment, like 0.01, 0.02, 0.03, ...,12.999 13.000, to this tool. then this tool will calculate y value for each of the ones. You will plot these as "x y scatter plot"
A simple and very accurate way is to plot the curve as an x-y scatter plot, and then fit a polynomial via Insert Trendline.
In this case a 4th order polynomial provides close to a perfect fit (R2 of .9973)
Y = -0.0139x4 + 0.4819x3 - 6.0607x2 + 33.026x - 26.718
You can also solve this without charts using LINEST, see Walkenbach's guide here. But charts provide the easiest reference

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