Sample spreadsheet that is ready to be fit to the cubic expression y = ax + bx 2+ cx 3 + d using Excel’s regression package. Once the spreadsheet is set up as shown below, select Tools, Data Analysis from the menu bar and scroll down to Regression, select it and click OK.įigure 1. Note that in addition to x 1, x 2 and x 3 there must be a column containing x 0, which contains only ones. e., y = ax + bx 2+ cx 3 + d, where a, b, c and d are constants that we need to find), then we would create columns containing the independent variable to the desired powers, as shown in Fig. For example, if we wanted to fit a set of data to a third order polynomial (i. One simple trick is to create columns each containing the variable of interest to the requisite power. Seriously, let's just start from scratch.It is possible to have Excel perform a non-linear least square regression. Base 8 would make much more sense, just change our numbering system to match.
And while we're at it, why not have a meter be 12 inches, and then break into 10's from there? The only reason we use base 10 is because we have two hands of 5 fingers each. Tell you what, sort out the issue with time to a level that everything else works and we can get started. The end result is a statement that I can visualize.Īnd time, based on radians and divisible by 60, where's the metric for that, and how does that work. Yes, I know converting feet to inches is not as intuitive as metric but fine, I get my spreadsheet to do that automatically. I can distinguish between 5'8" and 5'11", but 172cm vs 180, takes too much thought. I mean, getting on a rant here, someone is 6 feet tall, that makes sense, but say they are 1.83 meters or 183 cm (18.2dm?) and it means nothing. Also I really like a foot as a basic unit of measure, meter is too long and cm too shore, and no one uses dm (which is still too shore at 5 inches). I've argued this before, pretty much everyone disagrees, but I don't care. Now when I scale up I typically do units in metric and then use a conversion to write the formula in pounds and gallons, but I almost always use F temperatures in that lab, mainly because I use the same thermometers I give my field reps which are in F.Īlso, if I had to change one this in metric it would be temperature, I am not the fan of cramming all the interesting temperatures between 0-100, and real life weather between -10-40, the scale my make sense but it lacks practicality. Main reason is that in production operators are usually non-technical and are familiar with pounds, gallons, and F, and trying to change units will ultimately confuse them (see reference to Mars fiasco). Liters becomes gallons, kg pounds, and almost exclusively temperature is in F. However, when we formulate for a customer or production facility everything usually converts over to imperial. If it is for research or experimentation we typically do everything metric. Honestly depends if we are working on benchtop or scaleup chemistry.
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