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There are a bajillion different charts available  in software like excel or numbers or sheets or  
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mathematica or plotly, but I recently discovered  that pretty much all plotting apps - as far as I  
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can tell - are missing an incredibly basic type of  chart! Consider this video my attempt to convince  
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you it's a scandal these charts are missing,  and my attempt to convince software developers  
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to add them into their plotting software. Ok, so suppose you want to compare the climates  
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of London, England; London, Ontario; and London,  Kentucky. Here's a table showing the average and  
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seasonal high and low temperatures for each  London. But tables are boring. If you wanted  
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to plot this data by hand, you might imagine  using a chart like this to show the range of  
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temperatures and allow you to see at a glance that  the climate in London England is less extreme than  
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the other Londons, (which are each similarly  variable but with Ontario shifted colder) - a  
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bar chart makes more sense than, say,  a point chart since the temperatures in  
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these Londons can by definition be in between  the minimum and maximum ones in our table. 
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The problem is, you can't easily  make a chart like this on a computer. 
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You can get close with an area chart,  which plots the temperatures correctly,  
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adds nice shading in between them, but also fills  the area all the way down (or up) to the X axis,  
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which isn't right. You can get around the  filling problem by creating a new table of  
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the differences between the temperatures  and plotting that as a stacked area  
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chart... oops - we need to remove the fill from  the lowest value - but it still doesn't make  
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sense to use a chart that draws connecting  lines in a situation like this where we're  
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talking about discrete geographic locations. You can also get close with a stacked bar chart  
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(or "stacked column chart" depending on whether  you think bars can be both horizontal and vertical  
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or if you think vertical bars have to be called  columns...) anyway, a stacked bar-column chart  
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separates out the cities correctly but incorrectly  adds the temperatures together - hence,  
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"stacked" - the columns are stacked together,  appropriate to the name, but it's not what we  
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want. You can get around the stacking problem by  again creating a table of the differences between  
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the temperatures, but then it still fills down  to zero even if you want the bars to start at  
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some other number, and the negative values are  a total nightmare" since stacked column charts  
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by default plot things from zero and if you enter  a negative number for the first value to try to  
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get it to start below zero, it plots that amount  below zero, but then measures the positive numbers  
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up from zero anyway and not from the negative  number - this is because stacked column charts are  
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meant for things like keeping inflows and outflows  separate, like, you bought 5 cats and sold 2, and  
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you want the total length of bars to represent the  total number of transactions (7) and not the final  
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number of cats (3). The only reasonable way I've  found to deal with negative numbers in stacked  
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column charts is just to add a big number to ALL  the temperatures so they're not negative anymore,  
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make the chart, then photoshop the y axis labels  to remove the big number. Which is ridiculous. 
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What we're actually looking for is something  called a "range chart" where you enter the  
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top and bottom values of the range and then  the program draws that for you. Specifically,  
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we want a "stacked range bar chart" where you  can enter multiple numbers, including negative  
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numbers, and then draw bars between them. Is  that too much to ask? I guess, I guess it is. 
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ps here are a few more examples of data that  really would benefit from being visualized  
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with a stacked range bar chart but first, a big  thank you to my Patreon supporters who help make  
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these videos possible - please consider supporting  MinutePhysics at patreon.com/minutephysics. Now,  
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back to the benefits of stacked range bar charts!  Really, any chart where the x axis is a discrete  
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set of things and the y axis is a range that can  go below and above zero is a candidate for this  
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type of chart. Like, if you wanted to plot the  range of latitudes of each of the continents,  
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or show when twilight, dusk, and daytime are  at a given location. Or compare percentiles  
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for student grades in different classes. Or  the local climate: plotting the average daily  
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low and average daily high temperatures for  each month along with the average monthly low  
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and high temperatures and the record monthly low  and high temperatures across a year gives you a  
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picture of the seasonal variation in temperature  for a particular location. Yes, you can do this  
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with a stacked area chart, but that makes less  sense than stacked columns because area implies  
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some sort of continuity when to create the data  you are literally binning or averaging by month.