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Giving Thanks for Ways to Edit a Bar Chart of Pies

My siblings occasionally remind me that because I’m getting older, one day, my metabolism is going to collapse. When that day comes, consuming mass quantities of food will surely lead to the collapse of my body, mind, and soul. But, as that day is coming slowly, on Thanksgiving, I’m an every-pie-kind-of-guy.

Now, I know what you’re thinking. It’s Thanksgiving. I’ve just mentioned pies. We’re going to look at pie charts of pies. If you really want to look at pie charts of pies, go ahead and get it out of your system:

2008 survey by Schwan’s Consumer Brands North  America

A Robot that Puts Pie Charts onto Actual Pies

In this post, we’re going to do something more like this:

At our house, we usually do three pies for Thanksgiving: Pumpkin, Chess, and Pecan. I’m going to use a chart of these to show you the things I’m most thankful you can do after you’ve made your bar chart in Minitab. Let’s say that we start with a chart of the calories per slice.

The default graph has all blue bars. In this case, the order of the bars is the order from the worksheet.

Reorder the bars

These bars are presently in the order that they were listed in the worksheet. But I like to eat them in order of difficulty, starting with the pecan and easing towards the pumpkin. This tends to follow the order of the calories, so we can put the pies in descending order.

  1. Double-click the bars.
  2. Select the Chart Options tab.
  3. In Order Main X Groups By, select Decreasing Y. Click OK.

The pecan pie is on the left because it has the most calories. Other pies follow in descending order.

Add labels that show the y-values

Bar charts are great for making comparisons. Ordering them makes it even clearer which categories are greatest and which are least. But if you want to get precise numbers, you can easily add labels that show the values from the data.

  1. Right-click the graph.
  2. Select Add > Data Labels. Click OK.

The numbers above the bars give the exact number of calories per slice.

Accumulate bars

As an every-pie-kind-of-guy, one of the things I might want to know is how many calories I eat when I have a slice of each pie.  That’s the kind of situation when it’s helpful to accumulate Y across X.

  1. Double-click the bars.
  2. Select the Chart Options tab.
  3. In Percent and Accumulate, check Accumulate Y across X. Click OK.

The resulting graph shows the number of calories for a slice of pecan, for a slice of pecan and a slice of chess, and for a slice of all 3.

The right bar shows the number of calories if I eat one slice of each pie.

Edit the fill patterns

Like when you’re making a graph about pies, it’s often helpful to make colorful bars that help to represent the categories in the data. In this case, all you have to do is follow these steps:

  1. Click the bars in the graph once to select all of them.
  2. Click one of the bars in the graph once to select only one bar.
  3. Double-click the selected bar to edit the bar.
  4. In Fill Pattern, select Custom.
  5. From Background color, select the color that represents your category. Click OK.

For example, we could make the pecan bar “chestnut,” the chess bar “gold,” and the pumpkin bar “orange.”

Colors of the bars are the colors of the pies.

It’s generally best to leave this step to last, because some other editing steps, like changing the order, can change the bar colors.

Wrap up

Very often, editing a graph so that it presents the message that you want is easier once you’re able to see the graph. That makes it wonderful that it’s so easy to edit a graph after you’ve already made it in Minitab. To see even more about what you can do with different types of graphs, check out the list of graph options. And have a Happy Thanksgiving where you are!

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