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Hello Chad,
Thank you for posting this question, especially as I imagine quite a number of those who wish to use CODAP with real data find themselves in similar situations.
One very incidental help is an improvement to your formula for HOURS. I suggest “HOURS=split(Start_Time, “:”, 1)” which will grab the first item in a list delimited by the colon.
As you may know, you can create a CODAP “plugin” that massages the data. You can learn about these in this Getting Started Guide. But, of course, you have to know a bit of JavaScript to create a plugin.
Another approach might be to automate the preparation of the data using something like Excel Macros. If you aren’t able to do this yourself, perhaps you can find a spreadsheet guru who could whip something up. I think the end result would allow students to quickly transform their csv into something ready to drop in and use in CODAP.
Bill
Hi Kimberly,
Regarding how to make a dataset with different numbers of colored balls: You don’t actually have to write a formula. You can do it using CODAP’s case table as shown in this video.
Hello Sandra,
I wonder if you have looked through the CODAP help. This is a good way to get started.
Bill
Suppose we have numeric values ranging from 1 to 100 that we wish to break into three groups: “low,” “medium,” and “high.”
We use the formula:
if(Number<33,”low”,
if(Number<66,”medium”,”high”))The screenshot shows the formula for this as it appears in the formula editor.
Hope that helps.
Bill
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¡Hola Hugo!
It’s wonderful to hear that you’re using CODAP in this way. Truth be told, we don’t yet have an easy way for users to share documents with the user community. But perhaps now is the time. Would you mind sending a link to a shared view of your pyramids data so we can take a look?
And BTW, are you and your on-line users using the Spanish version of CODAP? If so, do you have any recommendations for improving the localization?
Bill
Hi Traci,
My favorite way to do this is to drag the original attribute all the way to the left so that things are grouped by those categories. Then edit the “none” cell to say “none to little” and, likewise, edit the “little” cell to say the same thing.
They won’t instantly combine (too bad), but if you drag the attribute back to the right and then back to the left, you’ll see that they have been combined.
Hope that helps,
Bill
Ah, that makes it clear. I’m guessing you don’t really need points plotted in each state? If that’s true, then rename latitude and/or longitude to something CODAP won’t recognize as lat/long. I often add an underscore to the end of the name. Then when you drop an attribute on the map you’ll just get a legend for the boundaries.
Hope that helps!
Hi Andee,
Though I don’t see an attachment, I’m guessing that your map has two “layers” from the same dataset; e.g. States’ boundaries and cities as points with latitude and longitude. Let’s assume the States are at one level and the cities at the level beneath. Now, you drag a categorical attribute for cities into the map and you get two legends. Ugh!
This is a bug that I fixed yesterday. It will appear in build 0476.
In the meantime you can click on one of the legend attribute names and use the resulting menu to remove that legend. The other legend will remain.
Now if, by chance, both layers are at the same level, then the problem will persist even after the bug fix and there’s some question about what the behavior should be. Similarly, if the legend attribute belongs to the higher level, the problem will also persist, again with more design thinking required.
Thanks so much for posting your question, and I hope this response helps, at least a bit.
Bill
Hi Joachim,
It sounds like you’ve already figured out the (few) ways there are to do statistical simulation in CODAP, which remains far behind the capabilities built into Fathom.
Bill
Hi Wendy,
CODAP doesn’t have any curve fitting capabilities (beyond linear). Of course it’s possible to fit a curve from a chosen family by setting up a slider to vary, and computing squares of residuals whose sum can be minimized, but this is a lot of work.
Bill
Hi Andee,
Regarding the formula workaround, I just thought of a simplification:
(caseIndex+10)+”_”+State
The goal is that the computed value sort alphabetically to the same order as the states appear in the table.
caseIndex is the row number in the table. By adding 10, we avoid the complication that alphameric sorting places “10_” before “2_”. So once the states are sorted in decreasing order of Lyme disease incidence, the values computed by the formula will also sort in that order and that will be the default order in which they appear on a categorical axis.
Confusing? You bet! 🙂
Regarding the connection between case order in the table and order of categories: We regard these two things as conceptually distinct. Suppose, for example that you have census records of people, each with a marital status. We don’t say that the order of the records should determine the order in which ‘married,’ ‘divorced,’ ‘never married,’ etc should appear on a categorical axis. The default order is alphabetical, and the user can change that order manually.
But perhaps this brings up a research question: How do learners regard categorical values, and how do they come to understand the different ways they can be used in data visualization and analysis?
Hi Andee,
So you didn’t want to drag the states to the desired order?
I was stuck for quite a while and almost gave up the search for an automated solution. But, as you can see in the screen captures, I was able to create a new attribute whose alphabetic order is in order of decreasing incidence.
So that gives you a “workaround” but it’s hardly a generally useful solution.
One wrinkle is that most of the time a given category (State in this case) has more than one value. So you would have to plot something like a mean to have single-values to order by. Then you could have a command somewhere in the graph interface to Order by Value.
But do we want to add something to the interface to automate a task seldom encountered and that can be done manually?
Bill
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Hi Joachim,
CODAP determines how to group connected lines by the grouping at the leftmost level of the case table. So you can produce the effect you want by dragging the country attribute to the left in you case table so that it forms a new level.
If the legend attribute is the same as the grouping attribute, then the points and lines will get the same colors.
Bill
Hi Colin,
Many web sited, including google and youtube do not allow themselves to be embedded in an iFrame. Try https://en.wikipedia.org/wiki/Cats_(musical)or concord.org to see that some URLs work.Bill
