Glitch in Connecting Lines Tool?

[Michelle Wilkerson]

Hi, CODAP team!

We’ve been having a great time using CODAP for some science explorations and arguments this week in middle school classrooms. We ran into what I think is a glitch, however. If we construct a graph with both x and y axes filled with attributes and then turn on “Connecting Lines”, everything is fine. But, if we then put a third attribute on the right-hand side, the Connecting Lines do not appear for the new data. Unclicking and re-clicking the “Connecting Lines” option does not fix the problem, we have to reconstruct the graph by making sure both attributes are added to the graph before turning on the “Connecting Lines” feature.

[Jonathan Sandoe]

Hi Michelle,

Thanks for the post. Currently, CODAP doesn’t support Connecting Lines for attributes on the right-hand side of the graph. I think the fall-back would be to create a second graph with the same x axis, but the right-hand y-axis attribute on the left. Not ideal, but at least you could compare the shapes of the two y-attributes.

Out of curiosity, would you say that the need for connecting lines for right-axis attributes was a common one? Should it be higher on our to-do list?

Jonathan

[Michelle Wilkerson]

Thanks, Jonathan. We are able to get the connecting lines to show up if we select it after adding the attribute to the right side, so we’ve been doing that.

We’ve has a need for connecting lines pretty frequently, to examine how two attributes change together over time (for example, reservoir levels and snowpack data during the California drought, where there is a lag of cycles as snowmelt moves to the reservoirs). We’ve found the connecting lines to be critical for when you want to compare attributes with different sampling rates – weekly reservoir levels, but monthly snowpack measures. We sometimes do create two graphs, but are using chromebooks in the classroom so fitting both graphs on the screen and still seeing details of their shapes is difficult.

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