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@@ -140,13 +140,11 @@ To plot a curve that is described by parametric equations, we compute the $$x$$
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---
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-3. The file `main.cpp` (in Sources) contains the function `main()` where you will be adding code. Open this file and study the code.
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-
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- ```
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+3. The file `main.cpp` (in Sources) contains the function `main()` where you will be adding code. Open this file and study the code.
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- QApplication a(argc, argv);
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- XYPlotWindow wLine;
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- XYPlotWindow wCircle;
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+ QApplication a(argc, argv);
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+ XYPlotWindow wLine;
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+ XYPlotWindow wCircle;
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XYPlotWindow wHeart;
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XYPlotWindow wButterfly;
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@@ -166,7 +164,6 @@ To plot a curve that is described by parametric equations, we compute the $$x$$
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// After all the points have been added, plot and show the graph
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wLine.Plot();
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wLine.show();
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- ```
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The line `XYPlotWindow wLine;` creates the object `wLine`, that is the window that will show the plot of a graph, in this case the graph of a segment. Look at the `for` loop. In this cycle several values for $$t$$ are generated and a value for $$x$$ and $$y$$ is computed for each $$t$$. Each ordered pair $$(x,y)$$ is added to the graph of the segment by the method `AddPointToGraph(x,y)`. After the cycle, there is a call to the method `Plot()`, to "draw" the points on the graph, and to the method `show()`, to show the plot. The *methods* are functions that allow us to work with the data of an object. Note that each of the methods is written after `wLine`, and followed by a period. In a future laboratory experience you will learn more about objects and practice how to create them and invoke their methods.
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