Merge pull request #840 from androidx/add_plotTool

adding plot tool

Author: jafu888

desktop/PlotTool/.idea/.gitignore

@@ -0,0 +1,27 @@
+import androidx.constraintlayout.desktop.graph.GraphEngine
+import androidx.constraintlayout.desktop.graph.Utils
+import java.awt.Color
+import kotlin.math.cos
+import kotlin.math.sin
+
+fun main(args: Array<String>) {
+    val frame = Utils.smartFrame("Simple k Plot")
+    val p = GraphEngine.setupFrameWidthControls(frame, "wave")
+    val min = -Math.PI
+    val max = Math.PI
+    p.addFunction("sin", min, max, Color.BLUE) { x -> sin(x) }
+    p.addVelocity("dsin", min, max, Color.GREEN) { x -> sin(2 * x) }
+    p.addFunction2("cos", min, max, Color.RED) { a -> cos(a) }
+    p.addFunction2d("circle", min, max, Color.PINK,
+        { t -> Math.cos(t) },
+        { t -> Math.sin(t*2) })
+    val x = DoubleArray(20)
+    val y = DoubleArray(x.size)
+    for (i in y.indices) {
+        val t = min + i * (max - min) / y.size
+        x[i] = Math.sin(t)
+        y[i] = 2 * Math.cos(t)
+    }
+    p.addPoints("points", Color.WHITE, x, y)
+    frame.isVisible = true
+}