Differences

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--- summer_2018:vpython_tips [2018/06/20 17:15]
tallpaul
+++ summer_2018:vpython_tips [2021/06/24 16:02]
pwirving
@@ Line 49: / Line 49: @@
 print(A) #This will then print out the number 21
 </code>
-  * **Dot Product** - the dot product is a way to [[184_notes:math_review#Vector Multiplication|multiply two vectors]]. Python has this command already programmed in:
+  * **Dot Product** - the dot product is a way to [[http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:math_review#Vector Multiplication|multiply two vectors]]. Python has this command already programmed in:
 <code>
 A=vec(1,2,3)
@@ Line 62: / Line 62: @@
 CD=cross(C,D)  #This will calculate (6*1-2*7)i-hat - (5*1-7*2)j-hat + (5*2-6*3)k-hat
 print(CD)  #This will print out the vector (-8, 9, -8)
+</code>
+/*
+There are a few ways to graph in python, but a common method is via gcurve. If the values you wish to plot are changing over time in a loop, be sure to put the plot command in the loop with them, and plot each point for each iteration of the loop.*/
+<code>
+ExampleGraph = gcurve(color=color.green, label = 'Data Points')  #First, define the graph.
+ExampleGraph.plot([1,2],[3,4],[5,6])  #This will plot the three points listed, connected by a line.
+</code>
+*/
+  * **Graphing** - One method of graphing involves using physutil, which is a library that needs to be imported. From there, the syntax is similar to gcurve. MUST use GlowScript 2.9 or lower; anything higher will not import properly.
+<code>
+get_library('https://cdn.rawgit.com/PERLMSU/physutil/master/js/physutil.js')  #Imports physutil
+MassOfBall = 20
+SpeedOfBall = 10
+t=0
+dt=0.1
+tf=10
+ExampleGraph2 = PhysGraph(numPlots = 1)   #Defines graph window
+while t < tf:
+    rate(50)
+    KineticEnergy = 0.5*MassOfBall*SpeedOfBall**2
+    ExampleGraph2.plot(t, KineticEnergy)   #Plot function is identical
+    SpeedOfBall = SpeedOfBall - 0.5
+    t = t+ dt
+</code>
+  * **MotionMaps** - MotionMaps track an object and plant arrows in a trail behind the object. The size and direction of the arrows is controllable, so it can be a useful method to demonstrate any vector quantity of an object, such as velocity or Force. MUST use GlowScript 2.9 or lower; anything higher will not import properly.
+<code>
+get_library('https://cdn.rawgit.com/PERLMSU/physutil/master/js/physutil.js')  #Imports physutil
+Moving_Sphere = sphere(pos=vector(0,0,0), radius = 0.5, color = color.cyan)  #The object we want to place arrows for, a cyan sphere.
+Sphere_velocity = vector(5,5,0)  #Let's say we want a MotionMap for the velocity of this sphere.
+Setting up time parameters for the motion
+t=0
+dt=0.1
+tf=10
+#Creating the MotionMap via MotionMap(object, stop time, number of arrows, arrow size, arrow color, number labels on arrows or not)
+Moving_Sphere_MotionMap = MotionMap(Moving_Sphere, tf, 5, markerScale=1, markerColor=color.orange, labelMarkerOrder=False)
+while t < tf:
+    rate(100)
+    Moving_Sphere.pos = Moving_Sphere.pos + Sphere_velocity * dt   #Sphere is moving according to its velocity
+    Moving_Sphere_MotionMap.update(t,Sphere_velocity)   #MotionMap update function plots the vector as time goes by
+    t = t + dt
 </code>