Scientific Computing for Physical Systems Spring semester, 2018 - - PowerPoint PPT Presentation

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Scientific Computing for Physical Systems Spring semester, 2018 - - PowerPoint PPT Presentation

Oct 05, 2022 237 likes •474 views

Scientific Computing for Physical Systems Spring semester, 2018 Course Goals Learn a programming language (Python) Learn some numerical algorithms (e.g., for solving differential equations) Explore some interesting physics:

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Scientific Computing
 for Physical Systems

Spring semester, 2018

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Course Goals

  • Learn a programming language (Python)
  • Learn some numerical algorithms (e.g., for

solving differential equations)

  • Explore some interesting physics: nonlinear

dynamics, chaos, celestial mechanics, many- particle systems, phase transformations

  • Have fun
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SLIDE 3

Course Format

  • Lectures / textbook / homework / exams
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Course Format

  • Lectures / textbook / homework / exams
  • Labs / projects / mini-lectures / quizzes

– 6 “canned” projects (66%) – Independent final project (20%) – Quizzes, attendance, etc. (14%)

  • No required textbook (see reference list)
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SLIDE 5

Projects

  • Making shapes (VPython graphics)
  • Projectile motion (1D and 2D)
  • Pendulum (chaos!)
  • Orbits (planets and asteroids)
  • Molecular dynamics (500 particles at once)
  • Random processes (statistical data)
  • Independent project (with paper and talk)
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Remember: This is a lab course.

  • Plan on spending plenty of time in this room.
  • Coordinate work times with your lab partner.
  • You’re graded on what you accomplish—not on

how smart you are.

  • Procrastination isn’t an option.
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Upcoming events

  • Fill out questionnaire before you leave today
  • Continue work on Project 1 this Wednesday and

Friday

  • Project 1 due Wednesday, Jan. 17, at beginning
  • f class (but finish by Friday if you can!)
  • First quiz will be Wednesday, Jan. 17, during

class (find errors/bugs in a short program)

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SLIDE 8

8AM 9AM 10AM 11AM 12PM 1PM 2PM 3PM 4PM 5PM

3:30 PM -4:20 PM

PHYS 2300L Schroeder

2:30 PM -3:20 PM

PHYS 2300 Schroeder

12:30 PM -2:20 PM

GEO 4750 (Yonkee)

10:30 AM -11:20 AM

GEO 3880

9:30 AM -10:20 AM

GEO 4150

1:30 PM -4:30 PM

GEO 4400L

12:00 PM -1:15 PM

GEO 4400

9:00 AM -10:15 AM

GEO 4220

3:30 PM -4:20 PM

PHYS 2300L Schroeder

2:30 PM -3:20 PM

PHYS 2300 Schroeder

12:30 PM -1:30 PM

GEO 4750 (occasionaly)

10:30 AM -11:20 AM

GEO 3880

9:30 AM -10:20 AM

GEO 4150

1:30 PM -4:30 PM

GEO 4220L

12:00 PM -1:15 PM

GEO 4400

9:00 AM -10:15 AM

GEO 4220

2:30 PM -3:20 PM

PHYS 2300 Schroeder

10:30 AM -11:20 AM

GEO 3880

9:30 AM -10:20 AM

GEO 4150

Fri Thu Wed Tue Mon

TY 127 Schedule, Spring 2018

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January 10

  • My office: TY 322, up two flights and through Physics
  • Dept. door, then to your right
  • Course web page:

physics.weber.edu/schroeder/scicomp

  • Questions on course policies?
  • Rules for collaboration and getting outside help
  • Contact me privately if you have concerns about

current or future lab partners.

  • Questions about Project 1, GlowScript, VPython?
  • Project 1 due 1/17, but try to finish by Friday
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Project 1: Making Shapes

  • print function
  • box, sphere, cylinder
  • Vectors
  • Colors
  • Variables
  • Arithmetic
  • while loop
  • Animation
  • Graphs
  • Comments
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Project 1: Making Shapes

  • print function
  • box, sphere, cylinder
  • Vectors
  • Colors
  • Variables
  • Arithmetic
  • while loop
  • Animation
  • Graphs
  • Comments

Features of the Python language itself

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Project 1: Making Shapes

  • print function
  • box, sphere, cylinder
  • Vectors
  • Colors
  • Variables
  • Arithmetic
  • while loop
  • Animation
  • Graphs
  • Comments

Features of VPython

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Project 1: Making Shapes

  • print function
  • box, sphere, cylinder
  • Vectors
  • Colors
  • Variables
  • Arithmetic
  • while loop
  • Animation
  • Graphs
  • Comments

Features of VPython What about cos, sin, pi?

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Project 2: Projectile Motion

  • Your first simulation project!
  • Solving differential equations (Newton’s second law) using

the Euler and Euler-Richardson algorithms

  • Dealing with inaccuracies in calculations
  • Physics: Air resistance, terminal speed, range
  • if statements
  • GUI controls (“widgets”)
  • Defining your own functions
  • Boolean variables and constants
  • Projectile1 program due Monday, January 22, 4:30 pm.

Rest of project due Monday, January 29, 2:30 pm

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Project 2: Projectile Motion

  • Congratulations!
  • Solving differential equations (Newton’s second law) using

the Euler and Euler-Richardson algorithms

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Project 2: Projectile Motion

  • Congratulations!
  • Solving differential equations (Newton’s second law) using

the Euler and Euler-Richardson algorithms

  • Interpolation
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Project 2: Projectile Motion

  • Congratulations!
  • Solving differential equations (Newton’s second law) using

the Euler and Euler-Richardson algorithms

  • Interpolation
  • Truncation errors — 3 ways to estimate:

– Compare to an exact calculation (when you can do one!) – Make dt smaller and see how much the results change – Monitor a conserved quantity (in next project)

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Project 2: Projectile Motion

  • Congratulations!
  • Solving differential equations (Newton’s second law) using

the Euler and Euler-Richardson algorithms

  • Interpolation
  • Truncation errors
  • Relating vector magnitudes to components
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Project 2: Projectile Motion

  • Congratulations!
  • Solving differential equations (Newton’s second law) using

the Euler and Euler-Richardson algorithms

  • Interpolation
  • Truncation errors
  • Relating vector magnitudes to components
  • Physics results: Air resistance, terminal speed, range
  • if statements, boolean variables and constants
  • GUI controls (button, slider, wtext)
  • Defining your own functions
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Project 3: Pendulum

  • More practice with Euler and Euler-Richardson

algorithms

  • This time the force depends on position,

velocity, and time

  • Angular variables: theta, omega, alpha
  • Natural units (m = g = L = 1)
  • Chaos!
  • Pendulum1 program due next Monday,

February 5, 2:30 pm.

  • Finished project due Monday, February 12,

2:30 pm.

  • Work with lab partners, but write your own

separate code and turn it in separately.

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Debugging Tips

  • Everyone makes mistakes! Relax and don’t feel guilty.
  • Test your program as frequently as possible.
  • Don’t take error messages literally, but do check line number.
  • Errors in a bound function don’t generate messages! (Actually

they do, but only in JavaScript console; try control-shift-J.)

  • To diagnose logical errors, insert print() functions to display

values of variables.

An ounce of prevention…

  • Keep code clean and organized.
  • Use comments as notes to yourself.
  • Break up large tasks into smaller ones, each in its own function.
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Project 3: Pendulum

  • Pendulum1 modeled a freely swinging

pendulum, measured period vs. amplitude.

  • Now add “damping” and “driving” torques.
  • Chaos!
  • Pendulum2 will model two pendulums with

slightly different starting conditions.

  • Pendulum3 will let you vary the drive

amplitude and observe phase space plots.

  • Finished project due Monday, February 12,

2:30 pm.

  • Work with lab partners, but write your own

separate code and turn it in separately.