2019 Spring - MAT 2680 - Reitz

"...how it differs from the rocks"

Category: Assignments (Page 1 of 3)

OpenLab #3: Advice for the future

May 9, 2019 / / 53 Comments

(Due Tuesday, 5/21/19, at the start of class).  Imagine that you are invited to speak on the first day of MAT 2680, to give advice to entering students.  Write at least three sentences responding to one or two of the following, describing what you would tell them.

  1. What do you wish that you had been told at the start of this class, to help you succeed?
  2. Choose one topic in the course that is especially challenging. Identify it, and give advice to students trying to master that topic.
  3. What is the most important prior knowledge (not taught in the class) that you need in order to succeed?  Why is it important?

Extra Credit.  Respond to someone else’s comment.  Do you agree? disagree? Have anything to add?

Assignments Week 14

May 7, 2019 / / 0 Comments

WeBWorK:  Assignments 14-InverseLaplaceTransforms, and 16-LaplaceIVP  are due Tuesday, 5/24, at midnight.
OpenLab:  OpenLab #3, Advice for the Future, is due on Tuesday, 5/21 (the day of the final exam).

OpenLab #2: Numerical methods PROJECT – Scoring Guide

April 28, 2019 / / 0 Comments

Hi everyone,

Your overall grade (out of 20 possible) for the numerical methods project has been posted under Dashboard/OpenLab Gradebook.  The scoring guide that I used to assess your work is given below.  If you’d like more details about your score, please send me an email or ask me after class.

Regards,
Prof. Reitz

 

NUMERICAL METHODS PROJECT

SCORING GUIDE

20 points total (Written Assignment + Implementation)

WRITTEN ASSIGNMENT – OpenLab (5 points total):

  • 1 point – 300 words minimum
  • 2 points – Describe project & how it works, Describe process of building it (what tech did you use/why? Unexpected challenges?)
  • 1 point – Why do we need numerical methods?  Why is this assignment included in the class?
  • 1 point – include link or state you will send by email

IMPLEMENTATION (15 points total):

3 points: General setup
  • 2 points – Correct differential equation: dy/dx = x^2/(y-1)
  • 1 point – Correct initial condition y(-1)= -0.5
4 points: Euler’s Method
  • 2 points – functioning solution, displays x,y,f(x,y) at each stage
  • 1 point – correct x-target value
  • 1 point – four digits of accuracy after decimal:  y(2)=-1.87228… (will accept -1.8722 or -1.8723), optimum # of steps 11795
4 points: Improved Euler’s Method
  • 2 points – functioning solution, displays x,y,k1,k2 at each stage
  • 1 point – correct x-target value
  • 1 point – four digits of accuracy after decimal:  y(2)=-1.87228… (will accept -1.8722 or -1.8723), optimum # of steps 291
4 points: Runge-Kutta Method
  • 2 points – functioning solution, displays x,y,k1,k2,k3,k4 at each stage
  • 1 point – correct x-target value
  • 1 point – four digits of accuracy after decimal:  y(2)=-1.87228… (will accept -1.8722 or -1.8723), optimum # of steps 12

Assignments Week 12 & WeBWorK NEW FEATURE ‘MathQuill’

April 14, 2019 / / 0 Comments

Assignments Week 12

WeBWorK: Assignments 12-Trench-EulerEquations  and 13-Trench-VariationOfParameters**  are due Tuesday, 4/30, at midnight.
** WeBWorK problem set 13 will be assigned no later than Tuesday, April 22, and will be due on 4/30.

OpenLab: None

 

 

New Feature in WeBWorK

WeBWorK now has “MathQuill” enabled by default, which allows more natural “pretty print” input for your answers.  You don’t have to do anything special to use it – once you click in an answer box, it will start working.  It will detect the mathematical symbols you type and display the answer correctly onscreen – (for example, when you type a fraction “/”, it automatically becomes a vertical fraction).  There is also a popup menu with common expressions such as radicals.

WHAT IF I WANT TO TURN THIS FEATURE OFF?  You can control this in WeBWorK under User Settings/Use live equation rendering.

Assignments Week 9

March 25, 2019 / / 0 Comments

WeBWorK: Assignment  9-Nonhomogeneous  due Tuesday, 4/2, at midnight.
NOTE: Because of our exam on 4/2,  assignment 10-Trench-ReductionOfOrder will be due the following Tuesday, 4/9.

OpenLab:  OpenLab #2: Numerical Methods PROJECT is due Thursday, 4/4, by the start of class.

 

OpenLab #2: Numerical Methods PROJECT – Part 2

March 19, 2019 / / 39 Comments

This post contains additional information related to the Numerical Methods Project earlier in the week, due April 4th.

Submission guidelines. Your completed project will consist of three elements:

  1. A working numerical methods calculator using your choice of technology (spreadsheet, programming, mathematical software), as described in the previous post.
    HOW TO SUBMIT:

    • If your project is a spreadsheet, either share it with me (if it is in Google Docs or a similar cloud-based platform), or email the file to me as an attachment.
    • If your project is code, please submit it using an online coding site like ideone.com – once your code is working on the site, you can simply submit a link.  If you are using a programming language not supported by ideone.com, you can email the source code to me.
    • If your project uses mathematical software, either share it with me (if it is in MatLab Online or a similar cloud-based platform), or email the file to me as an attachment.
  2. Solutions to the following example using each of the three methods studied in class (Euler’s Method, Improved Euler’s Method, and Runge-Kutta), generated by your numerical methods calculator.  Submit using the same method as in part 1.

Project Example.  Given the differential equation dy/dx = \frac{x^2}{y-1} and initial condition y(-1)=-0.5, approximate the value of y(2) using Euler’s Method, Improved Euler’s Method, and Runge-Kutta.

For each method, choose a step size that gives four correct digits following the decimal point.  How many steps are required to obtain this level of precision?

NOTE: The actual solution is y(2)=-1.87228…

  1. Writing assignment.  Write one or two paragraphs (minimum 300 words) responding to the following.  Leave your response as a comment on this post.
    1. Describe your project and how it works.
    2. Describe the process of building your numerical methods calculator.  What kind of technology did you decide to use, and why? Did you encounter any unexpected challenges in completing this project?
    3. Why do we need numerical methods in addition to the other methods studied in the class?
    4. Why is this assignment included in the class (instead of just computing the various methods using a calculator)?
    5. Please include a link to your project (if it is online), or clearly state that you will be sending me the files by email (and don’t forget to do it!).

 

Exam 1 SPECIAL OFFER Scoring Guide

March 16, 2019 / / 0 Comments

For your reference, here is the scoring guide I will be using for the EXAM 1 Special Offer

-Prof. Reitz

 

Name: ____________________

 

____ Includes Name, Date, Problem #s, original scores (up to 6 points deduction)

____ Presentation is neat, well-organized, readable (up to 4 points deduction)

____ Includes Original Exam

____ Max bonus (30 points for <50%, 20 points 50%-59%, 15 points 60%-69%, 10 points 70%-79%, 5 points 80%-89%)

 

First problem #:  ____

____ Original Score (out of 25)

____ Revised Score

____ (up to 5 points deduction if incomplete) Written explanation,  2 sentences,  what you did wrong OR how to solve the problem.

____ Bonus points earned for problem 1

 

Second problem #: ____

____ Original Score (out of 25)

____ Revised Score

____ (up to 5 points deduction if incomplete) Written explanation,  2 sentences,  what you did wrong OR how to solve the problem.

____ Bonus points earned for problem 2

 

EXAM 1 SPECIAL OFFER BONUS POINTS:   _______

(Bonus points for problems 1 and 2, with maximum bonus based on original exam score, minus any deductions, ).

EXAM 1 REVISED SCORE: ______
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