University:
Georgia Southern University
Course:
ENGR1121 | Computing in Mechanical Engineering
Academic year:

2024
Views:

101

Pages:

1
Author:

Jalen W.

ENGR1121 – Computing Applications in Mechanical Engineering Lab 1D Arrays III: Vector Arithmetic, Vector Indexing (using find) and Logic Expressions Lab due: end of lab Total points: 20 Labs are to be individual work. You may use MATLAB Marina, MATLAB’s help, and your notes. Lab work will be graded during lab time and working results must be shown to the lab instructor by the end of the scheduled lab time. All MATLAB programs and functions must be completed and submitted in accordance with the Computing Assignment Format and the MATLAB Coding Style. Submit an electronic copy of your lab work to the appropriate Dropbox Folder in GSU’s Folio by the end of lab. No hard copy needed unless specifically requested by the instructor. Grading Each problem will be graded according to: program design (identifying inputs/givens, process, and outputs; algorithm) and program style (program comments, variable names, proper formatted input and output including units) 25%, and program correctness 75%. Lab Work 1. (10 points) Write a MATLAB script to solve this problem. Do not hard code any of the answers for this problem. You cannot use iteration for any of the parts of this problem. Define a vector: vec = [ 4 5 2 8 4 7 2 64 2 57 2 45 7 43 2 5 7 3 3 6523 3 4 3 0 -65 -343]; a. Create a new vector, vecind2, that contains the indices of every element in vec that is equal to 2. b. Create a new vector, vecno2, that is the same as the vector vec except that all of the 2s have been deleted. c. Create a new vector, vecR, that is the reverse of vec. d. Create a new vector, vecswap, that swaps the first and second halves of vec, so vecswap will contain the second half of vec followed by the first half of vec. e. Create a new vector, vecless45, that contains all of the elements in the vec that are smaller than 45. The numbers should be in the same order as they were in vec. f. Create a new vector, vecb10, that contains true wherever vec is greater than 10 and false everywhere else g. Create a new vector, vec2, that contains every other element of vec starting with the second element. h. Create a new vector, vec3R, that contains every third element of vec starting from the last element and going toward the first element in vec. 2. (10 points) Write a MATLAB program that will compute an approximation of the infinite series: 1 𝑠𝑠𝑠𝑠 = ∑∞ 𝑛𝑛=0 (2𝑛𝑛+1)(2𝑛𝑛+2). An approximation of an infinite series uses N terms instead of infinity. Test your program for N = 50; i.e. compute the sum for n = 0, 1, 2, … 50. The infinite series converges to the true value of ln ( 2 ) . Add statements to your program to compute the % error of the N-term approximation to series value − true value × 100 true value Your program should display the number of terms in N, the value of the series approximation, and for the last part, the percent error. Do not use iteration for this problem. Instead use element by element operations on arrays and the MATLAB sum function. MATLAB’s built in natural log function is named log. the value the series converges to. % error = 1 Instructor: Dr. Priya Goeser