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Hi, I have a Matlab data handling exercise that i really need done urgently (in 2 hours or under), it should not take more than 1 hour. The assignment involves calculating calibration data and making linear regressions. Please send me back the entire code used to calculate everything and the plots, I will pay whatever is necessary! Attached are the instructions and the submission sheet.

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E80 Matlab Assignment 3

Importing Data & Data Types

For this assignment, you will learn about a little bit about the most common types of Matlab

variables, then get more practice with regression and plotting. Finally, you will save your data as

two types of files (.mat and .txt).

Figure 1: Deploying the Iver2 AUV in Arctic seas.

Introduction

During the winter of 2006, Dr. Clark and 18 biologists flew to the remote field station named NyAlesund in the Arctic. The expedition took place in early January, during the polar night when the

researchers were subject to 24 hours of darkness. The goal of the expedition was to assess the

impact of the polar night on the underwater ecosystem using robots for sampling a large number

of variables.

The team brought 5 different underwater robots, one of which was Clark’s Iver2 AUV. Concerned

about the effect of the cold temperatures on battery duration, an experiment was set up at the

field station in which Arctic sea water was continuously pumped into and out of a water tank.

The Iver2 AUV was held submerged in the tank, with the prop motor running continuously at

100% for over 10 hours. The battery capacity (%) was logged throughout the experiment and

the data will be used for this Matlab assignment 3.

File Download

1. To complete the remainder of the assignment, you will need one file named

coldTankFullmission1.log that can be found here. Please download the file and put them

somewhere accessible to Matlab, (e.g. in the MATLAB directory often found under the

Documents directory in the file structure).

Data Investigation

1. Load the data from the file named coldTankFullmission1.log using the load function. For

example:

fileData = load(‘coldtankFullmission1.log’,’-ascii’);

2. Create a vector named batteryCapacity by extracting the first column of matrix fileData:

batteryCapacity = fileData(:,1);

Make sure you understand the difference between extracting a row versus a column

from a matrix.

3. Use the size() function to determine the dimensions of the batteryCapacity vector.

4. Create a timeSequenceInSeconds vector that starts at 0 and increments in 0.5 second

intervals. The vector should have the same dimensions as batteryCapacity.

5. Create a timeSequenceInHours vector by converting timeSequenceInSeconds to hours.

6. Plot the batteryCapacity vector as a function of timeSequenceInHours.

7. Add a label to the x and y axis (i.e. using the xlabel and ylabel functions). Be sure to

include units.

8. Observe your plot. Is the battery capacity decrease over time a linear, quadratic, or

exponential function?

9. Save the plot as a jpg, and add it to your submission sheet for this assignment.

Calibration

10. Use the polyfit to construct a linear model of the battery capacity as a function of time.

Store the slope and intercept values in a vector named P.

P = polyfit(timeSequenceInHours,batteryCapacity,1);

11. Add the value 10 to the intercept of the linear model so that the line crosses the y-axis at

approximately 100 %.

12. On a new Figure, plot the linear model from step 10. and step 11. Add a label to the x and

y axis (i.e. using the xlabel and ylabel functions). Be sure to include units. Also add a title

to the plot, e.g. ‘Iver2 Battery Capacity for Near Freezing Water Conditions’.

13. Save the plot as a jpg, and add it to your submission sheet for this assignment.

Calibration Errors

14. Use Matlab to calculate the confidence intervals 0 and 1 associated with the slope

and intercepts of the linear model calibration. Assume that the confidence intervals

bound the actual values with 99.9% confidence, (i.e. use the 0.001 column on the t

table). Lecture 2 contains equations that may be useful. Add these confidence limits to

the assignment 3 submission sheet.

Error Propagation

15. Use Matlab to calculate the battery capacity, when it is initially measured to be 53%, and

it is run for exactly four hours. That is, use the slope of the calibration to determine the

change in battery capacity over four hours, and add this change to 53%.

Using the propagation of errors equations (with quadrature), calculate the error

associated with the battery capacity calculation in the step 15. Write this error on the

submission sheet.

You can assume the error in the slope of the line is equal to the confidence interval 1.

Also, assume the error in the initial battery capacity (53%) is 1%.

Saving The Data – Part 1

16. Use the save function to save the variables batteryCapacity, timeSequenceInHours, and P

in a .mat file named batteryData.mat.

17. Clear all variables from Matlab’s workspace using the clear function.

18. Type who and confirm there are no variables left in the workspace.

Strings and Numbers

19. There are many data types in Matlab, but you don’t have to declare a data type (unlike

most programming languages) when you create a new variable. For example, the

following command will create a variable named newFloat with a value of 7.65.

newFloat = 7.65;

20. In the above example, the variable newFloat is of floating point type. Type the following

commands, one at a time, to confirm this:

isinteger(newFloat)

isfloat(newFloat)

isstr(newFloat)

21. Repeat this exercise with a variable named newString.

newString = ‘Hello’;

isinteger(newString)

isfloat(newString)

isstr(newString)

22. It is also possible to convert between data types. E.g.

anotherNewString = ’42.5’

anotherNewFloat = str2num(anotherNewString)

Note: An introduction to these data types can be found here.

Saving The Data – Part 2

23. Use the load function to load batteryData.mat.

24. Create a string named fileName, and set it equal to outputFile.txt

25. Use the fopen function to open fileName for writing to. You may need to research how

fopen works.

fid = fopen(fileName, ‘w’)

26. Use the fprintf function to write two columns of data (i.e. timeSequenceInHours and

batteryCapacity) to fileName. For example:

fprintf(fid, ‘%d %dn’, [timeSequenceInHours’; batteryCapacity’])

Read up on fprintf if you don’t know how to use it.

27. Use the function fclose to close the file for writing. You can double check all the data is

there by opening up the file in a notepad or at the Matlab prompt typing:

type outputFile.txt

28. Submit the file batteryData.txt with your submission sheet on Sakai.

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