Problem 44952. Find MPG of Lightest Cars

Created by Pooja Lalan

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Solve

Solution Stats

10380 Solutions
1371 Solvers

Last Solution submitted on Sep 29, 2020

Last 200 Solutions

Problem Comments

7 Comments

7 Comments

Show 4 older comments

Paul Hoffrichter on 2 Mar 2020

Never worked with Tables before. Does Cody offer any ways to debug?

Paul Hoffrichter on 2 Mar 2020

Answer: I am able to print intermediate results.

Arman Lalani on 19 Mar 2020

I am getting the answer but the order of elements in my vector doesn't match the required answer. How can I get it in the required order?

Hugo Ormo on 5 Apr 2020

I do not see why this does not work. It seems to work in the Workspace alright:
function mpg = sort_cars(N)
cars = load('cars.mat')
carsSorted = sortrows(cars,'Weight')
mpg = carsSorted.MPG(1:N)
end

Pooja Lalan on 7 Apr 2020

@Hugo, check syntax for load in the documentation https://www.mathworks.com/help/matlab/ref/load.html

Specifically, check what to expect when assigning output from load to a variable.

Hugo Ormo on 7 Apr 2020

ty @Pooja :)

Peter Chiappetta on 9 Apr 2020

I have been working at this for a bit and it seems like it should work, What am I missing?
function mpg = sort_cars(N)
load('cars.mat')
A = sortrows(cars,'Weight')
mpg=A(1:N,2)
end

Solution Comments

Solution 2625967

2 Comments

2 Comments

Umur Ulas Harman on 28 Jun 2020

it does not work if u did not put curly brackets. since otherwise u call a table. however, you need a column array to pass the test I believe.

function mpg = sort_cars(N)
load cars.mat
sorted = sortrows (cars,4)
n = N
mpg = sorted(1:n,2)
mpg=mpg{:,:}
end

priyanka p on 15 Jul 2020

Please share your full code if you have done it. It will be really helpful.

Thanks in advance

Solution 2581435

1 Comment

1 Comment

Piero Cimule on 19 Jun 2020

load cars.mat
sorted = sortrows (cars,4)
n = N
mpg = sorted(1:n,2)
mpg=mpg{:,:}

Solution 2263926

1 Comment

1 Comment

Tavish Pattanayak on 8 May 2020

function mpg = sort_cars(N)
load cars.mat
sorted = sortrows (cars,4);
mpg = sorted(1:N,2);
mpg{:,:}
end

Gives the correct output yet assertion failed. Why?

Solution 2226515

1 Comment

1 Comment

Diego Guisasola Plejo on 21 Apr 2020

This is an improved version of my code but still doesn't work:

function mpg = sort_cars(N)
S = load('cars.mat');
cars = struct2table(S)
B = sortrows(cars,2)
mpg = B.MPG(1:N)

end

Solution 2226463

4 Comments

4 Comments

Show 1 older comment

Diego Guisasola Plejo on 21 Apr 2020

I don't know why my solution is not working:

function mpg = sort_cars(N)
cars = load('cars.mat')
B = sortrows(cars,2)
mpg = B.MPG(1:N)
end

I tested it on the desktop version and it works flawlessly.
Any ideas, please?

Thanks in advance!

Derik Zhou on 7 May 2020

sortrows(cars, 2) supposed to be sortrows(cars, 4), Weight is on Column 4 I think.
Better be like this: sortrows(cars, 'Weight', 'ascend');

Tavish Pattanayak on 8 May 2020

mpg=mpg{:,:}

Add this to your code.

lin li on 20 Jul 2020

Hello.The output is expected to be a column vector, whereas your code returns a table. You may try extracting the vectors from the table, like this.
function mpg = sort_cars(N)
load cars.mat
W=sortrows(cars,'Weight')
mpg = W.MPG(1:N)
end

Solution 2213868

2 Comments

2 Comments

Gulo Mana on 16 Apr 2020

Comparison is equal, why assertion is failed?

Tavish Pattanayak on 8 May 2020

The output should be an array not a table.

Solution 2172277

3 Comments

3 Comments

Adetiloye Joseph Bamisebi on 24 Mar 2020

I do not understand why this code failed assertion test even though it yields the correct answer

function mpg = sort_cars(N)
load cars.mat
sorted = sortrows (cars,4)
n = N
mpg = sorted(1:n,2)
end

Pooja Lalan on 7 Apr 2020

The output is expected to be a column vector, whereas your code returns a table.

Prasad Reddy on 28 Apr 2020

I tried for the solution nearly 20 ways but didn't work. finally took help from the Matlab community and compleated it

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Problem 44952. Find MPG of Lightest Cars

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Problem 44952. Find MPG of Lightest Cars

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