MATLAB Central Discussions - Join the conversation!
メインコンテンツ

Results for


MATLAB Onramp is a free online tutorial and it has been very popular with new MATLAB users to learn how to use it, and MathWorks have been adding more and more modules. The lastest one just dropped https://matlabacademy.mathworks.com/details/power-systems-simulation-onramp/orps
It shows you the basics of power system simulation by modeling a simple microgrid. You will learn how to simulate and measure three-phase circuits, and how to evaluate algorithms like droop control and maximum power point tracking.
Thats the task:
Given a square cell array:
x = {'01', '56'; '234', '789'};
return a single character array:
y = '0123456789'
I wrote a code that passes Test 1 and 2 and one that passes Test 3 but I'm searching a condition so that the code for Test 3 runs when the cell array only contains letters and the one for Test 1 and 2 in every other case. Can somebody help me?
This is my code:
y = []
[a,b]=size(x)
%%TEST 3
delimiter=zeros(1,a)
delimiter(end)=1
delimiter=repmat(delimiter,1,b)
delimiter(end)=''
delimiter=string(delimiter)
y=[]
for i=1:a*b
y = string([y x(i)])
end
y=join(y,delimiter)
y=erase(y,'0')
y=regexprep(y,'1',' ')
%%TEST 1+2
for i=1:a*b
y = string([y x(i)])
y=join(y)
end
y=erase(y,' ' )
Here's a screenshot from 22 years ago. Thanks for building one of the best engineering and science communities together.
Mayla
Mayla
Last activity 2023 年 9 月 13 日

That's the question: Given four different positive numbers, a, b, c and d, provided in increasing order: a < b < c < d, find if any three of them comprise sides of a right-angled triangle. Return true if they do, otherwise return false .
I wrote this code but it doesn't pass test 7. I don't really understand why it isn't working. Can somebody help me?
function flag = isTherePythagoreanTriple(a, b, c, d)
a2=a^2
b2=b^2
c2=c^2
d2=d^2
format shortG
if a2+b2==c2
flag=true
else if a2+b2==d2
flag=true
else if a2+c2==d2
flag=true
else if c2+b2==d2
flag=true
else flag=false
end
end
end
end
end
Mayla
Mayla
Last activity 2023 年 10 月 24 日

That's the question:
The file cars.mat contains a table named cars with variables Model, MPG, Horsepower, Weight, and Acceleration for several classic cars.
Load the MAT-file. Given an integer N, calculate the output variable mpg.
Output mpg should contain the MPG of the top N lightest cars (by Weight) in a column vector.
I wrote this code and the resulting column vector has the right values but it doesn't pass the tests. What's wrong?
function mpg = sort_cars(N)
load cars.mat
sorted=sortrows(cars,4)
mpg = sorted(1:N,2)
end
cities
15%
beaches, islands, or cruises
22%
rivers, lakes, or mountains
33%
National Parks or historical sites
14%
wherever my family lives
12%
somewhere else
5%
13709 票
Hello, an intern working at MathWorks is finishing up his program soon and he would like to interview some MATLAB users. He is looking for people who can give their perspective on the question:
"What makes MATLAB and Simulink special in comparison to other languages?"
Ultimately he plans to condense the answers into 15-second videos or sound bites.
If people are willing to participate but want more time to talk about their experience with MATLAB, he doesn't have time left for in-depth interviews but he can find someone else to take over the project.
Please send me an email via my profle if you are interested.
Yes, in my company that I own
35%
Yes, for someone else (or Univ.)
21%
Only for free, for charities
13%
Only in my charitable foundation
5%
No, I'd just play, travel, & relax
25%
15668 票
1
33%
2
34%
3
18%
4
5%
5
3%
6+
6%
1643 票
Image Analyst
Image Analyst
Last activity 2023 年 8 月 19 日

half full.
12%
half empty.
4%
both.
12%
twice as big as it needs to be.
15%
1/2 full of beer, 1/2 full of air.
17%
What glass???
39%
6618 票
I recently have found that I am no longer able to give my difficulty rating for questions on Cody after sucessfully completing a question. This is obviously not a big deal, I was just wondering if this was an issue on my end or if there was some change that I was not aware of.
The option to rate does not pop up after solving a problem, and the rating in general does not even show up anymore when answering questions (though it is visible from problem groups).
figure out what my old code does
18%
write code comments for future me
11%
address a code analyzer warning
3%
reflect on the skills I've gained
8%
get food on my mouse and keyboard
38%
All of the above
22%
16434 票
Getting Started with Simulink | Tips and Tricks to Get the Most Out of Simulink
Watch live as Tianyi Zhu and Ashwin Dhawad walk through how you can get started with Simulink by modeling, simulating, and tuning a PID controller for a DC Motor. This session isn’t just for beginners; they will show you the latest and greatest tips and tricks to help you get the most out of Simulink.
Date & Time: May 25, 2023 at 11:00 am EDT (see time in your time zone)
MATLAB Central has been great community-based MATLAB resources, but you can now access its content programmatically via the public API, and I created a MATLAB function to take advantage of that. You can learn more here https://api.mathworks.com/community
Example:
data = searchMATLABCentral("plotting",scope="matlab-answers",sort_order="created desc",created_after=datetime("2023-01-01"));
T = struct2table(data.items);
T(:,["created_date","title","is_answered"])
Output
Function
function results = searchMATLABCentral(query,options)
% SEARCGMATLABCENTRAL retrieves content of the MATLAB Central for a given
% query and returns the result as a struct.
% The function uses MathWorks RESTful API to search for content.
% The API is rate limited via IP throttling. No authentication is required.
% See API documentation for more details https://api.mathworks.com/community
%
% Input Arguments:
%
% query (string) - Required. The search query string.
% scope (string) - Optional. Specify the artifact. If not specified,
% the scope defaults to 'matlab-answers'.
% Other options include 'file-exchange','blogs','cody',
% 'community-highlights', and 'community-contests'.
% tags (string) - Optional. Specify a comma-separated list of tags.
% created_before (datetime) - Optional. Specify the last date in the results
% created_after (datetime) - Optional. Specify the first date in the results
% sort_order (string) - Optional. Speficy the order of the results.
% If not specified, it defaults to "relevance desc".
% Other options include 'created asc', 'created desc',
% 'updated asc','updated desc', 'relevance asc',
% and 'relevance desc'.
% page (integer) - Optional. Specify the page to retrieve.
% If the 'has_more' field in the result is positive,
% increment this argument to retrieve the next page.
% count (integer) - Optional. Specify the number of results as a value
% between 1 and 50; The default is 10.
%
% Output Arguments:
%
% results (struct) - Structure array containing the results of the search.
% validate input arguments
arguments
query string {mustBeNonzeroLengthText,mustBeTextScalar}
options.scope string {mustBeMember(options.scope,["matlab-answers", ...
"file-exchange","blogs","cody","community-highlights", ...
"community-contests"])} = "matlab-answers";
options.tags string {mustBeNonzeroLengthText,mustBeVector}
options.created_before (1,1) datetime
options.created_after (1,1) datetime
options.sort_order string {mustBeMember(options.sort_order,["created asc", ...
"created desc","updated asc","updated desc","relevance asc","relevance desc"])}
options.page double {mustBeInteger,mustBeGreaterThan(options.page,0)}
options.count double {mustBeInteger,mustBeInRange(options.count,1,50)}
end
% API URL and endpoint
url = "https://api.mathworks.com/community";
endpoint = "/v1/search";
% convert MATLAB datetime to the internet datetime format string
if isfield(options,"created_before")
options.created_before = string(options.created_before,"yyyy-MM-dd'T'HH:mm:ss'Z'");
end
if isfield(options,"created_after")
options.created_after = string(options.created_after,"yyyy-MM-dd'T'HH:mm:ss'Z'");
end
% convert optional inputs into a cell array of key-value pairs
keys = fieldnames(options);
vals = struct2cell(options);
params = [keys,vals].';
% call the API
try
results = webread(url+endpoint,"query",query,params{:});
catch ME
rethrow(ME)
end
end
Congratulations, @John D'Errico for winning the Editor's Pick badge awarded for MATLAB Answers, in recognition of your awesome solution in What to be chosen c so that all elements of matrix B will be a round number. B=A.c; where A is the matrix of non integers. The OP has not accepted his answer yet, but
As with other nominated answers, you provided detailed explanation with examples to show that what the OP is looking for may not be possible in some cases.
Unfortunately, you can only get this badge once - perhaps this raises a question about how this award should work. In any case, we nonetheles appreciate your ongoing effort to help other users in the community. Thnk you so much!
MATLAB Central Team
Object Detection and Tracking using Computer Vision
In this event, Matt and Megan show you how to perform one or the more difficult task in computer vision: tracking multiple objects.
They will walk through an example from the new Coursera specialization, Computer Vision for Engineering and Science. The code and video used in the example are available to those who sign up for the specialization.
Date & Time: May 11, 2022 at 11:00 am EDT (see time in your time zone)
AI
22%
Wireless Connectivity and Radar
4%
Autonomous Systems and Robotics
15%
Cloud, Enterprise, and DevOps
2%
Algorithms and Data Analytics
17%
Modeling and Simulation
36%
179 票
<= 6 GB
10%
7–12 GB
26%
13–22 GB
34%
23–46 GB
19%
47–90 GB
6%
>= 91 GB
6%
15925 票
Yes, the available tools are great
12%
Yes, the available tools need help
6%
No, but I would like to
14%
No, it is not important to me
7%
What is test-driven development?
61%
1955 票
Always
12%
Sometimes
11%
In the past, but not now
3%
Never
20%
What is Simulink Project?
53%
2443 票
Go to top of page