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Elija
Elija
Last activity 2024 年 2 月 14 日

Hello, all!
This is my first post after just joining this discussion, so please forgive me and provide kind assistance if I have posted to the wrong subsection!
I have a good interest in learning sql server course and right now I am taking help from various platforms like https://www.coursera.org/ https://www.udemy.com/
Also I have a doubt that is it a good option to learn from platforms like this or I should go for some sql server online training . I have searched for the solution of my queries in various above platforms which helped me up to some extent only as it was not directly given by any expert or trainer.
Hoping in getting a quick response
Thankyou in advance.
Emma Farnan
Emma Farnan
Last activity 2023 年 11 月 28 日

I think it would be a really great feature to be able to add an Alpha property to the basic "Line" class in MATLAB plots. I know that I have previously had to resort to using Patch to be able to plot semitransparent lines, but there are also so many other functions that rely on the "Line" class.
For example, if you want to make a scatter plot from a table with things specified into groups, you can use ScatterHistogram or gscatter but since gscatter uses the Line class, you can't adjust the marker transparency. So if you don't want the histograms, you are stuck with manually separating it and using scatter with hold on.
I saw this post on Answers.
I was impressed at the capability of the AI, as I have been at other times when I posed a question to it, at least some of the time. So much so that I wondered...
What if the AI were automatically applied to EVERY question on Answers? Would that be a good or bad thing? For example, suppose the AI automatically offers an answer to every question as soon as it gets posted? Of course, users would still be allowed to post their own, possibly better answers. But would it tend to disincentivise individuals from ansering questions?
Perhaps as bad, would it push Answers into the mode of a homework solving forum? Since if every homework question gets a possibly pretty good automatic AI generated solution, then every student will just post all HW questions, and the forum would quickly become overwhelmed.
I suppose one idea could be to set up the AI to post an answer to all un-answered questions that are at least one month old. Then students would not gain by posting their homework.
Mishal Mohanlal
Mishal Mohanlal
Last activity 2023 年 11 月 17 日

Hi Guys
Posting this based on a thought I had, so I don't really ahve any code however I would like to know if the thought process is correct and/or relatively accurate.
Consider a simple spring mass system which only allows compression on the spring however when there is tension the mass should move without the effect of the spring distrupting it, thus the mass is just thrown vertically upwards.
The idea which I came up with for such a system is to have two sets of dfferential equations, one which represents the spring system and another which presents a mass in motion without the effects of the spring.
Please refer to the below basic outline of the code which I am proposing. I believe that this may produce relatively decent results. The code essentially checks if there is tension in the system if there is it then takes the last values from the spring mass differential equation and uses it as initial conditions for the differential equation with the mass moving wothout the effects of the spring, this process works in reverse also. The error which would exist is that the initial conditions applied to the system would include effects of the spring. Would there be a better way to code such behaviour?
function xp = statespace(t,x,f,c,k,m)
if (k*x(1)) positive #implying tension
**Use last time step as initial conditions**
**differential equation of a mass moving""
end
if x(1) negative #implying that the mass in now moving down therefore compression in spring
**Use last time step as initial conditions**
**differential equation for a spring mass system**
end
end
Seeing a colleague make this mistake (one I've had to fix multiple times in other's work too) makes me want to ask the community: would you like the awgn() function/blocks to give the option for creating a SNR at the bandwidth of the signal? Your typical flow is something like this:
  • Create a signal, usually at some nominal upsampling factor (e.g., 4) such that it's now nicely over sampled, especially if you're using a RRC or similar pulse shaping filter.
  • Potentially add a frequency offset (which might make the sample frequency even higher)
  • Add AWGN channel model for a desired SNR
  • Put this into your detector/receiver model
The problem is, when someone says, "I'm detecting XYZ at foo SNR," it should not magically improve as a function of the oversample. The problem isn't that awgn() generates white noise, that's what it's supposed to do and the typical receiver has noise across the entire band. The problem is that SNR is most properly defined as the signal power over the noise power spectral density times the signal's noise equivalent bandwidth. Now I looked and there's no handy function for computing NEBW for an input signal (there's just a function for assessing analysis windows). In practice it can get a bit tricky. The occupied bandwidth or HPBW are often close enough to the NEBW, we're usually not haggling over hundredths of a dB. So, in my not so humble opinion, the "measured" flag for awgn() should give an option for bandwidth matching or at least document the behavior better in the help page. All too often I'm seeing 3-6 (or worse) dB errors because people aren't taking the signal's bandwidth into account.
The MATLAB AI Chat Playground is open to everyone!
Check it out here on the community: https://www.mathworks.com/matlabcentral/playground
MATLAB AI Chat Playground Screenshot
I just published a blog post announcing the release.
Julian
Julian
Last activity 2024 年 2 月 5 日

I know the latest version of MATLAB R2023b has this feature already, put it should be added to R2023a as well because of its simplicity and convenience.
Basically, I want to make a bar graph that lets me name each column in a basic bar graph:
y=[100 99 100 200 200 300 500 800 1000];
x=["0-4" "5-17" "18-29" "30-39" "40-49" "50-64" "65-74" "75-84" "85+"];
bar(x,y)
However, in R2023a, this isn't a feature. I think it should be added because it helps to present data and ideas more clearly and professionally, which is the purpose of a graph to begin with.
Matt J
Matt J
Last activity 2024 年 3 月 1 日

Would it be a good thing to have implicit expansion enabled for cat(), horzcat(), vertcat()? There are often situations where I would like to be able to do things like this:
x=[10;20;30;40];
y=[11;12;13;14];
z=cat(3, 0,1,2);
C=[x,y,z]
with the result,
C(:,:,1) =
10 11 0
20 12 0
30 13 0
40 14 0
C(:,:,2) =
10 11 1
20 12 1
30 13 1
40 14 1
C(:,:,3) =
10 11 2
20 12 2
30 13 2
40 14 2
In the past year, we've witnessed an exponential growth of ChatGPT and other Generative AI tools. AI has quickly become a transformative force across industries, from tech giants to small startups, and even community sites like ours. For instance, Stack Overflow announced its plan to leverage AI tools to draft a question or tag content; Quora built a ChatGPT bot to answer questions; and GitHub is piloting the AI tool for personalized content.
This trend in the community landscape makes me wonder what MATLAB Central community, especially in MATLAB Answers, can do to integrate AI and enhance the community.
Share with us your ideas in the comment session. Ideally one comment per idea, so that others can vote on a secific idea or have deeper discussions about it.
We launched the Discussions area with 6 channels, based on the existing types of content we see today in the MATLAB Central community.
I'm curious which channels you are most interested in participating, or which channels are missing.
Tell us your thoughts here!
This person used computer version to build a keyboard input, and used standard flag semaphore for the positions.
Flag semaphore is used mostly by sailors to be able to communicate optically over a distance; it does not need anything more than make-shift flags (but binoculars or telescopes can help.) Trained users can go faster than you might guess.
Hans Scharler
Hans Scharler
Last activity 2024 年 7 月 27 日

Chen, Rena, and I are at a community management event. It's great to be with others talking about relationships, trust, and co-creation.
Walter Roberson
Walter Roberson
Last activity 2023 年 12 月 27 日

A research team found a way to trick a number of AI systems by injecting carefully placed nonsense -- for example being able able to beat DeepMind's Go game.
This video discusses the "Cody" bridge, which is a pedestrian bridge over a canal that has been designed to move up and out of the way when ships need to travel through. The mathematics of the bridge movement are discussed and diagrammed. It is unique and educational.
Walter Roberson
Walter Roberson
Last activity 2023 年 10 月 4 日

Recently developed: a "microscope" based on touch and stereo vision.
Using touch removes the possibility of optical confusion -- for example, black on touch is only due to shape, not due to the possibility that the object has a black patch.
Sorry, you might need a Facebook account to watch the video.
Rik
Rik
Last activity 2024 年 2 月 7 日

This is the 6th installment of the wish-list and bug report thread.
This topic is the follow on to the first Wish-list for MATLAB Answer sections and second MATLAB Answers Wish-list #2 (and bug reports). The third started out as New design of the forum - grey on white and the fourth and fifth also grew so large they are slow to load and navigate.
Same idea as the previous ones: one wish (or bug report) per answer, so that people can vote their wishes.
What should you post where?
Wishlist threads (#1 #2 #3 #4 #5 #6): bugs and feature requests for Matlab Answers
Frustation threads (#1 #2): frustations about usage and capabilities of Matlab itself
Missing feature threads (#1 #2): features that you whish Matlab would have had
Next Gen threads (#1): features that would break compatibility with previous versions, but would be nice to have
@anyone posting a new thread when the last one gets too large (about 50 answers seems a reasonable limit per thread), please update this list in all last threads. (if you don't have editing privileges, just post a comment asking someone to do the edit)
Antonello Zito
Antonello Zito
Last activity 2024 年 11 月 4 日 0:57

This is not a question, but a point of discussion for the entire community. I am aware that every 1/2 months this theme comes out, but until this is not fixed it is totally necessary that this comes, indeed, out. And I said "fix" because Mathworks has to understand that a dark theme is not only a visual/aesthetic matter, it is a substantial part of the game. Most of the OS, GUIs, programs are actually in dark mode, and a vast majority of the users makes indeed use of a global dark mode. How much one does like it is personal, but the benefits to power savings and eye health is instead a fact. Mathworks being ignoring this for years is nothing but ridiculous. Of course it is not an easy task, but every minute of committment for it is worthy. And nope, Schemer is not helpful because it does not provide a real fix to this question.
I feel free to suggest something similar to the Spyder's dark theme, which came out like 2 years ago if I remember correctly.
Of course, my point is not being disrespectful (I am instead very respectful to the huge efforts of Mathworks for making this wonderful program run). But, form a user's point of view, the fact that not a single word has so far come out from Mathworks about a dark theme (meaning that for sure we will not see it in a timing of months) requires us to put a strong pressure on this.
Mathworks, please: it's time for a dark theme.
Let's say MathWorks decides to create a MATLAB X release, which takes a big one-time breaking change that abandons back-compatibility and creates a more modern MATLAB language, ditching the unfortunate stuff that's around for historical reasons. What would you like to see in it?
I'm thinking stuff like syntax and semantics tweaks, changes to function behavior and interfaces in the standard library and Toolboxes, and so on.
(The "X" is for major version 10, like in "OS X". Matlab is still on version 9.x even though we use "R20xxa" release names now.)
What should you post where?
Wishlist threads (#1 #2 #3 #4 #5): bugs and feature requests for Matlab Answers
Frustation threads (#1 #2): frustrations about usage and capabilities of Matlab itself
Missing feature threads (#1 #2): features that you whish Matlab would have had
Next Gen threads (#1): features that would break compatibility with previous versions, but would be nice to have
@anyone posting a new thread when the last one gets too large (about 50 answers seems a reasonable limit per thread), please update this list in all last threads. (if you don't have editing privileges, just post a comment asking someone to do the edit)
Is anyone else disappointed with uifigures? It seems apparent that these will eventually replace traditional figures, but there is still so much that doesn't quite work. I've tinkered with uifigures since their introduction in release 2016a, but even in 2020a I can't reliably export a uifigure to a graphics file. Sure it works sometimes, but not if a uipanel is present. The exportgraphics command is not as powerful as the print command, leaving some graphic formats (such as *.svg and *.eps) unsupported. How do you generate graphic files of a specific size? You can't even use subplots without overriding the default AutoResizeChildren setting!
Everything with uifigures seems to be slower and less stable than the figure variant. App Designer is much better than GUIDE, but that is not exactly high praise. I would rather generate "apps" programatically across several files instead of dealing with a single-file class definition containing 1000+ lines.
Where is this transition going? MATLAB graphics are moving away from Java in favor of JavaScript, and I'm not sure that we are at all ready for that.