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I have lon and lat and signal stengths plotting from my roaming GPS Lora module that reports signal strength to Thingspeak at it's location. I got GEOSCATTER plotting location circles.But i want extrapulate?Interp?Heatmap. the stengths between the points. When i use Interp i end up timiming out. How do i modify my code to do this?
Public Channel 214526
Cheers Andy
Spring is here in Natick and the tulips are blooming! While tulips appear only briefly here in Massachusetts, they provide a lot of bright and diverse colors and shapes. To celebrate this cheerful flower, here's some code to create your own tulip!
Hallo zusammen,
seit ein paar Tagen werden sämtliche meiner Visualisierungen nicht mehr aktualisiert. Im Editiermodus läuft der Code durch und die Grafik wird korrekt erzeugt.
Hat jemand eine Idee was da schief läuft?
Danke & viele Grüße
How to leave feedback on a doc page
Leaving feedback is a two-step process. At the bottom of most pages in the MATLAB documentation is a star rating.
Start by selecting a star that best answers the question. After selecting a star rating, an edit box appears where you can offer specific feedback.
When you press "Submit" you'll see the confirmation dialog below. You cannot go back and edit your content, although you can refresh the page to go through that process again.
Tips on leaving feedback
- Be productive. The reader should clearly understand what action you'd like to see, what was unclear, what you think needs work, or what areas were really helpful.
- Positive feedback is also helpful. By nature, feedback often focuses on suggestions for changes but it also helps to know what was clear and what worked well.
- Point to specific areas of the page. This helps the reader to narrow the focus of the page to the area described by your feedback.
What happens to that feedback?
Before working at MathWorks I often left feedback on documentation pages but I never knew what happens after that. One day in 2021 I shared my speculation on the process:
> That feedback is received by MathWorks Gnomes which are never seen nor heard but visit the MathWorks documentation team at night while they are sleeping and whisper selected suggestions into their ears to manipulate their dreams. Occassionally this causes them to wake up with a Eureka moment that leads to changes in the documentation.
I'd like to let you in on the secret which is much less fanciful. Feedback left in the star rating and edit box are collected and periodically reviewed by the doc writers who look for trends on highly trafficked pages and finer grain feedback on less visited pages. Your feedback is important and often results in improvements.
Drumlin Farm has welcomed MATLAMB, named in honor of MathWorks, among ten adorable new lambs this season!
Hi Helpdesk,
I urgently seek assistance with an issue that has persisted for a week. I am using Node-RED to interface my gateway and vibration sensor. The sensor sends 960 packets of X, Y, and Z data every 5 minutes. I retrieve and send this data through my Thingspeak42 node to my Thingspeak channel.
I am subscribed to the Thingspeak Student paid plan (see attached "12.png"). Despite this, Thingspeak is inconsistently snipping my data. For example, my X-field sometimes receives only 78 out of 960 points, and similar inconsistencies occur with the Y and Z fields.
Attached is "vibration data node red.png," showing an attempt to send just 120 packets to my Thingspeak channel. However, only 93 data points are received. Also attached is a JSON snapshot of field 2 - X_values, showing only 93 points ("JSON Field 2 data.png"). This is disappointing given that I am paying for the student plan, which should support 33 million points/year per unit (~90,000/day per unit).
I urgently require an explanation and resolution for this issue. Please provide immediate assistance.
Kind regards,
Krish
I have an Arduino Uno R3 with an integrated ESP 8266. With the Arduino Uno, I measure some capacitive humidity sensors and a DHT 22 temperature and humidity sensor. The measurements are sent to the serial port and the ESP 8266 picks them up and uploads them to ThingSpeak. My problem is that it does this randomly and not in the assigned fields. Could someone help me? Thank you very much
A colleague said that you can search the Help Center using the phrase 'Introduced in' followed by a release version. Such as, 'Introduced in R2022a'. Doing this yeilds search results specific for that release.
Seems pretty handy so I thought I'd share.
Bringing the beauty of MathWorks Natick's tulips to life through code!
Remix challenge: create and share with us your new breeds of MATLAB tulips!
Hi team,
Could you please confirm us about the process power and computational capacity of ThingSpeak i.e. how quickly and efficiently my MATLAB code can execute on ThingSpeak? What other specifications related to data communication and integration are there in ThingSpeak? As all specifications are not mentioned here: https://thingspeak.com/prices/thingspeak_academic
Thanks.
Regards,
Tanusree
WebSend zu "api.thingspeak.com" zeigt übermittelte Daten an, auf thingspeak kommt aber nichts an.
V11:54:37.665 SCR: performs "WebSend [api.thingspeak.com] /update,json?api_key=***&field1=14039.05&field2=35517.69&field3=-3986.00"
Hat jemand eine Idee warum?
I found this plot of words said by different characters on the US version of The Office sitcom. There's a sparkline for each character from pilot to finale episode.
From Alpha Vantage's website: API Documentation | Alpha Vantage
Try using the built-in Matlab function webread(URL)... for example:
% copy a URL from the examples on the site
URL = 'https://www.alphavantage.co/query?function=TIME_SERIES_DAILY&symbol=IBM&apikey=demo'
% or use the pattern to create one
tickers = [{'IBM'} {'SPY'} {'DJI'} {'QQQ'}]; i = 1;
URL = ...
['https://www.alphavantage.co/query?function=TIME_SERIES_DAILY_ADJUSTED&outputsize=full&symbol=', ...
+ tickers{i}, ...
+ '&apikey=***Put Your API Key here***'];
X = webread(URL);
You can access any of the data available on the site as per the Alpha Vantage documentation using these two lines of code but with different designations for the requested data as per the documentation.
It's fun!
This cheat sheet is here:
reference:
- https://github.com/peijin94/matlabPlotCheatsheet
- https://github.com/mathworks/visualization-cheat-sheet
- https://www.mathworks.com/products/matlab/plot-gallery.html
- https://www.mathworks.com/help/matlab/release-notes.html
MATLAB used to have official visualization-cheat-sheet, but there have been quite a few new updates in MATLAB versions recently. Therefore, I made my own cheat sheet and marked the versions of each new thing that were released :
Hi,
I'm a Analysis and systems development student.
Last friday i've created a GPS tracker, using thingspeak api and server, it was working fine until this morning, now it stops.
what could have happened?
i've not even touched the code these days
I isolated a var that I'm interested in, and I want to connect Node-RED to thingspeak to show the values on the graph. The problem is the node "mqttout": I connected it to the server mqtt3.thingspeak.com and the port 1883, and with the device with right username and password. It shows "connected", but the graph is still the same, I can not upload the varabiles.
Kindly assist. Im getting this error message when i try to upload to my esp8266 board. I have tried reinstalling arduino ide and libraries. Have also replaced my previous board with a new one.
" fatal esptool.py error occurred: Cannot configure port, something went wrong. Original message: PermissionError(13, 'A device attached to the system is not functioning.', None, 31)esptool.py v3.0
Serial port COM9"
I have noticed that any of thingspeak channels (irrespective of Public or private) can be read by using below request.
this reduces the security of the channel. If the channel is Private without the valid Read key it should not be able to read from the channel.
Am i missing something??
Temporary print statements are often helpful during debugging but it's easy to forget to remove the statements or sometimes you may not have writing privileges for the file. This tip uses conditional breakpoints to add print statements without ever editing the file!
What are conditional breakpoints?
Conditional breakpoints allow you to write a conditional statement that is executed when the selected line is hit and if the condition returns true, MATLAB pauses at that line. Otherwise, it continues.
The Hack: use ~fprintf() as the condition
fprintf prints information to the command window and returns the size of the message in bytes. The message size will always be greater than 0 which will always evaluate as true when converted to logical. Therefore, by negating an fprintf statement within a conditional breakpoint, the fprintf command will execute, print to the command window, and evalute as false which means the execution will continue uninterupted!
How to set a conditional break point
1. Right click the line number where you want the condition to be evaluated and select "Set Conditional Breakpoint"
2. Enter a valid MATLAB expression that returns a logical scalar value in the editor dialog.
Handy one-liners
Check if a line is reached: Don't forget the negation (~) and the line break (\n)!
~fprintf('Entered callback function\n')
Display the call stack from the break point line: one of my favorites!
~fprintf('%s\n',formattedDisplayText(struct2table(dbstack)))
Inspect variable values: For scalar values,
~fprintf('v = %.5f\n', v)
~fprintf('%s\n', formattedDisplayText(v)).
Make sense of frequent hits: In some situations such as responses to listeners or interactive callbacks, a line can be executed 100s of times per second. Incorporate a timestamp to differentiate messages during rapid execution.
~fprintf('WindowButtonDownFcn - %s\n', datetime('now'))
Closing
This tip not only keeps your code clean but also offers a dynamic way to monitor code execution and variable states without permanent modifications. Interested in digging deeper? @Steve Eddins takes this tip to the next level with his Code Trace for MATLAB tool available on the File Exchange (read more).
Summary animation
To reproduce the events in this animation:
% buttonDownFcnDemo.m
fig = figure();
tcl = tiledlayout(4,4,'TileSpacing','compact');
for i = 1:16
ax = nexttile(tcl);
title(ax,"#"+string(i))
ax.ButtonDownFcn = @axesButtonDownFcn;
xlim(ax,[-1 1])
ylim(ax,[-1,1])
hold(ax,'on')
end
function axesButtonDownFcn(obj,event)
colors = lines(16);
plot(obj,event.IntersectionPoint(1),event.IntersectionPoint(2),...
'ko','MarkerFaceColor',colors(obj.Layout.Tile,:))
end
I have a LORA node up-linking data to a Thingspeak channel via The Things Network (TTN). Sometimes it stops sending data and I reboot it by logging into my console on TTN and sending a re-boot down-link message to the node. Is there any way I can transmit a downlink message to the node direct from Thinkspeak?
