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Is there a way via MQTT to access the talkback. I want to read the talkback variable using MQTT and not REST. I have a ESP8266 which I am logging data, but also have a relay which I want to switch. I am using MQTT to log the data, but don't wanna use REST to access/read the talkback. Hope there is a way which I missed. Thanks so long.

One of the objectives of lab-based instruction can be to develop students’ familiarity with hardware equipment. When students could no longer come to their lab in person, educators at HTW Dresden developed a MATLAB app using App Designer to replicate the controls on lab equipment such as a signal generator and oscilloscope. Read this article to learn more about how Dr. Henker and Dr. Kelber virtualized their electrical engineering labs.

If you use Simulink or Simscape models for your virtual labs, you can create an interactive display of controls and displays within your model diagram using blocks from the Dashboard library. To do so, connect block parameters to control blocks (knobs, buttons, and switches) and signals to displays blocks (scopes and gauges).

New customizable Knob, Vertical Slider, and Horizontal Slider blocks introduced in R2021a let you choose your own background image, foreground image, handle or slider image, and scale appearance. By combining these with custom gauge blocks, you can create intuitive and photo-realistic dashboards for interacting with your models, such as in the image below.

View examples of controlling simulations with interactive displays, or read some more Tips for Moving your Lab-based Classes Online.

Hello everyone. Yesterday i started my project and now im trying to export data files (CSV) but it is empty. It cointains just the headers and last read (i think). Anyone knows what is happening?

Example CSV exported created_at,entry_id,field1,field2,field3,latitude,longitude,elevation,status 2021-05-26 19:39:23 -03,1,25.00,"43.00

",,,,, 2021-05-26 19:39:39 -03,2,24.80,40.00"

I am trying to simulate the PMSM in fault mode with phase loss at 0.25 sec, but the simulation results are incorrect. For example, the rotor speed changes too much when a phase is missing. I tried to assemble the model in dq coordinates and abc coordinates on my own, but the results are the same. Who can tell you how to modify the engine model so that the simulation shows the correct results?

ThingSpeak includes an integration with The Things Stack to support collection of data over a long range network. I made a short presentation for this upcoming conference that shows you how to add the ThingSpeak integration to your Things Stack project. The agenda seems to be filled with other useful IoT talks. Here is the information on the conference:

Discover the next-generation #LoRaWAN deployments at The Things Stack Conference. Explore advanced LoRaWAN features, cloud integrations and the next-generation #IoT devices at #TheThingsConference - TheThings Stack Edition, online on 28 May 2021!

Registrations are now open: – ow.ly/I1PZ30mNt0I

#TheThingsConference #TheThingsNetwork #LoRaWAN

If you go and see something you like, please feel free to share in this discussion.

Starting in MATLAB R2021a axis tick labels will auto-rotate to avoid overlap when the user manually specifies ticks or tick labels ( release notes ). In custom visualization functions, the tick label density or tick label lengths may be variable and unknown. The new auto-rotation feature removes the burden of detecting the need to rotate manually-set labels and eliminates the need to manually rotate them.

Many properties and combinations of properties can cause tick labels to overlap if they are not rotated.

• Length of tick labels
• Number of tick labels
• Interval between tick labels
• Font size
• Font name
• Figure size
• Axes size
• Viewing angle of the axes

Demo: varying tick density and length of tick labels

These 9 axes vary by the number of x-ticks and length of x-tick-labels. MATLAB auto-rotates the labels when needed.

Demo: Changes to axis view angle and rotation

The auto-rotation feature updates the label angles as the axes change programmatically or during user interaction.

What if I don't want auto-rotation?

Auto-rotation mode is on by default for each X|Y|Z axis. When the tick label rotation angle is manually set from the X|Y|ZTickLabelRotation property of axes or by using xtickangle | ytickangle | ztickangle , auto-rotation is turned off. Auto-rotation can also be turned off by setting the X|Y|ZTickLabelRotationMode axis property to manual but it's important to also hold the axis properties so that the rotation mode does not revert to the default value, auto. If you're looking for a broader method of reverting to older behavior you can set the default label rotation mode to manual at the start of a function that produces multiple plots and then revert to the factory default rotation mode at the end of the file (consider using onCleanup).

set(groot,'defaultAxesXTickLabelRotationMode','manual')
set(groot,'defaultAxesYTickLabelRotationMode','manual')
set(groot,'defaultAxesZTickLabelRotationMode','manual')

% Revert to factory-default
set(groot,'defaultAxesXTickLabelRotationMode','remove')
set(groot,'defaultAxesYTickLabelRotationMode','remove')
set(groot,'defaultAxesZTickLabelRotationMode','remove')

A copy of this Community Highlight is attached as a live script.

'nanmean' requires one of the following: Financial Toolbox Statistics and Machine Learning Toolbox

Error in Custom (no starter code) 1 (line 15) avghumidity= nanmean(humidity);

how to remove this error?

If you teach ordinary differential equations (ODEs) or use ODEs in your class, a common challenge you may have encountered is helping your students overcome the ‘mathematical intimidation’ of the concepts. You can use the Phase Plane and Slope Field apps, developed and shared by the MathWorks Online Teaching team, to let your students develop a visual intuition of ODEs by qualitative analysis.

These apps capture the functionality of the wildly popular PPlane and DField apps created by John C. Polking in MATLAB between 1995 and 2003. While similar in function to the original apps, the Slope Field and Phase Plane apps have been written entirely from scratch in MATLAB App Designer using modern MATLAB coding practices. This makes the new apps easier to maintain, edit, and use.

Get the apps on GitHub, and visit the MATLAB and Simulink Courseware page for more curriculum resources tailored to multiple disciplines.

Via a particle photon and webhook, i am sending data to THINGSPEAK. The channel indicates entries e.g. 1239 entries but the graphs are empty. Can anyone help me to fix this? Thanks

Hi, I have an AIOT project on vertical farming project. Currently, I am using Thingspeak to store sensor values. I am planning to do the followings:

1) do an analysis on the data collected for each sensors on their max, min and median (50%) to determine that the sensor value is currently ok for the plants. I am aware that Thingspeak is able to calculate these and I am learning about this now.

2) I would like to predict the sensor values collected ( eg temperature/humidity etc). I feel that this is a cool feature to have in my project but I am not sure how do I go about this. For experts in Thingspeak, do you think this is a must have for an internship project on vertical farming and how do I apply this in my project? I am not sure if this is manageable for a single student to do this and I really appreciate it if anyone would guide me along.

Hallo all Did anyone tried to send data from siemens wincc scada to a chanell. From me experiance wincc VBA works but from wincc VBS no way? Any comment or experiance to share

MATLAB, Simulink, and their support for a variety of low-cost hardware has allowed many students to continue benefit from project-based learning, even from their own homes. Popular choices include the Arduino Engineering Kit and Raspberry Pi.

If you use or are considering using Raspberry Pi for your class, your students could benefit from using the Raspberry Pi Resource Monitor App. This app, introduced in MATLAB R2020b, will allow them to graphically configure target boards, deploy Simulink models and MATLAB functions, manage peripheral devices and interfaces, and perform common troubleshooting steps. Such an approach can simplify many of the technical challenges faced by educators who adopt a ‘Hardware at Home’ approach for their lab-based classes.

Click here to learn more about Raspberry Pi support from MATLAB and Simulink.

You may also want to learn more about Virtual Labs and Projects with MATLAB and Simulink, or read some Tips for Moving your Lab-based Classes Online.

Our ThingSpeak channels stopped updating their dashboards at 20:08 BST. We can see other public channels aren't updating too from this time.

Our code for writing to ThingSpeak is returning a 202 success, indicating it is successful, suggesting that data is still being written.

Are any ThingSpeak services down?

When I log in to my account the display just constantly cycles/refreshes about every 2 seconds, with a message at the top saying "authenticating". So I can't view anything.

I can't edit charts with the pencil icon, tried different sort of webbrowsers in windows 10 and also different pc's. When i try it on my android phone it does work perfectly with the same wifi connection? When i inspect the pencil object in the chrome browser it shows some warnings, see picture

Hello, I want to read the instant GPS data from Thingspeak Cloud and show it on the folium map, but I could not do the integration. Do you have Any suggestions?

Four (of many) new features for Apps in MATLAB R2021a

These four new features are the solutions to many inquiries in the Answers forum that continue to receive hundreds of views per month long after they were asked.

Table of Contents

• Keyboard Shortcuts for UI Components
• Programmatically scroll UITables
• Figure always on top
• UI hyperlink component
• Demo app: Keyboard shortcut challenge

Keyboard Shortcuts for UI Components

Keyboard shortcuts can now change the focus and make contiguous and non-contiguous selections in ListBox, Table, DatePicker, and ColorPicker menus created in uifigures. The table below summarizes the shortcuts made available in R2021a ( release notes ).

Reminder: in MATLAB R2020b and later you can change the tab order of objects in an app by changing their stack order in AppDesigner using the Reorder tool in the drop-down menu or by right-clicking the component and selecting Reorder from the menu (see R2020b release notes and a screenshot in the Answers forum ).

Programmatically scroll UITables

The scroll function was added in R2016a but as of R2021a it can be used with uitables to programmatically scroll to the top, bottom, left, or right of a table or to a specific row, column or cell ( release notes ). Combined with a uistyle (R2019b) you can scroll to and highlight any part of the uitable.

Syntax examples:

• scroll(uit,vlocation) where vlocation is 'top'-'bottom'
• scroll(uit,hlocation) where hlocation is 'left'-'right'
• scroll(uit,target,targetIndex) where target is 'row'-'column'-'cell' and targetIndex is a row or column number or a 1x2 cell location.

Figure always on top

Figures created with uifigure now have an additional WindowStyle property: 'alwaysontop' ( release notes ). Figures with this setting will stay on top of other windows but unlike the modal option, other windows are still accessible.

See the WindowStyle property description for tips on setting and changing this property.

To toggle the AlwaysOnTop state of your app using a checkbox, state button, or another UI component, follow this callback function template,

function alwaysOnTopCheckBoxValueChanged(app, event)
    value = app.alwaysOnTopCheckBox.Value;
    if value
        app.UIFigure.WindowStyle = 'alwaysontop';
    else
        app.UIFigure.WindowStyle = 'normal';
    end
end

UI hyperlink component

Use the uihyperlink function or the UI hyperlink component in App Designer or a uifigure to add and configure a clickable link ( release notes ). The hyperlink can be assigned to a figure, panel object, tab object, ButtonGroup, or GridLayout object when created in a uifigure. In addition to setting the text and URL, there are lots of properties to control the text format including the VisitedColor property that controls the color of the text after the link is clicked and an optional user-defined HyperlinkClickedFcn function that is evoked when the link is clicked.

Demo app: Keyboard shortcut challenge

The attached zip file contains an app, keyboardShortcutsDemo_R2021a.mlapp , that demonstrates these 4 features. The app displays the extent of arctic sea ice from 1979 to 2016 during the months when extent typically maximizes and minimizes.

Mouseless challenge: After opening the app, without using your mouse, try the following.

• Select a month (September or March) and any number of years from the list boxes
• Navigate through the Date Picker and select a date within the range or your selected years (disabled when only 1 year is selected).
• Navigate to the always-on-top checkbox to pin the app to the top of other windows.
• Navigate to the text box and enter a year that appears in the uitable to go to that row in the uitable (disabled when only 1 year is selected).
• Navigate to the URL and press Enter to open the website containing the raw data.

Download the attached zip file, FourNewAppFeatures_R2021a.zip, for a Live script copy of this thread and an app that demonstrates each feature.

Hello, was hoping to share my Public Sharing page with others without the need for them to log in. In Chrome, it works only if I open a page in Incognito Mode, then I can view without logging in.

Also, from FB Messenger, I can click the link and it will open a page on my Iphone without needing login, but some others, including me in Chrome click the link and it says I need to log in first.

Any ideas how to fix that?

MATLAB EXPO 2021 was held earlier this week. This global online event featured presentations and hands-on workshops covering topics from AI, to Application Deployment, and from Algorithm Development, to Teaching with MATLAB and Simulink. Dr. Magnus Egerstedt, Steve W. Chaddick School Chair and Professor of Electrical and Computer Engineering at Georgia Institute of Technology, spoke about Robotarium - a remotely accessible swarm robotics lab that remains freely accessible to anyone.

Robotarium allows users from all over the world to upload control code written in MATLAB and run experiments. Creating a swarm robotics lab is resource intensive, so such a remote access solution can be a great alternative. Watch Prof. Egerstedt introduce Robotarium.

You may also want to learn more about Virtual Labs and Projects with MATLAB and Simulink, or read some Tips for Moving your Lab-based Classes Online. If you are in China, Japan, or Korea, click here to register for dedicated EXPO events this summer.

Hi!Yersterday i finally connected my rpi 3B+ with sensehat via Thingspeak.All worked just fine but today when i started the stream(run-prod.sh) number of entries appeared stuck on 0.I created a new channel but the problem still persist.If someone could help much obliged.P.S is a project for faculty.Any help would be helpfull.

Regards, Andrei.