Resultados de
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I keep getting this error, what do I do?
Error: File: convert_mnist_to_mat.m Line: 63 Column: 1
This statement is not inside any function.
(It follows the END that terminates the definition of the function
"read_mnist_labels".)
function convert_mnist_to_mat(mnist_dir, output_file)
% Function to convert MNIST dataset files into .mat format
% Check if the directory exists
if ~isfolder(mnist_dir)
error('MNIST directory does not exist.');
end
% Read training images
train_images = read_mnist_images(fullfile(mnist_dir, 'train-images-idx3-ubyte'));
% Read training labels
train_labels = read_mnist_labels(fullfile(mnist_dir, 'train-labels-idx1-ubyte'));
% Read test images
test_images = read_mnist_images(fullfile(mnist_dir, 't10k-images-idx3-ubyte'));
% Read test labels
test_labels = read_mnist_labels(fullfile(mnist_dir, 't10k-labels-idx1-ubyte'));
% Save data into .mat file
save(output_file, 'train_images', 'train_labels', 'test_images', 'test_labels');
disp('MNIST dataset converted successfully.');
end
function images = read_mnist_images(filename)
% Function to read MNIST image data
fid = fopen(filename, 'rb');
assert(fid ~= -1, ['Could not open ', filename, '']);
magic_number = fread(fid, 1, 'int32', 0, 'ieee-be');
assert(magic_number == 2051, ['Invalid magic number in ', filename]);
num_images = fread(fid, 1, 'int32', 0, 'ieee-be');
num_rows = fread(fid, 1, 'int32', 0, 'ieee-be');
num_cols = fread(fid, 1, 'int32', 0, 'ieee-be');
images = fread(fid, [num_rows, num_cols, num_images], 'uint8');
fclose(fid);
images = permute(images, [2, 1, 3]); % Convert from (rows, cols, images) to (cols, rows, images)
end
function labels = read_mnist_labels(filename)
% Function to read MNIST label data
fid = fopen(filename, 'rb');
assert(fid ~= -1, ['Could not open ', filename, '']);
magic_number = fread(fid, 1, 'int32', 0, 'ieee-be');
assert(magic_number == 2049, ['Invalid magic number in ', filename]);
num_labels = fread(fid, 1, 'int32', 0, 'ieee-be');
labels = fread(fid, [num_labels, 1], 'uint8');
fclose(fid);
end
% Usage example:
mnist_dir = 'C:\Users\gabep\Desktop\MNIST';
output_file = 'mnist_dataset.mat';
convert_mnist_to_mat(mnist_dir, output_file);
Hi everyone, I need help for transfering the data from a ThingSpeak' channel to Google Sheets. Please help me.
Suppose I want to use tiledlayout to draw a 4*6 figure. Now I want to let the first and second row of figures share the same ylabels, and so do the third and the fourth. But I did not find a way to do this. I tried to create two different tiledlayout on one figure, but tiledlayout did not allow me to do so. Thus, any suggestions?
Englisch Translate Französisch Deutsch Deutsch Russisch PONS Deepl übersetzer Spanisch Deutsch DeepL kostenlos Deutsch Englisch hallo, ich bitte um Hilfe! Seit Jahren habe ich Konto auf Thingspeak, den ich für meinen Zweck nicht richtig nutzen kann. Ich kann "Upoad to meine private Chanel", aber das lesen funktioniert nicht, weder in ArdunioIDE, noch Ardunio iot kann ich die gesendete Daten (Temperatur) von einem anderen Board lesen, es ist egal, ob ESP8266, ESP32, MKR, oder UnoWifi Rev2. Nichts! Die Beispiele im Bibliotek sind eine Katastrophe, "wetter-chanel" und diese funktionieren auch nicht. Auch nicht die von GitHub. Es sollte aber einfach sein, denn auf meiner Seite sehe ich ja "GET"+ url. inkl json+result.
Wo gibt es eine richtige sketch für "read private chanel/field" , welche funktioniert? Man braucht nicht die Wifi-Enstellungen, sondern den code für die Abfrage, "Serial.print"(value)"
Bitte um Hilfe, danke schön.
hello, I ask for help! I've had an account on Thingspeak for years, but I can't use it properly for my purpose. I can "Upoad to my private Chanel", but reading doesn't work, neither in ArdunioIDE nor Ardunio iot can I read the sent data (temperature) from another board, it doesn't matter whether ESP8266, ESP32, MKR, or UnoWifi Rev2. Nothing! The examples in the library are a disaster, "weather-chanel" and they don't work either. Not even the one from GitHub. But it should be easy, because on my site I see “GET”+ url. including json+result.
Where is there a proper sketch for "read private chanel/field" that works? You don't need the WiFi settings, but the code for the query, "Serial.print"(value)"
Please help, thank you very much.
Hello Everyone,
I'm running an IoT project at my university using a free . Basically, my system uploads the sensor data to 4 different fields of a ThingSpeak channel and I'm reading from or writing to the channel through Simulink. I have a few questions regarding this topic:
- I'm trying to upload to the server every 3 seconds (which seemed to be providing the best results so far). Since the channel only accepts data transmit every 15 seconds, what is the optimized upload interval rate to match the interval rate of the channel? Because otherwise I have realized that my interval rate can go up to 1min sometimes for some reason.
- Is reading from/writing to the channel through simulink while the system is uploading data to the channel slow down th whole process? What is your overall suggestion in this case?
I'm excited to hear your suggestions and experiences!
Regards,
Ege
I would like to propose the creation of MATLAB EduHub, a dedicated channel within the MathWorks community where educators, students, and professionals can share and access a wealth of educational material that utilizes MATLAB. This platform would act as a central repository for articles, teaching notes, and interactive learning modules that integrate MATLAB into the teaching and learning of various scientific fields.
Key Features:
1. Resource Sharing: Users will be able to upload and share their own educational materials, such as articles, tutorials, code snippets, and datasets.
2. Categorization and Search: Materials can be categorized for easy searching by subject area, difficulty level, and MATLAB version..
3. Community Engagement: Features for comments, ratings, and discussions to encourage community interaction.
4. Support for Educators: Special sections for educators to share teaching materials and track engagement.
Benefits:
- Enhanced Educational Experience: The platform will enrich the learning experience through access to quality materials.
- Collaboration and Networking: It will promote collaboration and networking within the MATLAB community.
- Accessibility of Resources: It will make educational materials available to a wider audience.
By establishing MATLAB EduHub, I propose a space where knowledge and experience can be freely shared, enhancing the educational process and the MATLAB community as a whole.
In one line of MATLAB code, compute how far you can see at the seashore. In otherwords, how far away is the horizon from your eyes? You can assume you know your height and the diameter or radius of the earth.
Keep calm and study PDEs
Product Models:LPS8N dragino
Firmware Version: lgw--build-v5.4.1704801796-20240109-2005
Hi all
at the moment i can not work with CODE dragino lora to gateway LPS8N and MQTT thingSpeak.
with root commands i can send DATA to thingspeak
mosquito_pub -d -h mqtt3.thingspeak.com -p 1883 -u PSoyJxYWBTQ9Hx8cExMZ... -I PSoyJxYWBTQ9Hx8cExM.... -P hCEd77jdiziYzUV6ygl.... -t channels/2466703/publish -m “field1=100&field2=100&status=MQTTPUBLISH”
so my question there anybody that can work with LPS8N dragino to MQTT ThingSpeak? which code arduino are using?
thanks in advance to answer.
Nelson
Me at the beginning of every meeting
A bit late. Compliments to Chris for sharing.
Hey MATLAB Community! 🌟
March has been bustling with activity on MATLAB Central, bringing forth a treasure trove of insights, innovations, and fun. Whether you're delving into the intricacies of spline conversions or seeking inspiration from Pi Day celebrations, there's something for everyone.
Here’s a roundup of the top posts from the past few weeks that you won't want to miss:
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Popular discussions
Celebrate Pi Day with cool MATLAB implementations and code. A delightful read filled with π-inspired creativity.
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Unlock the secrets of global climate data with MATLAB. This thread offers tools and insights for analyzing precipitation variability.
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These threads are just the tip of the iceberg. Each post is a gateway to new knowledge, ideas, and community connections. Dive in, explore, and don't forget to contribute your insights and questions. Together, we make MATLAB Central a vibrant hub of innovation and support.
Happy Coding!
sort(v)
8%
unique(v)
16%
union(v, [ ])
17%
intersect(v, v)
14%
setdiff(v, [ ])
12%
All return sorted output
33%
1193 votos
can you relate?
I am considering to use ThingSpeak for my use case which is electric motor drive where I want to do a predictive maintanace for.
Is it possible to use ThingSpeak to develop and evaluate the AI/ML model for such purpose and the deploy on realtime microcontroller?
Dear Sir,
Is Thingspeak support jason data format???
When I am sending data in plain text fiom MQTTX, I see it in dashboard but in JASON format it is not showing in dashboard.
Can you solve it?
This Arduino ino sketch utilizes the new Arduino R4 with LED matrix. I use a thermistor to measure temperature and send it to the led MAtrix for local display and also to ThingSpeak for cloud display at public
- Channel ID: 2300884
Note: I used Christopher's suggestion (elsewhere) to start with the Arduino R4 wifi example in the example folder of the Arduino IDE. That made all the difference in the world! Plus, I had serious issues with "write" data until I watched this YouTube video.
I have a development that requires 12 fields, but ThingSpeak only offers 8. Without further subscription, can I combine 2 Channels ?
