Questions tagged [matlab]
MATLAB is a high-level language and interactive programming environment for numerical computation and visualization developed by MathWorks. Don’t use both the [matlab] and [octave] tags, unless the question is explicitly about the similarities or differences between the two. When using this tag, please mention the MATLAB release you're working with (e.g. R2017a).
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Is it possible to change test and train data size when using crossvalind function with Kfold param?
I was looking at MATLAB Help and want to work with "crossvalind" function.
It would two parameters that you can use it.
If you use "HoldOut" you can define partition size of test and train data set ...
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9 views
How to generate synthetic data for a prediction task in Matlab
I want to generate synthetic data for predicting the grade of the ball bearing which is a continuous number in the range of 2 to 10. This is assigned randomly or if somebody can propose a logical way ...
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4 views
How to calculate performance and change train and test data size in MATLAB NNC Toolbox?
I used MATLAB Application toolbox for clustering but I don't know how to :
Calculate performance and Error rate
How to change test and train data size
Script:
...
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1answer
29 views
Is there a common strategy to measure if a difference-significance of two areas under two ROC curves
I conduct sound detection experiments with mice.
I have a stimulus sound and a "noise" sound that shoukd be ignored.
I want to measure how well the mouse ignors the noise (with respect to, say, ...
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15 views
Why does gradient descent fail training a network for predicting times table?
Cross posted
I am training a feedforwardnet with gradient descent traingd as backpropagation algorithm to predict times table.
...
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13 views
Is kFoldLoss simply the average classification error?
I'm using a kNN classifier in MATLAB to classify ECG signals, with 5 fold cross validation I get almost 97% accuracy. However, I'm not entirely sure if this is truly the accuracy value. By default the ...
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1answer
21 views
Why GA convergence curves continue as two parallel lines?
I'm working on a optimization problem and using GA algorithm (in MATLAB, ga function).
As you know MATLAB plots GA result with two curves, one for the best values and other to show the mean values ...
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1answer
27 views
What method is recommended after outliers removal?
I have a data of mice reaction times. In every session, there are some trials in which the mouse "decides of a break" and responds after a long time to these specific trials.
I was thinking of ...
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13 views
Octave or python for implementing Machine Learning [closed]
When is the need to learn octave or Mat Lab for Machine Learning? Are these required if you are proficient in python?
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13 views
How to generate synthetic datasets using randi and rand?
I have real datasets of 3 years. Now, I want to generate more datasets based on the behavior of these datasets to test my algorithm. Is there any way to generate synthetic dataset using ...
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25 views
Why do the training curve fall sharp suddenly?
I am training a CNN classifier on a binary balanced dataset. The dataset has 4500 numbers of tweet data along with the class of the tweet. During training, I am applying, GLOVE embedding of 300 ...
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1answer
51 views
Why is my Python Altair chart printing a blank line?
Wondering if anyone can help me understand why python altair chart is not printing...
I’m only seeing this when I run the code:
It literally isn’t outputting anything.
This is what my chart looks ...
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20 views
Local Interpretable Model-Agnostic Explanations (LIME) implementation on MATLAB
Do you know if there's a MATLAB implementation of the LIME framework, by Marco Ribeiro et al.? Specifically, i'm referring to this work LIME by Marco Ribeiro et al.
I have seen the author have a ...
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38 views
Why FP-Growth is slower than Apriori?
My project is about Data mining (in MATLAB) and want to use Apriori and FP-GRowth to extract rules (Associate Rule Mining).
I read in somewhere on the internet, FP-Growth should be faster than Apriori ...
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1answer
34 views
Feature selection method explanation
In the context of feature relevance, I am trying to understand the meaning of the correlation method for feature selection. Can somebody please explain if the following results of the correlation ...
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17 views
How to generate artificial datasets in MATLAB based on behavior of real datasets?
To understand: Let's consider a scenario. I have real datasets of 2 buildings showing different behaviors of occupants. Now to expand the analysis for multiple buildings, I want to generate simulated ...
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13 views
How to handle variables with text and number?
This is a post with two related questions in one.
The first question is:
What is the correct procedure when I have variables with different kind of information? Imagine you have a column which has ...
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34 views
How to Compute Logistic Regression Cost Function?
I'm using MATLAB to calculate the Logistic Regression Cost Function, and I don't get the expected output when I test my code. My steps all seem to be logically correct. Can anyone please help me fix ...
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17 views
How can solve data imbalance issue in MATLAB for a PatternNet?
I have built a Pattern recognition NN in MATLAB. I have two datasets, one for training and one for testing each of 4500 samples.
The number of classes is 3. Out of the 3 classes, class #1 has approx ...
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1answer
28 views
Modelling in python and scoring in MATLAB?
I have model objects either pickled object or H2O POJO. Is it possible to call those objects and do the scoring in MATLAB?
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40 views
How to implement loss function for CNN-SVM implementation
I am using Matlab R2018b and am trying to infuse svm classifier within CNN. My plan is to use CNN only as a feature extractor and use SVM as the classifier. I know people have already implemented it a ...
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1answer
232 views
What should I master better for professional data science in economics and finance? [closed]
First, excuse me for the noob and long question which is probably doesn’t even belong to here, I know there are several question been answered like this out there, but I think this is going to be up-...
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1answer
28 views
How to store a trained Random Forest model in python or matlab as a matrix
Is it possible to store a random forest model in python (or matlab). Then use that trained model in a C program?
I am trying to do this because I am making a myoelectric prosthetic, and you can only ...
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13 views
how to read all my audio file from one directory and store the outputs for all the files in one variable (matrix)
I would like to run the program over all the samples of audio file and store the output in a single variable. For example, if my folder is "audio" inside that I have 10 audio files (...
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2answers
39 views
Finding roots of a non linear expression when multiplied with a linear expression
Here is a simple polynomial equation:
b^2 + 2b + 1 = 0
I could easily solve this as:
...
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1answer
14 views
Estimating the value of b in a polynomial expression
How could I estimate the value of b in the given polynomial equation:
...
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27 views
Implementation of Layer-wise relevant propagation in MATLAB from scratch
I'm having serious issues with the implementation of the LRP algorithm for neural networks in MATLAB. The challenge is to implement the equations correctly. I'm trying to implement the deep-Taylor $\...
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8 views
Error using imread function in matlab code
I was doing some sort of speech recognition pattern for recognition of sound but I stuck at imread error in matlab, any advice what to change in picture below you can find code and error.
Code
Error
...
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20 views
How to develop this type of neural network? [closed]
I was given this task to develop, this type of neural network but I never done speech recognition and that type of recognition in Matlab, so could anyone please help and give some help about this task....
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2answers
96 views
Shouldn't an autoencoder with #(neurons in hidden layer) = #(neurons in input layer) be “perfect”?
I'm exploring autoencoders for the first time. I'm using the Matlab neural networks toolbox. I have created a synthetic dataset consisting of points in 2D space plus some noise. My idea was to ...
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0answers
36 views
Implementing the simplest CNN, how to choose the first conv layer?
I'm working on a College assignment and I choose to implement an image classifier with Convolutional Neural Network using Matlab, I based this idea on this tutorials: How Convolutional Neural Network ...
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0answers
28 views
UnderBagging Testing in Matlab
I used UnderBagging for an imbalanced dataset with 45700 observation with 20 fetures. 45000 observations are 1 and 700 are 0.
I used UnderBagging for classifier C ( for example for Decision Tree). I ...
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1answer
18 views
What's the correct form of use the real coded genetic algorithm?
i'm new with the ga and i can't found specific info about the real coded ga, i want to do an antennas array optimization by using the real values of antennas position , phase and amplitude, but in my ...
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1answer
44 views
How to find which features have been selected by PCA algorithm?
I used PCA function in MATLAB to decrease features on my data set.
By this code I can reduce features from 12 to 8(as an example). It works good but my question is that how can I found with feature ...
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1answer
30 views
Does PCA decrease the feature on my Data set or just decrease the dimension?
I'm new in AI and sorry if my question is simple. I have a data set and want to use PCA to decrease the feature but after some research on the internet I'm confused about decreasing dimensions and ...
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2answers
35 views
Linear regression incorrect prediction using Matlab
In the plot below the red crossed line is the actual curve and the crossed blue line is the predicted curve. I am using least squares for linear prediction. I have used 1:79 examples in training and ...
4
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1answer
276 views
Training a classifier when some of the features are unknown
I am training a classifier in Matlab with a dataset that I created.
Unfortunately some of the features in the dataset were not recorded.
I currently have the unknown features set as -99999.
So, for ...
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3answers
83 views
Why are pandas/R/etc so common in a data scientist or analyst's workflow when one can resort to UDFs in an RDBMS?
It seems common for an analyst to have this workflow when using an RDBMS: use SQL to get a subset of data from the database, export it or use a connector, and then apply a data mining / model ...
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1answer
338 views
Advice on transitioning from Andrew Ng's Stanford Coursera Machine Learning (in MATLAB) into Python?
I'm currently finishing up Andrew Ng's Coursera course, taught in MATLAB/Octave, but I'm looking to code in Python. The course is an introduction into how some algorithms work from scratch. These ...
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1answer
83 views
Tuning C hyper parameter in Soft Margin SVM in Matlab
How to tune the C 'BoxConstraint' hyperparameter in soft margin SVM to get the best optimal value?
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2answers
45 views
Where can I find an algorithm for human activity classification using thigh and shank sensors?
I am working on a project where I initially need to classify the type of activity a subject is performing based on raw accelerometer and gyroscope data from the thigh and shank of both legs. The type ...
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45 views
Hard margin SVM in Matlab
How can I build a hard margin svm model using matlab builtin functions such as fitcsvm and fitclinear? Should I set the ...
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0answers
146 views
SVM hard and soft margins in matlab,
I am comparing the performances of several SVM models in matlab using the fitcsvm function,
and I want to double check that I am using the correct syntax
for hard ...
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0answers
146 views
SVM hyperparameters using Matlab's fitcsvm and OptimizeHyperparameters
I am building SVM models and will compare their performances, linear vs RBF,
and I'm using OptimizeHyperparameters to get best hyperparameters C (BoxConstraints)
...
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0answers
21 views
DNN practice: errors and strange behavior
I've built a neural net for regression, with stochastic updates, for practice (shared below). It's having trouble modeling test data if more than one hidden layer is used.
The test outputs are a ...
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0answers
232 views
Local Binary Patterns features using matlab 'extractLBPFeatures'
I am trying to understand the extractLBPFeatures function to extract the 59 uniform features, here is a simple code that extracts the 59 features from an image
<...
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0answers
18 views
Local Binary features with unit16 images vs unit8 images
I have unit16 image dataset, and I would like to extract LBP features from it using the Matlab function extractLBPFeatures, which uses uniform LBP (59 features).
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2answers
258 views
Setting best SVM hyper parameters
I have a non linear data set, and I am using SVM (RBF kernel) to build a classification model, but not sure how to set the best hyperparameters of the SVM, C and gamma in Matlab ...
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20 views
Local Binary Patterns features
I have a dataset of images that differ in sizes, and when I extract the local binary pattern (uniform local binary 59 feature) from them I get several features as zeros, is it acceptable as features, ...
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184 views
Plotting ROC curve in cross validation using Matlab perfcurve
I have the following code for a binary classifying using SVM, and 10 cross-validation,
...
