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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Matlab genetic algorithm for instances selection problem with no convergence
This is my test using matlab ga function for instances selection or training set selection.
As you can see I used a simplified dataset to be sure of the performance.
You can see it in the first lines ...
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Error in SVM classifier RBF kernel in MATLAB?
I had written MATLAB function for RBF kernel in SVM classification but I am getting the following error:
Kernel function returns kernel product of incorrect size.
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Feature selection - How to identify the best subset
I am using three feature selection method on a dataset containing 15 inputs. I need to extract the best 5 features. Each of the three method gave a subset of the input dataset, but they are different. ...
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Method to Compare the Fit of of k-Medoids and GMM to my Dataset
I'm looking for a method(s) to compare the fit of k-Medoids and a GMM.
Currently, I'm looking at the distance between the max-min means of the GMM clusters and comparing that to the max-min medoid ...
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Matlab - Machine Learning: Hyperparameter tuning of a fitcecoc - model + training it on new data
I have trained a logistic regression multi-class model in Matlab for multi-class classification using XTrainSet_A / YTrainSet_A, look at this simplified code:
...
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23
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How do you implement the dual form of the soft-margin SVM in MATLAB using quadprog?
I'm having trouble trying to implement the primal and dual forms of the soft-margin SVM in MATLAB.
For a soft-margin SVM defined as $$\underset{\mathbf{w},b,\mathcal{E}_{i}}{min}\ \lambda||\mathbf{w}^...
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Time series prediction of individual customer (transaction count and gross value) using LSTM/NARX
Problem:
I'm trying to rewrite Matlab code that goal is prediction of gross value using historical data of 2 features: gross value of next week. The data is about customer transaction in retail where ...
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1
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56
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Detecting ellipses in an image
I’m trying to use CNNs to detect ellipses (of different shapes, sizes, orientation) in an image.
How do I do this?
I’ve tried using many centered ellipses as training (positive) examples and noise as ...
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131
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Perform DTW simultaneously on multiple trajectories
Good day,
I have ~50 sample trajectories (timeseries) showing reactor temperature over time for a given process.
In addition, I have a reference signal of the ideal trajectory for this process.
I ...
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Semi-Unsupervised learning - kmeans
Given data that contain n vector (m×1 each).
I want to cluster the data based on distance.
Also, each vector in the data is labeled to some category.
I used kmeans algorithm (in Matlab) to cluster the ...
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47
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Block matrix indexing
Hello this might be a stupid question but i need some help indexing a Matlab matrix consisting of several sub-matrices.
...
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154
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Why are my ridge regression coefficients completely different from ordinary linear regression coefficients in MATLAB?
I am attempting to implement my own Ridge Regression algorithm and I am trying to achieve similar coefficients found in a MATLAB tutorial on regression.
Specifically, on the MATLAB tutorial page you ...
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Which machine learning model is best for a combination of numerical and categorical data?
I want to develop a ML model which will allow my company to highlight employees which are at a risk of leaving the business, based on a variety of parameters such as performance, absence rates, ...
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Unable to train neural network for prediction
My data consists of a time series of values $\pm1$ and I am trying to apply a RBF NN as a function approximator. Essentially, the NN will take as input one data sample and predict the next sample (...
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Backpropagation on a CNN
I have tried searching for this, but it seems like no one addresses a key aspect of this problem (or maybe I'm overthinking this):
So, first let's assume we have a 3x3 image with a single channel, and ...
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Reducing features to 2 by PCA confusion Matlab
I am trying to reduce $500$ features to $2$ as an assignment. I wrote the following code and I am deeply concerned if it is true as when I plot it on the graph it does not look good. It should look ...
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279
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Performing 1D Depthwise conv using Keras 2D Depthwise conv
I would like to perform a 1D Depthwise convolution (ie the first step of the depthwise-separable convolution) for a machine learning model I am working on. This means that for an input activation ...
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Pixel labelled image is must for semantic segmentation using deep learning in matlab?
I have large set of CT images containing lung regions. But I don't have corrosponding pixel labelled images. So how I could do semantic segmentation using DL in matlab. Like a test program I created 6 ...
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23
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differences in NN optimization algorithm between Matlab and Scikit-Learn
I'm trying to build a neural network to estimate the responses of a nonlinear system. My database contains 1000 load cases (inputs) and maximum responses (outputs) from numeric simulations.
I'm using ...
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186
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Results of quadratic SVM in Matlab are different from the results obtained in Python
I am trying to replicate a quadratic SVM classifier from Matlab to Python, however I am having different results regarding the accuracy. In Matlab the accuracy is 0.8955 meanwhile in Python the ...
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47
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Looking for a machine learning algorithm that can classify line plots into two groups?
I have a dataset of many 2-D line plots that represent height versus position measured from an AFM.
I am interested in training a model by classifying these lines into two groups: presence of a defect ...
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How to calculate the different metrics for multi class classification
My confusion matrix has the following structure:
(Predicted)
C= ( actual) [TN FP
FN TP]
How can I calculate the Mathews ...
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130
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MNIST 2-layer NN failing to recognize certain digits
Recently I've been taking a look into some basic multilayer neural networks, and I decided to try tackling the MNIST database of handwritten digits using a 2 layer neural network with 100 neurons in ...
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1
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How to get used to matricial/vectorial operations?
I came to data science/machine learning from another background in computer science and i feel that i'm lacking of experience with matricial/vectorial operations.
Python or Matlab, for instance, ...
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111
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how to read emotion label of MSP-IMPROV dataset samples?
I need to read MSP-IMPROV dataset audio file's to conduct research. I read the help file that says 15th character of the file name, shows the emotion label of each utterance.
For example:
MSP-IMPROV-...
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721
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How to find the average over an area of center for a given radius
I have an excel file which contains the lat and long values of the center of a Tropical Cyclone(TC). The excel file is as given below:
...
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1
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29
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Optimization function returns the same optimal parameters for two labels
I've recently enrolled in the Coursera machine learning, and am working my way through making my own classifier for the Iris dataset problem using matlab. I'm training a classifier for each species (...
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131
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looking for a correlation function for categorical + numerical datasets in matlab
I am looking for a function in Matlab that calculates the correlation coefficient of a data set that includes categorical + numerical data. I am quite surprised this isn't as straightforward as I ...
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Matlab Optimization. Meaning of warning: "The slope should be 2. It appears to be 1."
I'm using the manopt package to solve some optimization problems in matlab. The problem is of the form.
problem.cost = @(x) f(x)
problem.egrad = @(x) g(x)
After the problem definition, I check ...
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Gradient descent diverges extremely
I have manually created a random data set around some mean value and I have tried to use gradient descent linear regression to predict this simple mean value.
I have done exactly like in the manual ...
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Optimization problem with different type of constraints
I'm new to optimization problems. I want to find optimum values for my objective function. You can imagine my function as E = f(t1, t2, t3). I want to minimize <...
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I want to use a neural network for a control block in MATLAB, but without Simulink
I have a physical model that produces an error value after running, which I want to minimize by a Neural Network. I can not find a MATLAB function however that lets me run the program and use the RMSE ...
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Why normalize function has a different result on a matrix vs single value?
I have a matrix like:
B=[ 1.5035; 1.5728; 1.6485; 1.5369; 1.5467; 1.572; 1.5374; 1.787; 1.5825; 1.6905];
Using normalize function like normalize(B,'range') ...
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Embedding git commit into the resulting data
Our pipeline works something like that:
Collect bunch of raw data (10-100 GB) from microscope
Process data using MATLAB scripts
Change few parameters based on raw data, as well as add new features to ...
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132
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kmean clustering
I am having a problem in Matlab. I would like to use kmeans clustering and then get the value and index of the centroid. For example, if there is an $5*5$ array, we do kmeans clustering where k=2 and ...
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Hyperparameter optimization performance comparison
I have used Bayesian optimization for hyperparameter tuning in a machine learning model. What is the best way to compare the performance of network with and without Bayesian optimization? I found some ...
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Using LSTM to forecast vehicle position - multivariate time series - Matlab
I am trying to train an LSTM model on Matlab to forecast the position of a vehicle when driving around a roundabout. My main concern right now is that my dataset consists of 4 features (X position, Y ...
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How to find the various matrix sizes in designing a CNN
I am trying to understand CNN especially the maths and working mechanism using Matlab as the coding language. I have few confusion regarding the concept and the associated programming and will be ...
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Tensorflow simple neural network has very bad performance in regression (curve fitting) problem
I'm trying to implement a very simple one layered MLP for a toy regression problem with one variable (dimension = 1) and one target (dimension = 1). It's a simple curve fitting problem with zero noise....
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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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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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134
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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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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 ...
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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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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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399
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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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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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66
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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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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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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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