Question

How to display multiple images (non indexed images) with different sizes in a row?

Hi Say I have 3 images and they are not indexed images therefore they don't have X, map, they only have RGB values. And th...

10 months ago | 2 answers | 0

Question

imshow using double or uint8 RGB values - confusing

Hi, I'm a bit confused about 'imshow' My guessing is that imshow can be used with 2 types of RGB data. RGB values are b...

10 months ago | 1 answer | 0

Question

How to draw a L*a*b* colour space or HSV colour space (2D)?

Hi I would like to draw the LAB or HSV colour space in 2D (see below) but I don't know how to draw it. I found some code onl...

12 months ago | 3 answers | 0

Question

How to understand C in pcolor? Why are specific colours not other colours coming out of certain numbers?

Hi, I'm struggling to understand C in pcolor. From the official website, https://uk.mathworks.com/help/matlab/ref/pcolor...

12 months ago | 1 answer | 0

Question

How to make the white background whiter and black prints blacker and remove the highlight color (green) in an image?

12 months ago | 0 answers | 0

Question

Does PCA apply on the raw data or the data needs to be pre-normalized before applying pca function?

Hi, According to the link below, https://uk.mathworks.com/help/stats/pca.html coeff = pca(X) I'm wondering whether this ...

1 year ago | 0 answers | 0

Question

Should I use PCA to order the data points in order to find the mode of the data points?

Question 1: I roughly know that PCA is used for reducing dimensions, it is used for reducing the dimension of features not the d...

1 year ago | 1 answer | 0

Question

How to sort the files in a folder by date?

Hi, For example, I have 3 image files in a folder, looks like below (Fig 1). I then tried to get the information of th...

1 year ago | 1 answer | 0

Question

Faster way of replacing multiple rows with same vector without using a loop?

Hi, I have a matrix a (see below). I would like to replace the 1st and 3rd row with the same row vector [255 100 0]. a = ...

1 year ago | 3 answers | 0

Question

Fast way to replace elements in a matrix?

Hi, for eample I have an a matrix a = 245 255 255 254 252 255 251 250 239 rules: find the row i...

1 year ago | 1 answer | 0

Question

Why it is 94? corss-validation for regression tree problem.

Hi, Example shown on the page below. https://uk.mathworks.com/help/stats/regressiontree.crossval.html load carsmall X = [A...

1 year ago | 0 answers | 0

Question

cvloss or kfoldloss for regression tree?

Hi, I'm a bit confused with 'cvloss' and 'kfoldLoss'. kfoldLoss https://uk.mathworks.com/help/stats/regressio...

1 year ago | 0 answers | 0

Question

'MinParentSize' and 'MinLeafSize' -- regression tree

https://uk.mathworks.com/help/stats/fitrtree.html It introduces the MinParentSize below as: Minimum number of branch node ob...

1 year ago | 0 answers | 0

Question

Min objective and function evaluations

As I was learning to optimize regression tree, I'm struggling to understand some of the codes and graphs generated in the matlab...

1 year ago | 1 answer | 0

Answered

@(x)sum(x.IsBranch)

Anonymous Functions You can create handles to anonymous functions. An anonymous function is a one-line expression-based MATLAB ...

@(x)sum(x.IsBranch)

Anonymous Functions You can create handles to anonymous functions. An anonymous function is a one-line expression-based MATLAB ...

1 year ago | 0

Question

@(x)sum(x.IsBranch)

Hi, https://uk.mathworks.com/help/stats/fitrtree.html As I tried to understand the example line by line, I am stuck at bel...

1 year ago | 2 answers | 0

Question

What is 'categorical predictor' in decision tree for regression

Hi, I'd like to use Matlab's own example for the question. Please refer to https://uk.mathworks.com/help/stats/fitrtree.html for...

1 year ago | 1 answer | 0

Question

Entropy to calculate information gain for decision tree for classification problems.

Hi I wonder whether Matlab has the function to calculate the entropy in order to calcuate the information gain for decision ...

1 year ago | 0 answers | 0

Question

How to construct a regression tree

Hi, As I was trying to understand the matlab example on the documentation page for constructing a regression tree https://uk.ma...

1 year ago | 0 answers | 0

Answered

Hierarchical Clustering - linkage(y)

Only just figured it out. The first and second columns are the new group number after clustering. 4 elements in x each wa...

Hierarchical Clustering - linkage(y)

Only just figured it out. The first and second columns are the new group number after clustering. 4 elements in x each wa...

1 year ago | 0

| accepted

Question

Hierarchical Clustering - linkage(y)

Hi, I don't fully understand the linkage function and its outputs. >> x=[1 2 6 8]'; >> y=pdist(x) y = 1 5 ...

1 year ago | 1 answer | 0

Question

Finding the adjoint of a Matrix

Hi I'm trying to find the adjoint of a matrix. On MathWorks documentation webpage, the instruction look something like below...

1 year ago | 2 answers | 0

Question

How to divide a cell into two groups based on two types of strings

Hi, I have a cell, say 20 by 1, which looks like below (ignore the 879). Each one in a cell is a string such as 'bad1.png'. ...

1 year ago | 1 answer | 0

Question

Try to display a different image on an axes everytime I click on the axes

Hi bros and sis, ------------------------------------------------------------- Say I have three images named '1.jpg', '2.j...

2 years ago | 2 answers | 0

Question

Matlab documentation webpage is not working properly

None of the 'Try it in Matlab' buttons on the webpage below is working correctly. I desparately need the sample code to try it i...

2 years ago | 1 answer | 0

Question

Passing data between two GUIs

Hi, I made two GUIs, namely 'G1' and 'G2'. For example, if I have a variable 'handles.index = 2' in G1, how can I read thi...

2 years ago | 1 answer | 0

Question

show an image in an AXES a) without outlines and b) can be clicked using ButtonDownFcn

Hi, I would like to show an image in the axes in the GUI to achieve two things: a) the image showed has no outlines if I use th...

2 years ago | 0 answers | 0

Answered

Problem with BottonDownFcn for a Pushbutton

Just found the answer myself. 'ButtonDownFcn' is not suitable for 'pushbutton', rather I should use 'CallBack' instead. So...

Problem with BottonDownFcn for a Pushbutton

Just found the answer myself. 'ButtonDownFcn' is not suitable for 'pushbutton', rather I should use 'CallBack' instead. So...

2 years ago | 0

| accepted

Question

Problem with BottonDownFcn for a Pushbutton

Hi I created a simple GUI like showing below. What I would like to achieve is that when I click on the 'Start' button,...

2 years ago | 1 answer | 0

Question

3D mesh plot with colour

Hi I have some L*, a*, b* data. Sample data look like something below. <</matlabcentral/answers/uploaded_files/108397/lab...

2 years ago | 0 answers | 0