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Matt Kindig


Northwestern University Chicago

Active since 2011

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Answered
How to classify shapes of this image as square, rectangle, triangle and circle?
Another approach is to calculate the best-fit bounding rectangle of each object, such that the bounding rectangle can be oriente...

10 years ago | 6

| accepted

Question


Determine which function was used to generate hggroup?
Hello everyone, Is there a way to determine which function (e.g., quiver(), scatter(), contour(), etc.) was used to generate ...

10 years ago | 1 answer | 0

1

answer

Answered
How to average a column based on another column?
This is a good use of accumarray(): [ud,ix,iy]=unique( data(:,1)); output = [ud, accumarray(iy,data(:,2),[],@mean)...

10 years ago | 0

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Answered
How can I write a program to investigate whether a number belongs to matrix?
I think ismember() should do the trick: A=[1 2 3 5 21 2 4 0 11 3]; B = 11; C = ismember(B, A); %returns 1 B =...

10 years ago | 2

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Answered
Creating an array of datenum(s)
If I understand you correctly, this should do it: [~, time_index] = ismember( datenum(tv), second_tv);

10 years ago | 0

Answered
How to convert an image from rgb to lab by pixel by pixel matrix???
You can convert rgb to L*A*B colorspace using the makecform() and applycform() functions. From the documentation: cform...

10 years ago | 0

Answered
Is there a way to disconnect lines between data points while utilizing the plot function?
Another way is to insert a NaN between the dis-connected points, such as: x = [1;2;3;4;5;6;7;8;6]; y = [10;20;30;40;50;6...

10 years ago | 7

Answered
How to calculate the median for each day of the year in 91 years?
I think this is a good use of accumarray(). %some sample data, to illustrate approach Data = [1915 1 1 1000 1010; ...

10 years ago | 0

Answered
Finding minimum point from any function file input.
I would check out the documentation for fminsearch() and fminbnd(), or if you have the Optimization Toolbox, fminunc(): doc...

10 years ago | 0

Answered
How do I find values in a matrix which are closest to an integer which is the product of a given value?
I think I get what you are trying to do. I think the easiest way might be to use interpolation to fill in the missing values, as...

10 years ago | 1

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Answered
Read data from text file
You should be able to do it with textscan fid = fopen('/path/to/your/file.txt', 'rt'); output = textscan(fid, '%s %s %f ...

10 years ago | 3

Answered
and another "if" statement question
How long is the vector? Would this work? if all(A>3) %do something else %do other thing end

10 years ago | 1

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Answered
how to get some values from many text files and put them into the calculation ( please help)
One approach using regular expressions: %variables to average over AveVariables = {'Area', 'xbar', 'ybar', 'IXXw', 'IYY...

10 years ago | 0

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Answered
how to write program for following problem
I'm not going to given you the entire code, but to get you started, here's how you can do the parse: a = 'AD''BA''C'''; %...

10 years ago | 0

Answered
levenberg-marquardt in lsqcurvefit
Pass in an options structure: opts = optimset('Algorithm', 'levenberg-marquardt'); [parameters,resnorm,residual,exitflag...

10 years ago | 0

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Answered
Updating bounds in fmincon
You can implement the constraints on psi as a linear inequality constraint. If you check the documentation for your solver (e.g....

10 years ago | 1

Answered
How do I create variable names from string variables
If you can, avoid doing this. This explains why: <http://matlab.wikia.com/wiki/FAQ#How_can_I_create_variables_A1.2C_A2.2C....2CA...

10 years ago | 2

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Answered
Creating a matrix using a loop
[xx,yy]=ndgrid( -2:1:2, -2:1:2); xy = [xx(:), yy(:)]; x = xy(:,1); y = xy(:,2);

10 years ago | 1

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Answered
How to Multiply value in adjacent cell by cell above, Autofil formula in Matlab?
There is no generic "autofill" command. For the example you've given, the following logic would work: StartVar = 5; mult...

10 years ago | 1

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Answered
using multiselect uigetfile with dicomread
You probably need to pass in the full path to your DICOM file to dicomread(). Try this: for count = 1:numel(name) imag...

10 years ago | 1

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Answered
plotting normal vector in 3d
doc quiver3

10 years ago | 1

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Answered
Error using textread to read data containing "INF" or "NaN" with float data
Try using textscan() with the 'TreatAsEmpty' option: output = textscan([direct filename], '%22c %u %f %f %f %f %f %f %f %f ...

10 years ago | 2

Answered
How to read from a *.txt file to assign variables and paths
Easiest way is to parse with regular expressions and read into an output structure with named fields. %read in file str ...

10 years ago | 0

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Answered
Solving ODEs using matlab (ode45)
Did you forget the assignment sign? [T, XY] = ode45 ('diffxy', 0 10, [0 1 0])

10 years ago | 0

Answered
choose data points that nears each other and store in different matrix
One (non-loop) way: [x1,x2]=meshgrid(A(:,1)); [y1,y2]=meshgrid(A(:,2)); D = sqrt((x1-x2).^2+(y1-y2).^2); %distance m...

10 years ago | 0

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Answered
rotate 3D plane to a new 2d coordinate system
Simplest way is just using a transformation matrix. %assume points are Nx3, where N is number of points. %let first poin...

10 years ago | 1

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Answered
How can I extract the first non-zero in several specific segments of the same matrix?
ix1 = find(x(1:3,2),1,'first'); %index of first non-zero in x(1:3,2); x1 = x(ix1,1); %corresponding first-column value ...

10 years ago | 0

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Answered
Saving outputs to different folder than m-file.
%get the directory of your input files: pathname = fileparts('/input/file'); %use that when you save matfile = fullfi...

10 years ago | 3

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Answered
I need to remove every other 9 rows of a matrix
So, to confirm, you need to do the following: * remove rows 1-9 (9 rows) * retain rows 10-19 (10 rows) * remove rows 20...

11 years ago | 0

Answered
how to count the no of words in a sentence?
txt = fileread('hello.txt'); %read in file, assuming it is not too big sentences = strtrim(regexp(txt, '[\.\?\!]+', 'split...

11 years ago | 0

| accepted

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