https://sites.google.com/site/kolukulasivasrinivas/

Professional Interests: Mathematical Computing

Answered

Element subtraction of same matrix

A = [2,5; 3,8]; B = [2-2, 2-5, 2-3, 2-8; 5-2, 5-5, 5-3, 5-8; 3-2, 3-5, 3-3, 3-8; 8-2, 8-5, 8-3, 8-8]; A1 = A' ; ...

Element subtraction of same matrix

A = [2,5; 3,8]; B = [2-2, 2-5, 2-3, 2-8; 5-2, 5-5, 5-3, 5-8; 3-2, 3-5, 3-3, 3-8; 8-2, 8-5, 8-3, 8-8]; A1 = A' ; ...

2 hours ago | 1

Answered

Finding the maximum value in a specific row of a matrix

M = [3 6 1 -2; 3 0 -2 -4; 8 -3 5 4; -2 -3 -2 5]; [val1,idx1] = max(M(4,:)) % maximum in the row 4 [val2,idx2] = max(M(:,3))...

Finding the maximum value in a specific row of a matrix

M = [3 6 1 -2; 3 0 -2 -4; 8 -3 5 4; -2 -3 -2 5]; [val1,idx1] = max(M(4,:)) % maximum in the row 4 [val2,idx2] = max(M(:,3))...

2 hours ago | 0

Answered

how to animate two plots at the same time?

Put this line: comet3(xv,yv,zv) %xv yv zv are the values I get from solving the 2-body problem which I didn't include here int...

how to animate two plots at the same time?

Put this line: comet3(xv,yv,zv) %xv yv zv are the values I get from solving the 2-body problem which I didn't include here int...

3 hours ago | 0

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Answered

index exceeds the number of array elements (1).

This error occurs when you try to extract more number of elements than present in the array. EXample: A = rand(1,10) ; A(1) ...

index exceeds the number of array elements (1).

This error occurs when you try to extract more number of elements than present in the array. EXample: A = rand(1,10) ; A(1) ...

8 hours ago | 0

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Answered

Plot will not show lines

x = -0.923 : 0.01 : -0.633 ; f = 16*x.^3 - 13*x.^2 + 12*x + 15 ; g = -7*x.^3 - 6*x.^2 + 4*x - 6 ; plot(x,f, x,g) ylabel('...

Plot will not show lines

x = -0.923 : 0.01 : -0.633 ; f = 16*x.^3 - 13*x.^2 + 12*x + 15 ; g = -7*x.^3 - 6*x.^2 + 4*x - 6 ; plot(x,f, x,g) ylabel('...

9 hours ago | 0

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Answered

drawing a best fit graph

I = imread('image.png') ; I = rgb2gray(I) ; [y,x] = find(~I) ; % Get center idx = boundary(x,y) ; x = x(idx) ; y = y(id...

drawing a best fit graph

I = imread('image.png') ; I = rgb2gray(I) ; [y,x] = find(~I) ; % Get center idx = boundary(x,y) ; x = x(idx) ; y = y(id...

9 hours ago | 0

Answered

Find all values between 2 index columns

for i = 1:size(c,1) value = dataset(C(i,1):C(i,2)); end

Find all values between 2 index columns

for i = 1:size(c,1) value = dataset(C(i,1):C(i,2)); end

10 hours ago | 0

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Answered

I'm trying to create three curves, but my plot is blank

Code looks meaning less though. mi = [2814 1000 19781]; c(1) = 2080; c(2) = 1580; c(3) = 2580; v = c*log(19781/2814); figu...

I'm trying to create three curves, but my plot is blank

Code looks meaning less though. mi = [2814 1000 19781]; c(1) = 2080; c(2) = 1580; c(3) = 2580; v = c*log(19781/2814); figu...

10 hours ago | 0

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Answered

How to find the point of intersection of two level curves?

The best function for you: https://www.mathworks.com/matlabcentral/fileexchange/22441-curve-intersections

How to find the point of intersection of two level curves?

The best function for you: https://www.mathworks.com/matlabcentral/fileexchange/22441-curve-intersections

23 hours ago | 0

Answered

How to plot in command window

If your data is 2D, use plot plot(x0,yo) If your data is 3D use plot3. plot3(xo,yo,r) ; Note that to use plot command x0,y0...

How to plot in command window

If your data is 2D, use plot plot(x0,yo) If your data is 3D use plot3. plot3(xo,yo,r) ; Note that to use plot command x0,y0...

23 hours ago | 0

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Answered

For loop gives error: Unable to perform assignment because the indices on the left side are not compatible with the size of the right side.

This error occurs, when you try to save more number of elements than you initialized. Example: A = rand(10,5) ; % initialize ...

For loop gives error: Unable to perform assignment because the indices on the left side are not compatible with the size of the right side.

This error occurs, when you try to save more number of elements than you initialized. Example: A = rand(10,5) ; % initialize ...

23 hours ago | 0

Answered

Delete all values except the max value

A = [3,10,8 4,8,1] ; [val,id] = max(A,[],2) ; idx = A<val ; A(idx) = 0 ; A

Delete all values except the max value

A = [3,10,8 4,8,1] ; [val,id] = max(A,[],2) ; idx = A<val ; A(idx) = 0 ; A

1 day ago | 0

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Answered

how to get plot with the points increasing with changing color (as points increase their color change from grey to black)

X = repmat((1:5)',1,5) ; Y = rand(5,5) ; plot(X,Y,'.-')

how to get plot with the points increasing with changing color (as points increase their color change from grey to black)

X = repmat((1:5)',1,5) ; Y = rand(5,5) ; plot(X,Y,'.-')

1 day ago | 0

Answered

I need to fill a column data with a specific value

Let data be your m*2 data. x = data(:,1) ; y = data(:,2) ; y0 = y ; % idx = A your indices which should be nan y(idx) ...

I need to fill a column data with a specific value

Let data be your m*2 data. x = data(:,1) ; y = data(:,2) ; y0 = y ; % idx = A your indices which should be nan y(idx) ...

1 day ago | 0

Answered

Features Classification using deep leaning.

Refer: https://in.mathworks.com/help/deeplearning/ug/create-simple-deep-learning-network-for-classification.html

Features Classification using deep leaning.

Refer: https://in.mathworks.com/help/deeplearning/ug/create-simple-deep-learning-network-for-classification.html

1 day ago | 0

Answered

Select a random element of a vector and use randi command

A = magic(5) ; A = A(:) ; N = numel(A) ; idx = randi(N,1) ; A(idx) = rand

Select a random element of a vector and use randi command

A = magic(5) ; A = A(:) ; N = numel(A) ; idx = randi(N,1) ; A(idx) = rand

1 day ago | 0

Answered

How to define these two functions?

syms t alpha f = t^(alpha-1)*exp(-t) ; F = int(f,t,[0 inf])

How to define these two functions?

syms t alpha f = t^(alpha-1)*exp(-t) ; F = int(f,t,[0 inf])

1 day ago | 0

Answered

Need Help for fprintf

% data = importdata(filename) ; data = [1 10 100 1000 10000 2 20 200 2000 20000 3 30 300 3000 30000] ; ...

Need Help for fprintf

% data = importdata(filename) ; data = [1 10 100 1000 10000 2 20 200 2000 20000 3 30 300 3000 30000] ; ...

2 days ago | 1

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Answered

showing hours elapsed not date and time data

Let d be your datetime array. d.Format = 'hh:mm:ss'; t = cellstr(d)

showing hours elapsed not date and time data

Let d be your datetime array. d.Format = 'hh:mm:ss'; t = cellstr(d)

4 days ago | 0

Answered

How do I remove all filenames from my cellarray with .m ending, if else how do I save those with .bmp?

idx = contains(filenames,'.bmp') ; filenames(idx)

How do I remove all filenames from my cellarray with .m ending, if else how do I save those with .bmp?

idx = contains(filenames,'.bmp') ; filenames(idx)

4 days ago | 0

Answered

Horizontal line in plot up to a graph

If you have the xlimits (x0,x1) and the y-value..the required equations is y = k. x = 1:10 ; k = 3 ; y = k*ones(*Size(x)) ; ...

Horizontal line in plot up to a graph

If you have the xlimits (x0,x1) and the y-value..the required equations is y = k. x = 1:10 ; k = 3 ; y = k*ones(*Size(x)) ; ...

4 days ago | 0

Answered

Summing randomly generated numbers

n1 = 0:0.1:0.9; n2 = 0:0.1:0.9; r1 = n1(randi([1,numel(n1)])); r2 = n2(randi([1,numel(n2)])); thesum = r1+r2

Summing randomly generated numbers

n1 = 0:0.1:0.9; n2 = 0:0.1:0.9; r1 = n1(randi([1,numel(n1)])); r2 = n2(randi([1,numel(n2)])); thesum = r1+r2

4 days ago | 0

Answered

Array indices must be positive integers or logical values.

function [z]=phi(x) %Determine phi(x) using the formulas provided %2/25/21 %AE 227 a=0.4361836; b=0.1201676; c=0.937298;...

Array indices must be positive integers or logical values.

function [z]=phi(x) %Determine phi(x) using the formulas provided %2/25/21 %AE 227 a=0.4361836; b=0.1201676; c=0.937298;...

4 days ago | 1

Answered

How can I surface plot a 1000x2 matrix?

A = randn(1000,2); hist(A(:)) hist(A)

How can I surface plot a 1000x2 matrix?

A = randn(1000,2); hist(A(:)) hist(A)

4 days ago | 0

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Answered

How to find the position of a number in an cell-array?

P= {[2,5], [3], [], [1,14], [], [9]} ; N = length(P) ; val = 14 ; for i = 1:N idx = ismember(14,P{i}) ; if any(i...

How to find the position of a number in an cell-array?

P= {[2,5], [3], [], [1,14], [], [9]} ; N = length(P) ; val = 14 ; for i = 1:N idx = ismember(14,P{i}) ; if any(i...

4 days ago | 0

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Answered

count number of rows in csv outside of matlab

csvFiles = dir('*.csv') ; N = length(csvFiles) ; f = cell(N,1) ; % first row l = cell(N,1) ; % last row for i = 1:N ...

count number of rows in csv outside of matlab

csvFiles = dir('*.csv') ; N = length(csvFiles) ; f = cell(N,1) ; % first row l = cell(N,1) ; % last row for i = 1:N ...

4 days ago | 0

Answered

Creating a 3D graph of many 2D-view surface plots

On using contour, you will get the points/ locations (x,y).... do interp2 and you will get the respective z values......do the s...

Creating a 3D graph of many 2D-view surface plots

On using contour, you will get the points/ locations (x,y).... do interp2 and you will get the respective z values......do the s...

4 days ago | 0

Answered

How to create a netcdf in matlab which can be read by grads without using descriptor file?

% nc filename to be written file = 'myfile.nc' ; %% Write lon and lat variables % Get data lon = 1:10 ; lat = 1:10 ; nx ...

How to create a netcdf in matlab which can be read by grads without using descriptor file?

% nc filename to be written file = 'myfile.nc' ; %% Write lon and lat variables % Get data lon = 1:10 ; lat = 1:10 ; nx ...

4 days ago | 0

Answered

Finding matching points between two 2d point sets, but different sizes

Read about knnsearch.

Finding matching points between two 2d point sets, but different sizes

Read about knnsearch.

4 days ago | 0

Answered

Eigen Vectors and Values using Matlab

A=[4 6 2;6 0 3;2 3 -1]; lambda=eig(A) syms l eqn = det(A-l*eye(3))==0 ; solve(eqn,l) ; l = double(vpasolve(eqn,l))

Eigen Vectors and Values using Matlab

A=[4 6 2;6 0 3;2 3 -1]; lambda=eig(A) syms l eqn = det(A-l*eye(3))==0 ; solve(eqn,l) ; l = double(vpasolve(eqn,l))

5 days ago | 0