Generate specific shape randomly using MATLAB

Hello every one, I hope you are doing well

i have the following code,in which i have two thing. first is the val in which i have the value like 200 is the value and it repeat 120 times to complete the shape.

I want to do it randomly , like the value generate randomly between 1 to 1000 and num is also randomly between 1 to 500 . How can i generate it in MATLAB

val = [200,500,800,1000,800,900,700,300,600,150];
num = [120,400,200,400,300,450,200,400,500,400];
out4 = repelem(val,num);
scatter(1:length(out4),out4)

[David Hill]

Your explaination is not clear to me. A short example would be helpful.

Answer 1

[Image Analyst]

To generate fractional random numbers use rand(). To generate random integers use randi().

randomDoubles = 999 * rand(1, length(val)) + 1; % Between 1 and 1000
randomIntegers = randi([1, 500], 1, length(num)); % Between 1 and 500

Not sure what else you need to know beyond that. If you need something else, be very explicit and specific.

[Med Future]

Like the picture below . i want to generate this shape with random values .

Like i have the value 200,500 300.. first i generate a array of this random value .

then repeat the value with another random value like 200 repeat 120 times

[Med Future]

@David Hill @Image Analyst I have explain the problem above . I want to generate that kind of shape randomly . now i am manually doing it using above code.

Answer 2

[Image Analyst]

Try this:

val = unique(sort(20 * randi(50, 10, 1)))
for k = 1 : length(val)
    y = val(k);
    num1 = randi(3500);
    num2 = randi(4000);
    plot([num1, num2], [y, y], 'b.-', 'LineWidth', 5, 'markerSize', 20)
    hold on;
end
grid on

[Med Future]

@Image Analyst why you just ploting that? i want to be it in a numeric array

[Med Future]

@Image Analyst i want to generate the a large dataset. which is randomly like the above shape

[Image Analyst]

I plotted that because that's what you said you wanted: "Like the picture below . i want to generate this shape with random values ."

How many elements do you want there to be between the left endpoint of the line segment and the right endpoint? You can use

numVec = linspace(num1, num2, numberOfElements);

A good investment of your time:

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[Med Future]

@Image Analyst i want it to in array. plotting is just an option.

like the code you share below how can i save this results in Array to generate a dataset like above random shapes

val = unique(sort(20 * randi(50, 10, 1)))
for k = 1 : length(val)
    y = val(k);
    num1 = randi(3500);
    num2 = randi(4000);

[Med Future]

@Image Analyst Have you get the idea what i want to do ?

[Image Analyst]

Again, "How many elements do you want there to be between the left endpoint of the line segment and the right endpoint?"

And do you want each value of val to be in its own row? Or maybe you want this:

val = unique(sort(20 * randi(50, 10, 1)))
m = zeros(length(val), 4000)
for k = 1 : length(val)
    y = val(k);
    num1 = randi(3500);
    num2 = randi(4000);
    index1 = min([num1, num2]);
    index2 = max([num1, num2]);
    plot([num1, num2], [y, y], 'b.-', 'LineWidth', 5, 'markerSize', 20)
    hold on;
    m(k, index1 : index2) = 1;
end
grid on

[Med Future]

@Image Analyst let me explain.

I want the data that each row contain 1x1000 shape like 1000 samples in each row

i want 200 rows like that data in which shapes are randomnly generated and saved in a array .

Like the above code i have share in which a single row have shaped of 1x3370.

I want it to be randomnly generate

[Image Analyst]

Try this:

val = sort(randi(1000, 200, 1));
m = zeros(length(val), 1000);
for k = 1 : length(val)
    y = val(k);
    num1 = randi(3500);
    num2 = randi(4000);
    index1 = min([num1, num2]);
    index2 = max([num1, num2]);
    plot([num1, num2], [y, y], 'b.-', 'LineWidth', 3, 'markerSize', 20)
    hold on;
	indexes = round([index1, index2] / 4) % Now go from 1-1000 instead of 1-4000
    m(k, indexes) = y; % m is a 200 by 1000 array
end
grid on

Now you have a 200 row array where the value of the y height goes from index1 to index2. There are 1000 columns which indicate x going up to 4000.

[Med Future]

@Image Analyst Sir thats wrong my whole array is zero .just one value is some nonzero digit.

Have you run my own code.

I will explain my code so you get idea

i have one value for example 200 which is repeated for some samples like 120 time.

after next value 500 which is repated 500 times,

I want this to be in random form.

Like i randomly picked first value for example 10. then it repeated random time between 500. and so on to make a full aray

[Image Analyst]

Sorry, I tried, but now I'm heading out now to do some errands. Once you take that 2 hour training you'll be able to do it yourself. It sounds like it's a simple application of calling rand() or randi() and then using a for loop, something you'll be able to do after taking the 2 hour training. Good luck.