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# William

Last seen: Today Active since 2012

Semi-retired physicist with interests in numerical modeling and mathematics.

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Bitshift cannot work on negative numbers
I believe this is happening for the following reason: The documentation states that "If A is a double array, and ASSUMEDTYPE is...

How to calculate the conditional probability of an event?
Actually, I believe that p(C|A) would be: y = strfind(array, 'A'); N_A = length(y); p_CA = N_AC/N_A; There is one further th...

How to calculate the conditional probability of an event?
Myriam, If A, B and C were variables with the values 1, 2 and 3, then in your example: array = [1, 1, 2, 1, 3, 1, 2, 2, 2, 3, ...

How to calculate the conditional probability of an event?
Hello Myriam. It is not clear whether A, B, and C here are text characters, or if they have numeric values. If we assume they...

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trigonometric non linear equation
I have no idea what this question is about, but I do notice that some of the expressions are surrounded with curly braces { } ra...

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How to 3D plot a circle with radius of 1 in x y and sine wave in z?
How about this: theta = linspace(0,2*pi,100); x = sin(theta); y = cos(theta); z = sin(2*theta); figure(); plot3(x,y,z);

Plotting a row in a Matrix
That would be: plot(sortpopulation(1:10,5));

Adding each values to row vector
... but if you just want to create a vector with three values, you would use a statement like: a = [1,2,3]; This produces a ve...

How do I plot a function over a specific range of x values?
Erica, I think fplot() will work if it is called correctly. If you want to use it, you need to define the function so that it ...

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For loop execution.
I think it may be the 4 clauses that read like (t >= 0.1 & t <= 2.5). Shouldn't these say (t(d) >= 0.1 & t(d) <= 2.5)?

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what function to use to find frequency of values in set?
... or maybe histcounts(R12) to get a histogram.

Why do i get the error "Dimensions of arrays being concatenated are not consistent"
The problem in the second program is the statement 'theta(i) = theta', which is changing theta from a scalar into a vector. The...

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Animate creation of a circle clockwise and anticlokwise for different staringpoints
Tim, A correction to the last message. If you want to go counterclockwise, you need to make the final angle bigger than the st...

Animate creation of a circle clockwise and anticlokwise for different staringpoints
Hi Tim, Actually I have been thinking a little more about this, and I believe it is even easier than I suggested. You don't ne...

Animate creation of a circle clockwise and anticlokwise for different staringpoints
Hi Tim, I don't think there is any problem with the cases you describe. The values of sin() and cos() are periodic in their ar...

Animate creation of a circle clockwise and anticlokwise for different staringpoints
Tim, I think you could avoid all the special cases by making use of the atan2() function. This function is defined for points ...

How to use for loop structure to calculate two vectors to dot product
a = 1:5; b = 6:10; c = 0; for j = 1:5 c = c + a(j)*b(j); end However, this calculation can be done more simply with t...

Subtraction of elements in successive rows
The easy way to do this is A = diff(a);

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How can i use fill3 to make a box
That's odd. I cut and pasted the code from your question and ran it. It produced a blue rectangle in the z=0 plane, which I th...

Data saving for a loop
Nertila -- Yes, that is what this code does. Maybe it would be more clear if I wrote it in this way, with the k-index being the ...

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Data saving for a loop
a = zeros(n,n,n) for i=1:n %calculus for j=1:n %calculus for k=1:n %calculus ...

Why do I get this error?
One of the first two terms on the right should have an i+1 rather than i-1, but this is undoubtedly not the problem that caused ...

Creating a loop to determine at which iteration an error has occurred
You don't necessarily need a loop for this. You can use B = diff(A) to return the differences between each pair of successive v...

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How rotate a cylinder?
Lorenzo -- If all you need is to have the center of the cylinder located at the origin of the coordinate system, then what you n...

How to use bar() to plot
I suspect the arguments to your plot() functions are reversed, When you type plot(a,b), Matlab puts 'a' on the x-axis ahd 'b' o...

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Matlab question, very stuck
Your program seems to be a little uncertain about whether v is a number or a vector, and it also doesn't assign the values corre...

Plotting square wave in matlab
Yes, the function square(x) returns a unique value, either +1 or -1, for each vallue of x. There is no value of x for which it ...

How to do integral for data
I have two comments: A more correct statement about the integral is that the integral of sin(x) is equal to C-cos(x), where C i...