Top "Matrix" questions

How to convert a huge list-of-vector to a matrix more efficiently?

I have a list of length 130,000 where each element is a character vector of length 110. I would like to convert …

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Difference between numpy.array shape (R, 1) and (R,)

In numpy, some of the operations return in shape (R, 1) but some return (R,). This will make matrix multiplication more …

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Iterating over Numpy matrix rows to apply a function each?

I want to be able to iterate over the matrix to apply a function to each row. How can I …

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Create dataframe from a matrix

How to get a data frame with the same data as an already existing matrix has? A simplified example of …

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Android: How to rotate a bitmap on a center point

I've been looking for over a day for a solution to this problem but nothing helps, even the answers here. …

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Extract matrix column values by matrix column name

Is it possible to get a matrix column by name from a matrix? I tried various approaches such as myMatrix["…

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How to turn a vector into a matrix in R?

I have a vector with 49 numeric values. I want to have a 7x7 numeric matrix instead. Is there some sort …

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How do you dynamically allocate a matrix?

How do you dynamically allocate a 2D matrix in C++? I have tried based on what I already know: #include &…

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Appending a list to a list of lists in R

I'm having issues appending data to a list which is already in a list format. I have a program which …

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Python Inverse of a Matrix

How do I get the inverse of a matrix in python? I've implemented it myself, but it's pure python, and …

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