Say I have two matrices A and B. For example, Is there a way to append A and B? Answer It sounds to me like you’re looking for np.hstack: np.vstack will work if you want to stack them downward:
Tag: matrix
Pandas dataframe.dot division method
I am trying to divide two series of different length to return the matrix product dataframe of them. I can multiply them using the dot method (from this answer): I’ve tried the div method, but this just fills the dataframe with NaNs: Likewise the standard division operator also returns the same result: So I’m a bit stumped as to what
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 tedious since explicit reshape is required. For example, given a matrix M, if we want to do numpy.dot(M[:,0], numpy.ones((1, R))) where R is the number of rows (of course, the same issue also occurs column-wise). We will get matrices
Get diagonal without using numpy?
I’m trying to get the diagonal from a matrix in Python without using numpy (I really can’t use it). Does someone here knows how to do it? Example of what I want to get: Or like: Until know I’ve tried a lot of stuff but doesn’t work. If direc==1 I need to get the diagonal that goes from left-> right,
Create a 2D list out of 1D list
I am a bit new to Python and I want to convert a 1D list to a 2D list, given the width and length of this matrix. Say I have a list=[0,1,2,3] and I want to make a 2 by 2 matrix of this list. How can I get matrix [[0,1],[2,3]] width=2, length=2 out of the list? Answer Try something
How can I find the dimensions of a matrix in Python?
How can I find the dimensions of a matrix in Python. Len(A) returns only one variable. Edit: Is (I assume) generating a matrix of integers (less likely strings). I need to find the size of that matrix, so I can run some tests without having to iterate through all of the elements. As far as the data type goes, I
Pretty print 2D list?
Is there a simple, built-in way to print a 2D Python list as a 2D matrix? So this: would become something like I found the pprint module, but it doesn’t seem to do what I want. Answer To make things interesting, let’s try with a bigger matrix: Output: UPD: for multiline cells, something like this should work: And then apply
Adding row/column headers to NumPy arrays
I have a NumPy ndarray to which I would like to add row/column headers. The data is actually 7x12x12, but I can represent it like this: where A is my 2x6x6 array. How do I insert headers across the first row and the first column, so that each array looks like this in my CSV output file? What I have
Matrix in python
I am very new to Python, I need to read numbers from a file and store them in a matrix like I would do it in fortran or C; How can I do the same in Python? I read a bit but got confused with tuples and similar things If you could point me to a similar example it would