Tag: numpy

Extract row from a data frame and make it a new data frame

I have a data frame like this Now, I need first row of data frame and make it another data frame like Answer Use DataFrame.iloc like: For Series:

Store slice of 3D Numpy Array as a variable

numpy python

I’ve got various 3D arrays that I’m viewing 2D slices of, along either the X, Y or Z axis. To simplify my code, I would like to have one location of declaring the slice such as and choose which view to run in my script. Then the rest of my code can apply the myview slice when visualizing, There&#8…

Solving linear equation of complex matrices

complex-numbers linear-algebra numpy python

I have a linear equation of a form ax=b where b is a complex matrix, and a is a real matrix. I’m expecting solution x to be a complex vector. When trying the numpy.linalg.solve(a,b) function, I’m getting this warning: ComplexWarning: Casting complex values to real discards the imaginary part How d…

Create np.array filled with zero arrays

numba numpy python

I’m trying to initialize an “empty” array with each elements containing t_list a 8×8 np.zeros array : t_list = np.zeros((8,8), dtype=np.float32) I would now want to have a np.array with multiple t_list at each indexes: result = np.array((t_list, t_list, …., tlist)) I would like to…

The most efficient way to sum all possible pairs (x_ik, y_j) for a given k?

algorithm arrays numpy pandas python

I have two numpy array x with shape (n,m) and y with shape (p,). I would like to sum all possible pairs x[k, i] and y[j] to create a new numpy array z with shape (n, m*p). A naïve algorithm would be : This algorithm has a polynomial complexity : O(n*m*p) Knowing I am working on array with $n ~

Numpy array: iterate through column and change value based on the current value and the next value

iteration numpy python

I have an array like this: This is an extension of a recent question that I asked elsewhere here. I have a numpy array like this: In the third column, I want the value to be replaced with 10001 if the next one along is 101 AND if the current one is 6. which would result in an array like

Matplotlib with variable upper limit

contour data-visualization matplotlib numpy python

I need to contourplot one huge expression which is: which is not so much relevant here. Usually the task is trivial and can be done this way: That all in common yields which is okay, but I have an issue I cannot handle. The problem is that I need to plot it assuming that my y is not a simple

Plotting a particular set of contour line at desired point or location

contour matplotlib numpy python seaborn

I want a contour plot showing contour levels corresponding to a particular set of x,y. I tried increasing the number of contour lines but it doesn’t give the contour line near the required point. I want to get a contour line to suppose around (0.1,0.1) but am not able to do so, I tried increasing the nu…

Use lambda with multi input with numpy.apply_along_axis

numpy python python-3.x

Here is my code: But the above way will give me error, missing 2 required positional arguments. I have tried to do like this: It works but every time when I need to do computation on the array element, I need to type the index, it is quite redundant. Is there any way that I can pass the array axis