vectorial | Vector math library with NEON/SSE support | Math library

How may I obtain the same functionality as grepl within a vectorial conditional statement?

I wish to transform raw data of geographical divisions (mixed with other categories) by prepending the city name where it is missing from district names:

I am looking for finding or rather building common eigenvectors matrix X between 2 matrices A and B such as :

Consider the following problem:

I am now in the third part of this question. I wrote the vectorial loop equations (q=teta2, x=teta3 and y=teta4):

Considering the following Leapfrog scheme used to discretize a vectorial wave equation with given initial conditions and periodic boundary conditions. I have implemented the scheme and now I want to make numerical convergence tests to show that the scheme is of second order in space and time.

I'm mainly struggling with two points here:

1. I'm not 100% sure if I implemented the scheme correctly. I really wanted to use slicing because it is so much faster than using loops.
2. I don't really know how to get the right error plot, because I'm not sure which norm to use. In the examples I have found (they were in 1D) we've always used the L2-Norm.

I wrote code for Runge-Kutta 4 for solving system of ODEs.
It works fine for 1-D ODE but when I try to solve x'' + kx = 0 I have a problem trying to define a vectorial function:

Let u1 = x and u2 = x' = u1', then the system looks like:

I'm trying to plot a phase plane and I want it to look nice, however some solutions of the system of equations diverge because of the initial conditions. Is there some way that I can make a try/except chain in order when the solution diverges it doesn't plot it. Here is my code:

I'm trying to do exactly what this question asked for R in Python: Different hard threshold for each column That is, apply a different threshold per column on an $n\times m$ numpy array.

The only way I know is to iterate over the columns but there must be a vectorial way to do it (perhaps using views or strides)?

I have a question on solving second order differential equations using RK4, considering additional constraints on the first derivative. I am doing the example shown here with some modifications

θ′′(t) + b θ′(t) + c sin(θ(t)) = 0

The additional constraint is:

when θ_i θ_(i+1)<0, then θ′_(i+1)=0.9θ′_i,

where i is the steps of t, i+1 is one step after i. In the real world, it says when the direction of displacement reverses, its velocity is reduced to 90%.

Vectorially if y(t) = (θ(t), ω(t)), then the equation is ẏ = f(t,y), where f(t,y) = (y₂(t), −by₂(t) − cos(y₁(t))).

In this problem, how should I modify the code if I want to add constraints on ω or θ′(t) (which are the same thing)? Here is my code which didn't work. The additional condition makes θ′ non-continuous. The following "homemade" solution cannot update θ′ properly. I am new to Python and this is my first StackOverflow post. Any guidance is much appreciated.

As provided in the image i know co-ordinates of two points A(x1, y1) and C(x2, y2), and also i have distance D from C to third point i.e B(x, y) and the angle thetha made by three points. Here thetha can range from 0 to 360.

Please i need the know third point from the following data given, any code would be helpful.

As i have tried the possible way using the method provided in the following link i was not able to find correct result

Javascript function to find third point of triangle when all sides, angles and first two points are known

PS.

Vectorial answers is cool, but I use javascript and don't know how to add vectors over there.