Step function The step function is simple, it gets only two values zero or one no matter what the input value is. #!/usr/bin/env python import numpy as np import matplotlib.pylab as plt def step_function(x): return np.array(x>0, dtype=np.int) if __name__ == ‘__main__’: x = np.arange( -5, 5, 0.1 ) y = Read more…
We define all edges in the boundary have no neighbor cells. It indicates that there is no boundary on the closed surface. In the following example, I read an STL file and get an arch. Step 1, clip the original arch with a plane that has normal (0, 1, 0) Read more…
Almost every developer know how to implement the bubble sort for a simple array. We just need to travel over the array in two levels and swap the adjacent elements in the second level if their values’ order is not correct. The algorithm implement with Python is in the following Read more…
We often need to delete some elements in an STL set. But it causes a strange bug if we are careless sometimes. One newbie in C Plus Plus program language may write the following code to delete all odd numbers in a set. int main() { vector<int> vec{ 1, 3, Read more…
I want to get the solution of the equation Bisection Method The first algorithm for the problem is bisection method. The algorithm bisection method doesn’t require derivation for the equation. It just needs a possible solution range [l, r], then calculates the variable mid as , compares the result of Read more…
Driven class of unary_function can be used to check a single element based on special condition.Programmer can regard it as some algorithms’ parameter, such as count_if, find_if, and find_if_not.The following code shows how to write a customized unray class and use it. C++ struct Widget { int GetSpeed() const { return speed; } Widget( const Read more…
We need not sort all elements sometimes. Here are a few simple examples of STL algorithms partial_sort, nth_element, and partition. partial_sort For example, find the 5 biggest ones in 10 random numbers. #include <iostream> #include <vector> #include <cstdlib> #include <ctime> #include <algorithm> using namespace std; int main() { vector<int> values; Read more…
accumulate Interval algorithm accumulate supports custom calculate method to count elemeints in the special range. We can use it to get summary, multiple, average and etc of some elements, it’s very convenient and powerful. The syntax and usage example are in the following. Syntax: template< class InputIt, class T > Read more…
count STL algorithm count can help us to count the elements that are equal to value.Its syntax is like the following form: C++ template typename iterator_traits::difference_type count( InputIt first, InputIt last, const T &value ); Example: C++ #include #include #include using namespace std; int main(int argc, char *argv[]) { vector Read more…