The basic operations of OpenCV is to draw over images. The ability to add different geometric shapes just like lines, circles and rectangle etc. Often working with image analysis, we want to highlight a portion of the image, for example by adding a rectangle that defines that portion. Also as example an arrow to indicate something. cv2.line() − This function is used to draw line on an image. cv2.rectangle() − This function is used to draw rectangle on an image. cv2.circle() − This function is used to draw circle on an image. cv2.putText() − This function is used to write ... Read More

To rename files in Python, use the rename() method of the os module. The parameters of the rename() method are the source_address (old name) and the destination_address (new name). Install and Import the OS module To install the OS module − pip install os To import − import os Rename multiple files using rename() method The rename() method can be easily used to rename multiple files − Example import os # Function to rename multiple files def main(): i = 0 path="E:/amit/" for filename in os.listdir(path): my_dest ="new" + str(i) + ".jpg" my_source =path + filename my_dest =path ... Read More

There is no such thing as a static class in C++. The closest approximation is a class that only contains static data members and static methods.Static data members in a class are shared by all the class objects as there is only one copy of them in the memory, regardless of the number of objects of the class. Static methods in a class can only access static data members, other static methods or any methods outside the class.A program that demonstrates static data members and static methods in a class in C++ is given as follows. Example #include ... Read More

The size of a data type can be obtained using sizeof(). A program that demonstrates the printing of the array parameter in a function in C++ is given as follows.Example Live Demo#include using namespace std; int func(int a[]) {    cout

Static objects are declared with the keyword static. They are initialized only once and stored in the static storage area. The static objects are only destroyed when the program terminates i.e. they live until program termination.A program that demonstrates static objects in C++ is given as follows.Example Live Demo#include using namespace std; class Base {    public :    int func() {       int a = 20;       cout

The static variables in member functions are declared using the keyword static. The space for the static variables is allocated only one time and this is used for the entirety of the program. Also, there is only one copy of these static variables in the whole program.A program that demonstrates static variables in member functions in C++ is given as follows.Example Live Demo#include using namespace std; class Base {    public :    int func() {       static int a;       static int b = 12;       cout

Combination and permutation are a part of Combinatorics. Permutation is the different arrangements that a set of elements can make if the elements are taken one at a time, some at a time or all at a time. Combination is is the different ways of selecting elements if the elements are taken one at a time, some at a time or all at a time.Number of permutations when there are total n elements and r elements need to be arranged.Number of combinations when there are total n elements and r elements need to be selected.A program that calculates combination and ... Read More

A double can be converted into a string in C++ using std::to_string. The parameter required is a double value and a string object is returned that contains the double value as a sequence of characters.A program that demonstrates this in C++ is given as follows.Example Live Demo#include #include using namespace std; int main() {    double d = 238649.21316934;    string s = to_string(d);    cout

Static C++ member variables are defined using the static keyword. The static member variables in a class are shared by all the class objects as there is only one copy of them in the memory, regardless of the number of objects of the class.The static class member variables are initialized to zero when the first object of the class is created if they are not initialized in any other way.A program that demonstrates static member variables and their initialization in C++ is given as follows.Example Live Demo#include using namespace std; class Demo {    public :    static int num; ... Read More

An array can be created using all data types such as int, char, float, double etc. But creating an array by using the void data type is not possible. An error will be displayed if that is done.A program that demonstrates this is given as follows.Example Live Demo#include #include int main() {    void arr1[4];    printf("A void array");    return 0; }OutputThe above program returns the following error.error: declaration of ‘arr1’ as array of voids void arr1[4];Now let us understand the above program.An array arr1 of void data type is created in the above program. Since this is ... Read More