C++ Tutorial/valarray/valarray resize

Remove all elements in a valarray

<source lang="cpp">/* The following code example is taken from the book

* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/

1. include <iostream>
2. include <valarray>

using namespace std; // print valarray template <class T> void printValarray (const valarray<T>& va) {

   for (int i=0; i<va.size(); i++) {
       cout << va[i] << " ";
   }
   cout << endl;

} int main() {

   // define two valarrays with ten elements
   valarray<double> va1(10), va2(10);
   // assign values 0.0, 1.1, up to 9.9 to the first valarray
   for (int i=0; i<10; i++) {
       va1[i] = i * 1.1;
   }
   // assign values of the first to the second valarray
   va2 = va1;
   // remove all elements of the first valarray
   va1.resize(0);
   // print both valarrays again
   printValarray(va1);
   printValarray(va2);

}</source>

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