Creating a Binary Matrix with C++ Code

[jetoso]

I want to build a binary matrix (with 1 and 0 entries) with all possible combinations, say for example if n is the number of entries of one row of the matrix, then 2^n is the total number of different entries in the matrix.

For instance, for n=3, 2^n = 8, so we would have the following matrix
[ 1 0 0
0 1 0
0 0 1
1 1 0
1 0 1
0 1 1
1 1 1
0 0 0 ]

I am writing a C++ code but I have not figured out how to make it. Any suggestions?

 

[Jimmy Snyder]

Do you plan to go beyond n = 32? If so, I don't think the project is practical. If not, then you can simply loop through the integers from 0 to (2^n - 1) and print out their bits. I haven't tried this code, but it might work. If the order of the lines matters, then you can manipulate things as needed.

// print the bit patterns for the first 2^n integers
for (int wRow = 0; wRow < (2^n); ++wRow)
{
  // make a copy of the row number
  int wBitMap = wRow;

  // for each bit
  for (int wBit = 0; wBit < n; ++wBit)
  {
    // display the leftmost bit along with a space character
    cout << wBitMap & 1 << " ";
    // and shift a new bit into place
    wBitMap /= 2;
  }
  cout << endl;
}

 

[ravenprp]

Creating a binary matrix with all possible combinations can be achieved using nested for loops in C++. The outer loop will iterate through the rows of the matrix and the inner loop will iterate through the columns. For each cell in the matrix, we can use the binary representation of the current iteration number to determine whether the cell should contain a 1 or a 0.

Here is a possible implementation:

#include <iostream>
#include <cmath>

using namespace std;

int main() {
// Get input for n
int n;
cout << "Enter the number of entries for one row of the matrix: ";
cin >> n;

// Calculate the total number of combinations
int total_combinations = pow(2, n);

// Create the matrix with n rows and total_combinations columns
int matrix[n][total_combinations];

// Loop through the rows
for (int i = 0; i < n; i++) {
// Loop through the columns
for (int j = 0; j < total_combinations; j++) {
// Get the binary representation of the current iteration number
int binary = j;
int index = n - 1;
// Fill the matrix with 1s and 0s based on the binary representation
while (index >= 0) {
matrix[j] = binary % 2;
binary /= 2;
index--;
}
}
}

// Print the matrix
for (int i = 0; i < n; i++) {
for (int j = 0; j < total_combinations; j++) {
cout << matrix[j] << " ";
}
cout << endl;
}

return 0;
}

This code will create a matrix with n rows and 2^n columns, filled with all possible combinations of 1s and 0s. The binary representation of the current iteration number is used to determine the values in each cell, with 1 representing a 1 and 0 representing a 0. I hope this helps in your code development.