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Let $M\in\{-1,0,+1\}^{n\times n}$ be a matrix of rank $r$.

Consider the matrix $f(M)\in\{0,+1\}^{mn\times mn}$ where $0$ in $M$ is replaced by $m\times m$ all $0$ matrix, $+1$ in $M$ is replaced by $m\times m$ identity matrix and $-1$ in $M$ is replaced by $m\times m$ anti-identity matrix (anti-diagonal matrix having $1$s on anti-diagonal whose square is identity).

Example at $m=2$:

$0$ is replaced by $\begin{bmatrix}0&0\\0&0\end{bmatrix}$, $+1$ is replaced by $\begin{bmatrix}1&0\\0&1\end{bmatrix}$ and $-1$ is replaced by $\begin{bmatrix}0&1\\1&0\end{bmatrix}$.

  1. Is the real rank of the new matrix $O(r)$? Is there a precise bound?
  1. Is the $\mathbb F_2$ rank of the new matrix $O(r)$? Is there a precise bound?

On the real and finite field rank of a $0/1$ matrix - II

Let $M\in\{-1,0,+1\}^{n\times n}$ be a matrix of rank $r$.

Consider the matrix $f(M)\in\{0,+1\}^{mn\times mn}$ where $0$ in $M$ is replaced by $m\times m$ all $0$ matrix, $+1$ in $M$ is replaced by $m\times m$ identity matrix and $-1$ in $M$ is replaced by $m\times m$ anti-identity matrix (anti-diagonal matrix having $1$s on anti-diagonal whose square is identity).

Example at $m=2$:

$0$ is replaced by $\begin{bmatrix}0&0\\0&0\end{bmatrix}$, $+1$ is replaced by $\begin{bmatrix}1&0\\0&1\end{bmatrix}$ and $-1$ is replaced by $\begin{bmatrix}0&1\\1&0\end{bmatrix}$.

  1. Is the real rank of the new matrix $O(r)$? Is there a precise bound?
  1. Is the $\mathbb F_2$ rank of the new matrix $O(r)$? Is there a precise bound?

Let $M\in\{-1,0,+1\}^{n\times n}$ be a matrix of rank $r$.

Consider the matrix $f(M)\in\{0,+1\}^{mn\times mn}$ where $0$ in $M$ is replaced by $m\times m$ all $0$ matrix, $+1$ in $M$ is replaced by $m\times m$ identity matrix and $-1$ in $M$ is replaced by $m\times m$ anti-identity matrix (anti-diagonal matrix having $1$s on anti-diagonal whose square is identity).

Example at $m=2$:

$0$ is replaced by $\begin{bmatrix}0&0\\0&0\end{bmatrix}$, $+1$ is replaced by $\begin{bmatrix}1&0\\0&1\end{bmatrix}$ and $-1$ is replaced by $\begin{bmatrix}0&1\\1&0\end{bmatrix}$.

  1. Is the real rank of the new matrix $O(r)$? Is there a precise bound?
  1. Is the $\mathbb F_2$ rank of the new matrix $O(r)$? Is there a precise bound?

On the real and finite field rank of a $0/1$ matrix - II

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Turbo
  • 13.9k
  • 1
  • 27
  • 76

On the real and finite field rank of a $0/1$ matrix - I

Source Link
Turbo
  • 13.9k
  • 1
  • 27
  • 76

On the real and finite field rank of a $0/1$ matrix

Let $M\in\{-1,0,+1\}^{n\times n}$ be a matrix of rank $r$.

Consider the matrix $f(M)\in\{0,+1\}^{mn\times mn}$ where $0$ in $M$ is replaced by $m\times m$ all $0$ matrix, $+1$ in $M$ is replaced by $m\times m$ identity matrix and $-1$ in $M$ is replaced by $m\times m$ anti-identity matrix (anti-diagonal matrix having $1$s on anti-diagonal whose square is identity).

Example at $m=2$:

$0$ is replaced by $\begin{bmatrix}0&0\\0&0\end{bmatrix}$, $+1$ is replaced by $\begin{bmatrix}1&0\\0&1\end{bmatrix}$ and $-1$ is replaced by $\begin{bmatrix}0&1\\1&0\end{bmatrix}$.

  1. Is the real rank of the new matrix $O(r)$? Is there a precise bound?
  1. Is the $\mathbb F_2$ rank of the new matrix $O(r)$? Is there a precise bound?