Math & Science ⇒ Crossing out entire Rows or Columns in Matrices

[yakeyglee]

What's a good solution if I'm looking to cross out an entire row or column in a matrix or array environment? I'm trying to better visually describe the process of expansion by minors to calculate a determinant, which involves "deleting" entire rows and columns of a matrix. Thank you in advance!

[kaiserkarl13]

This isn't a particularly good solution, but it's an idea: draw the matrix, then put a zero-width, zero-height picture environment right below it with a \put command. Give the \put command a negative position, and draw the vertical/horizontal lines on top of the matrix by trial-and-error.

If someone knows of a package that does this automatically without the agonizing pain, I'm very curious to know what it is, but this will do it.