Block matrix

[DanielVolinski]

Hi All,

Is there any way to display a block matrix in LibreOffice Math?

Let say I have a 4x4 matrix, I want to display a vertical dotted line that separates the first two columns from the last two columns and a horizontal dotted line that separates the first two rows from the last two rows so as to have four different 2x2 matrices that make up the 4x4 block matrix. How do I do that?

Thanks,

Daniel

[ajlittoz]

This is a bit tedious. The trick is to add new matrix elements (cells) where you insert your “decorations”. Here’s what it looks like:

The formula is structured as:

 left [     -- left outer bracket
matrix {                     --  outer matrix
  matrix { left [ { a #  b ## c # d } right ]    -- NW element
 # dotsvert                  -- fake top center element
 # left [ B right ]          -- NE element
 ## dotsaxis # ` # dotsaxis  -- fake center row
 ##                          -- next row
 left [ C right ]            -- SW element
 # dotsvert                  -- fake bottom center element
 # left [ D right ]          -- SE element
 }                           -- close outer matrix
 right ]    -- right outer bracket

I added comments with --, but this is not part of Math syntax.

Eventually, you can “dim” the dots with silver attributes if you find them too bold.

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