When inserting ={1;2|3;4} instead of getting a 2x2 matrix a column vector of 4x1 as ={1;2;3;4} is obtained. In different words: if working as in https://help.libreoffice.org/Calc/Array_Functions#Using_Inline_Array_Constants_in_Formulas is explained wrong answer is obtained.
Please have a look at the settings in Tools > Options > Calc > Formula, section "Separators". To enter it as ={1;2|3;4} you need the settings Array column ; Array row | The help has the text The column separator (separating elements in one row) and the row separator are language and locale dependent. But in this help content, the ';' semicolon and '|' pipe symbol are used to indicate the column and row separators, respectively. For example, in the English locale, the ',' comma is used as the column separator, while the ';' semicolon is used as the row separator. The help misses the above mentioned settings. Therefore I put this as bug in documentation. The feature itself works without problem.
Thanks Regina. Bst Rds.
Bug fixed by Steve Fanning https://help.libreoffice.org/7.0/en-US/text/scalc/01/04060107.html?DbPAR=CALC#bm_id3147273 https://opengrok.libreoffice.org/xref/help/source/text/scalc/01/04060107.xhp?a=true&r=2736ed30#128