Ragged Rows In Math Environment
pmatrix, aligned, cases, …) do not all have the same number of &-separated cells.
Q-22-10 — Ragged Rows In Math Environment
The rows of a math environment (
pmatrix,aligned,cases, …) do not all have the same number of&-separated cells.
What this means
Matrices and alignments are grids; a short row is padded with empty cells so the grid stays rectangular, and the padding is reported here. The output is usually what was intended, but the padding may hide a missing &.
Why this happens
Common causes: a forgotten & in one row, a \\ that ended a row early, or an extra & in one row.
How to fix it
Give every row the same number of cells, using empty cells (a & & c) where a position should stay blank.
Where it is reported
Math diagnostics point into the .qmd at the exact characters inside the
$…$ or $$…$$ block, including math that spans several lines or sits
inside a block quote or list item. When a \newcommand macro is involved,
a problem inside the macro body points at the definition and a problem in
a macro argument points at the use.