org: Column formulas
3.5.6 Column formulas
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When you assign a formula to a simple column reference like ‘$3=’, the
same formula will be used in all fields of that column, with the
following very convenient exceptions: (i) If the table contains
horizontal separator hlines with rows above and below, everything before
the first such hline is considered part of the table _header_ and will
not be modified by column formulas. Therefore a header is mandatory
when you use column formulas and want to add hlines to group rows, like
for example to separate a total row at the bottom from the summand rows
above. (ii) Fields that already get a value from a field/range formula
will be left alone by column formulas. These conditions make column
formulas very easy to use.
To assign a formula to a column, type it directly into any field in
the column, preceded by an equal sign, like ‘=$1+$2’. When you press
<TAB> or <RET> or ‘C-c C-c’ with the cursor still in the field, the
formula will be stored as the formula for the current column, evaluated
and the current field replaced with the result. If the field contains
only ‘=’, the previously stored formula for this column is used. For
each column, Org will only remember the most recently used formula. In
the ‘#+TBLFM:’ line, column formulas will look like ‘$4=$1+$2’. The
left-hand side of a column formula can not be the name of column, it
must be the numeric column reference or ‘$>’.
Instead of typing an equation into the field, you may also use the
following command:
‘C-c = (org-table-eval-formula)’
Install a new formula for the current column and replace current
field with the result of the formula. The command prompts for a
formula, with default taken from the ‘#+TBLFM’ line, applies it to
the current field and stores it. With a numeric prefix
argument(e.g., ‘C-5 C-c =’) the command will apply it to that many
consecutive fields in the current column.
Info Catalog
org: Field and range formulas
org: The spreadsheet
org: Lookup functions