datagrok-calc-column

name

datagrok-calc-column

description

Add a calculated, formula-based column to a dataframe inside a datagrok-exec block. Use whenever the user asks to compute, derive, add, or create a new column from existing columns — LipE, ratios, log/round, heavy atom count, any expression in the Datagrok formula DSL. Replaces hand-written addNewFloat/addNewInt + for-loop with a single formula-attached column that recomputes when source columns change.

datagrok-calc-column

Use t.columns.addNewCalculated(name, formula, type?) inside a datagrok-exec block to add a formula-driven column. The formula stays attached to the column, so edits to source columns trigger automatic recompute.

Do not use t.columns.addNewFloat('LipE') plus a manual for loop — that produces a static column with no formula and no recompute.

Signature

await t.columns.addNewCalculated(
  name,              // string
  formula,           // string — DSL, see below
  type?,             // 'auto' (default) | 'double' | 'int' | 'string' | 'bool' | 'datetime'
  treatAsString?,    // boolean — wraps formula in quotes
): Promise<DG.Column>

t is the current DG.DataFrame (injected by datagrok-exec). If you have a DataFrame from elsewhere, replace t with that variable.

Formula DSL — quick reference

Form	Meaning
${ColumnName}	per-row scalar reference, exact case
$[ColumnName]	whole-column reference (use inside aggregates)
row	current row index
+ - * / ^	operators
Round, RoundFloat, Log, Log10, Sqrt, Abs	math functions
Avg($[col]), Sum($[col]), Min($[col]), Max($[col]), StDev($[col])	aggregates over a whole column
Max([${A}, ${B}]), Min([${A}, ${B}])	per-row max / min across columns — the argument is an array
Chem:getInchis(${molecule}), HeavyAtomCount(${molecule})	only functions tagged vectorFunc: 'true' work here — see Which functions work in a formula
"text"	string literal (double quotes)

Both operator and function forms parse: ${pIC50} - ${cLogP} ≡ Sub(${pIC50}, ${cLogP}).

Full function catalog: help/transform/add-new-column.md.

Examples

// Heavy atom count (requires Chem package)
await t.columns.addNewCalculated('HAC', 'HeavyAtomCount(${molecule})', 'int');

// Log of activity
await t.columns.addNewCalculated('logIC50', 'Log10(${IC50})');

// Per-row maximum of two columns — note the array argument.
await t.columns.addNewCalculated('CS max', 'Max([${Chemical Space X}, ${Chemical Space Y}])');

Which functions work in a formula

A package function (Chem:foo, Admetica:bar, ...) can be used inside an addNewCalculated formula only if it is tagged vectorFunc: 'true' in its metadata. Everything else must be called imperatively via grok.functions.call(...) in a separate datagrok-exec block.

Chem properties → use the chem catalog, not a formula

For molecular properties (MW, LogP, LogS, HBA, HBD, PSA, rotatable bonds, stereo centers, molecule charge): use Chem:addChemPropertiesColumns (boolean flags) or Chem:getProperties(molecules, selected?) (string list) — see datagrok-chem-toolkit. Example:

await grok.functions.call('Chem:addChemPropertiesColumns', {
  table: t, molecules: t.col('smiles'), MW: true,
});

What this skill does NOT do

• It does not filter, sort, or select rows — those are separate skills.
• It does not add viewers — use grok.shell.addViewer(...) or a future viewer skill.
• It does not run server-side scripts — use grok.functions.call(...) or the script's registered name.