Struct DStdevFn 

pub struct DStdevFn;

Trait Implementations

impl Debug for DStdevFn

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Function for DStdevFn

Returns the sample standard deviation of a database field for matching records.

DSTDEV computes standard deviation with the sample denominator (n - 1) after criteria filtering.

Remarks

• Criteria rows represent OR branches; criteria columns in each row are combined with AND.
• field is resolved by case-insensitive header text or 1-based column index; invalid field resolution returns #VALUE!.
• At least two numeric values must match criteria, otherwise the result is #DIV/0!.

Examples

title: "Sample stdev of units for East or West"
grid:
  A1: "Region"
  B1: "Salesperson"
  C1: "Product"
  D1: "Units"
  E1: "Revenue"
  A2: "West"
  B2: "Diaz"
  C2: "Widget"
  D2: 24
  E2: 126000
  A3: "East"
  B3: "Patel"
  C3: "Gadget"
  D3: 31
  E3: 142500
  A4: "North"
  B4: "Kim"
  C4: "Widget"
  D4: 18
  E4: 87000
  A5: "West"
  B5: "Ramos"
  C5: "Service"
  D5: 12
  E5: 46000
  A6: "South"
  B6: "Lee"
  C6: "Gadget"
  D6: 27
  E6: 119000
  A7: "East"
  B7: "Noor"
  C7: "Widget"
  D7: 22
  E7: 101000
  G1: "Region"
  G2: "East"
  G3: "West"
formula: "=DSTDEV(A1:E7, \"Units\", G1:G3)"
expected: 7.847504911329036

title: "Sample stdev of widget revenue"
grid:
  A1: "Region"
  B1: "Salesperson"
  C1: "Product"
  D1: "Units"
  E1: "Revenue"
  A2: "West"
  B2: "Diaz"
  C2: "Widget"
  D2: 24
  E2: 126000
  A3: "East"
  B3: "Patel"
  C3: "Gadget"
  D3: 31
  E3: 142500
  A4: "North"
  B4: "Kim"
  C4: "Widget"
  D4: 18
  E4: 87000
  A5: "West"
  B5: "Ramos"
  C5: "Service"
  D5: 12
  E5: 46000
  A6: "South"
  B6: "Lee"
  C6: "Gadget"
  D6: 27
  E6: 119000
  A7: "East"
  B7: "Noor"
  C7: "Widget"
  D7: 22
  E7: 101000
  G1: "Product"
  G2: "Widget"
formula: "=DSTDEV(A1:E7, 5, G1:G2)"
expected: 19756.85535031659

related:
  - DSTDEVP
  - DVAR
  - STDEV.S
faq:
  - q: "Why does DSTDEV return #DIV/0! with one matching row?"
    a: "DSTDEV uses sample statistics and needs at least two numeric matches for an n-1 denominator."

[formualizer-docgen:schema:start] Name: DSTDEV Type: DStdevFn Min args: 3 Max args: 1 Variadic: false Signature: DSTDEV(arg1: any@scalar) Arg schema: arg1{kinds=any,required=true,shape=scalar,by_ref=false,coercion=None,max=None,repeating=None,default=false} Caps: PURE, REDUCTION [formualizer-docgen:schema:end]

fn caps(&self) -> FnCaps

Capability flags for this function

fn name(&self) -> &'static str

fn min_args(&self) -> usize

fn variadic(&self) -> bool

fn arg_schema(&self) -> &'static [ArgSchema]

fn eval<'a, 'b, 'c>( &self, args: &'c [ArgumentHandle<'a, 'b>], ctx: &dyn FunctionContext<'b>, ) -> Result<CalcValue<'b>, ExcelError>

The unified evaluation path.

fn namespace(&self) -> &'static str

fn volatile(&self) -> bool

fn aliases(&self) -> &'static [&'static str]

Optional list of additional alias names (case-insensitive) that should resolve to this function. Default: empty slice. Implementors can override to expose legacy names. Returned slice must have ’static lifetime (typically a static array reference).

fn function_salt(&self) -> u64

fn eval_reference<'a, 'b, 'c>( &self, _args: &'c [ArgumentHandle<'a, 'b>], _ctx: &dyn FunctionContext<'b>, ) -> Option<Result<ReferenceType, ExcelError>>

Optional reference result path. Only called by the interpreter/engine when the callsite expects a reference (e.g., range combinators, by-ref argument positions, or spill sources).

fn dispatch<'a, 'b, 'c>( &self, args: &'c [ArgumentHandle<'a, 'b>], ctx: &dyn FunctionContext<'b>, ) -> Result<CalcValue<'b>, ExcelError>

Dispatch to the unified evaluation path with automatic argument validation.