queries

Extract data from a DafReader . See the Julia documentation for details.

class dafpy.queries. And ( property : str )

A query operation for restricting the set of entries of an Axis . See the Julia documentation for details.

class dafpy.queries. AndNot ( property : str )

Same as And but use the inverse of the mask. See the Julia documentation for details.

class dafpy.queries. AsAxis ( axis : str | None = None )

There are three cases where we may want to take a vector property and consider each value to be the name of an entry of some axis: Fetch , CountBy and GroupBy . See the Julia documentation for details.

class dafpy.queries. Axis ( axis : str )

A query operation for specifying a result axis. See the Julia documentation for details.

class dafpy.queries. CountBy ( property : str )

A query operation that generates a matrix of counts of combinations of pairs of values for the same entries of an axis. See the Julia documentation for details.

class dafpy.queries. Fetch ( property : str )

A query operation for fetching the value of a property from another axis, based on a vector property whose values are entry names of the axis. See the Julia documentation for details.

class dafpy.queries. GroupBy ( property : str )

A query operation that uses a (following) ReductionOperation to aggregate the values of each group of values. See the Julia documentation for details.

class dafpy.queries. IfMissing ( missing_value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str , * , type : Type | None = None )

A query operation providing a value to use if the data is missing some property. See the Julia documentation for details.

class dafpy.queries. IfNot ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str | None = None )

A query operation providing a value to use for “false-ish” values in a vector (empty strings, zero numeric values, or false Boolean values). See the Julia documentation for details.

class dafpy.queries. IsEqual ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str )

Equality is used for two purposes: As a comparison operator, similar to IsLess except that uses = instead of < for the comparison; and To select a single entry from a vector. See the Julia documentation for details.

class dafpy.queries. IsGreater ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str )

Similar to IsLess except that uses > instead of < for the comparison. See the Julia documentation for details.

class dafpy.queries. IsGreaterEqual ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str )

Similar to IsLess except that uses >= instead of < for the comparison. See the Julia documentation for details.

class dafpy.queries. IsLess ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str )

A query operation for converting a vector value to a Boolean mask by comparing it some value. See the Julia documentation for details.

class dafpy.queries. IsLessEqual ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str )

Similar to IsLess except that uses <= instead of < for the comparison. See the Julia documentation for details.

class dafpy.queries. IsMatch ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str )

Similar to IsLess except that the compared values must be strings, and the mask is of the values that match the given regular expression. See the Julia documentation for details.

class dafpy.queries. IsNotEqual ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str )

Similar to IsLess except that uses != instead of < for the comparison. See the Julia documentation for details.

class dafpy.queries. IsNotMatch ( value : bool | int | float | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | float32 | float64 | str )

Similar to IsMatch except that looks for entries that do not match the pattern. See the Julia documentation for details.

class dafpy.queries. Lookup ( property : str )

A query operation for looking up the value of a property with some name. See the Julia documentation for details.

class dafpy.queries. MaskSlice ( axis : str )

A query operation for using a slice of a matrix as a mask, when the other axis of the matrix is different from the mask axis. See the Julia documentation for details.

class dafpy.queries. Names ( kind : str | None = None )

A query operation for looking up a set of names. See the Julia documentation for details.

class dafpy.queries. Or ( property : str )

A query operation for expanding the set of entries of an Axis . See the Julia documentation for details.

class dafpy.queries. OrNot ( property : str )

Same as Or but use the inverse of the mask. See the Julia documentation for details.

dafpy.queries. Query

A Python class to use instead of Julia’s Daf.Query . See the Julia documentation for details.

alias of Union [ Axis , Lookup , Names , QuerySequence ]

dafpy.queries. parse_query ( query_string : str ) → QuerySequence

Parse a query_string into a QuerySequence .

If you want something like the q prefix used in Julia, write from dafpy import parse_query as q .

class dafpy.queries. SquareMaskColumn ( value : str )

Similar to MaskSlice but is used when the mask matrix is square and we’d like to use a column as a mask. See the Julia documentation for details.

class dafpy.queries. SquareMaskRow ( value : str )

Similar to MaskSlice but is used when the mask matrix is square and we’d like to use a row as a mask. See the Julia documentation for details.

class dafpy.queries. Xor ( property : str )

A query operation for flipping the set of entries of an Axis . See the Julia documentation for details.

class dafpy.queries. XorNot ( property : str )

Same as Xor but use the inverse of the mask. See the Julia documentation for details.

dafpy.queries. query_result_dimensions ( query : str | Axis | Lookup | Names | QuerySequence ) → int

Return the number of dimensions (-1 - names, 0 - scalar, 1 - vector, 2 - matrix) of the results of a query. See the Julia documentation for details.