queries

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

class dafpy.queries. AndMask ( property : str )

Combine a mask with another, using the bitwise AND operator. See the Julia documentation for details.

class dafpy.queries. AndNegatedMask ( property : str )

Combine a mask with another, using the bitwise AND-NOT operator. See the Julia documentation for details.

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

A query operator for specifying that the values of a property we looked up are the names of entries in some axis. See the Julia documentation for details.

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

A query operator for specifying an axis. See the Julia documentation for details.

class dafpy.queries. BeginMask ( property : str )

Start specifying a mask to apply to an axis of the result. See the Julia documentation for details.

class dafpy.queries. BeginNegatedMask ( property : str )

Start specifying a mask to apply to an axis of the result, negating the first mask. See the Julia documentation for details.

class dafpy.queries. CountBy ( property : str )

Specify a second property for each vector entry, to compute a matrix of counts of the entries with each combination of values. See the Julia documentation for details.

class dafpy.queries. EndMask

Finish specifying a mask to apply to an axis of the result, following BeginMask or BeginNegatedMask . See the Julia documentation for details.

class dafpy.queries. GroupBy ( property : str )

Specify value per vector entry to group vector values by, must be followed by a ReductionOperation to reduce each group of values to a single value. See the Julia documentation for details.

class dafpy.queries. GroupColumnsBy ( property : str )

Specify value per matrix column to group the columns by, must be followed by a ReduceToColumn to reduce each group of columns to a single column. See the Julia documentation for details.

class dafpy.queries. GroupRowsBy ( property : str )

Specify value per matrix row to group the rows by, must be followed by a ReduceToRow to reduce each group of rows to a single row. See the Julia documentation for details.

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

A query operator for specifying a value to use for a property that is missing from the data. See the Julia documentation for details.

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

Specify a final value to use when, having looked up some base property values, we use them as axis entry names to lookup another property of that axis. See the Julia documentation for details.

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

Convert a vector of values to a vector of Booleans, is true for entries that are equal to the comparison_value . See the Julia documentation for details.

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

Convert a vector of values to a vector of Booleans, is true for entries that are greater than the comparison_value . See the Julia documentation for details.

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

Convert a vector of values to a vector of Booleans, is true for entries that are greater than or equal to the comparison_value . See the Julia documentation for details.

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

Convert a vector of values to a vector of Booleans, is true for entries that are less than the comparison_value . See the Julia documentation for details.

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

Convert a vector of values to a vector of Booleans, is true for entries that are less than or equal to the comparison_value . See the Julia documentation for details.

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

Convert a vector of values to a vector of Booleans, is true for (string!) entries that are a (complete!) match to the comparison_value regular expression. See the Julia documentation for details.

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

Convert a vector of values to a vector of Booleans, is true for entries that are not equal to the comparison_value . See the Julia documentation for details.

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

Convert a vector of values to a vector of Booleans, is true for (string!) entries that are not a (complete!) match to the comparison_value regular expression. See the Julia documentation for details.

class dafpy.queries. LookupMatrix ( property : str )

Lookup the value of a matrix property. See the Julia documentation for details.

class dafpy.queries. LookupScalar ( property : str )

Lookup the value of a scalar property. See the Julia documentation for details.

class dafpy.queries. LookupVector ( property : str )

Lookup the value of a vector property. See the Julia documentation for details.

class dafpy.queries. Names

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

class dafpy.queries. OrMask ( property : str )

Combine a mask with another, using the bitwise OR operator. See the Julia documentation for details.

class dafpy.queries. OrNegatedMask ( property : str )

Combine a mask with another, using the bitwise OR-NOT operator. 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 , LookupScalar , Names , QuerySequence ]

class dafpy.queries. QuerySequence ( jl_obj )

A sequence of QueryOperation . See the Julia documentation for details.

Query operations can be chained into a QuerySequence using the | operator in Python (instead of the |> operator in Julia).

class dafpy.queries. ReduceToColumn ( reduction : ReductionOperation )

Specify a ReductionOperation to convert each row of a grouped matrix to a single value, reducing the matrix to a single column per group. Must be preceded by GroupColumnsBy . See the Julia documentation for details.

class dafpy.queries. ReduceToRow ( reduction : ReductionOperation )

Specify a ReductionOperation to convert each column of a grouped matrix to a single value, reducing the matrix to a single row per group. Must be preceded by GroupRowsBy . See the Julia documentation for details.

class dafpy.queries. SquareColumnIs ( property : str )

Whenever extracting a vector from a square matrix, specify the axis entry that identifies the column to extract. See the Julia documentation for details.

class dafpy.queries. SquareRowIs ( property : str )

Whenever extracting a vector from a square matrix, specify the axis entry that identifies the row to extract. See the Julia documentation for details.

class dafpy.queries. XorMask ( property : str )

Combine a mask with another, using the bitwise XOR operator. See the Julia documentation for details.

class dafpy.queries. XorNegatedMask ( property : str )

Combine a mask with another, using the bitwise XOR operator. See the Julia documentation for details.

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

Parse a query (or a fragment of a query). See the Julia documentation for details.

dafpy.queries. is_axis_query ( query : str | Axis | LookupScalar | Names | QuerySequence ) → bool

Returns whether the query specifies a (possibly masked) axis. See the Julia documentation for details.

dafpy.queries. query_axis_name ( query : str | Axis | LookupScalar | Names | QuerySequence ) → bool

Return the axis name of a query. See the Julia documentation for details.

dafpy.queries. query_result_dimensions ( query : str | Axis | LookupScalar | 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.