BaseExpr¶

Public API¶

class modin.experimental.engines.omnisci_on_native.frame.expr.BaseExpr¶

An abstract base class for expression tree node.

An expression tree is used to describe how a single column of a dataframe is computed.

Each node can belong to multiple trees and therefore should be immutable until proven to have no parent nodes (e.g. by making a copy).

operands¶

Holds child nodes. Leaf nodes shouldn’t have operands attribute.

Type: list of BaseExpr, optional

add(other)¶

Build an add expression.

Parameters: other (BaseExpr) – The second operand.
Returns: The resulting add expression.
Return type: BaseExpr

bin_op(other, op_name)¶

Build a binary operation expression.

Parameters

other (BaseExpr) – The second operand.
op_name (str) – A binary operation name.

Returns

The resulting binary operation expression.

Return type

BaseExpr

cast(res_type)¶

Build a cast expression.

Parameters: res_type (dtype) – A data type to cast to.
Returns: The cast expression.
Return type: BaseExpr

collect_frames(frames)¶

Recursively collect all frames participating in the expression.

Collected frames are put into the frames set. Default implementation collects frames from the operands of the expression. Derived classes directly holding frames should provide their own implementations.

Parameters: frames (set) – Output set of collected frames.

abstract copy()¶

Make a shallow copy of the expression.

Returns
Return type: BaseExpr

eq(other)¶

Build an equality comparison of self with other.

Parameters: other (BaseExpr or scalar) – An operand to compare with.
Returns: The resulting comparison expression.
Return type: BaseExpr

floor()¶

Build a floor expression.

Returns: The resulting floor expression.
Return type: BaseExpr

floordiv(other)¶

Build a floordiv expression.

The result always has an integer data type.

Parameters: other (BaseExpr) – The second operand.
Returns: The resulting floordiv expression.
Return type: BaseExpr

is_not_null()¶

Build a NOT NULL check expression.

Returns: The NOT NULL check expression.
Return type: BaseExpr

is_null()¶

Build a NULL check expression.

Returns: The NULL check expression.
Return type: BaseExpr

le(other)¶

Build a less or equal comparison with other.

Parameters: other (BaseExpr or scalar) – An operand to compare with.
Returns: The resulting comparison expression.
Return type: BaseExpr

mod(other)¶

Build a mod expression.

Parameters: other (BaseExpr) – The second operand.
Returns: The resulting mod expression.
Return type: BaseExpr

mul(other)¶

Build a mul expression.

Parameters: other (BaseExpr) – The second operand.
Returns: The resulting mul expression.
Return type: BaseExpr

pow(other)¶

Build a power expression.

Parameters: other (BaseExpr) – The power operand.
Returns: The resulting power expression.
Return type: BaseExpr

sub(other)¶

Build a sub expression.

Parameters: other (BaseExpr) – The second operand.
Returns: The resulting sub expression.
Return type: BaseExpr

translate_input(mapper)¶

Make a deep copy of the expression translating input nodes using mapper.

The default implementation builds a copy and recursively run translation for all its operands. For leaf expressions _translate_input is called.

Parameters: mapper (InputMapper) – A mapper to use for input columns translation.
Returns: The expression copy with translated input columns.
Return type: BaseExpr

truediv(other)¶

Build a truediv expression.

The result always has float data type.

Parameters: other (BaseExpr) – The second operand.
Returns: The resulting truediv expression.
Return type: BaseExpr

InputRefExpr¶

Public API¶

class modin.experimental.engines.omnisci_on_native.frame.expr.InputRefExpr(frame, col, dtype)¶

An expression tree node to represent an input frame column.

Parameters

frame (OmnisciOnNativeFrame) – An input frame.
col (str) – An input column name.
dtype (dtype) – Input column data type.

modin_frame¶

An input frame.

Type: OmnisciOnNativeFrame

column¶

An input column name.

Type: str

_dtype¶

Input column data type.

Type: dtype

collect_frames(frames)¶

Add referenced frame to the frames set.

Parameters: frames (set) – Output set of collected frames.

copy()¶

Make a shallow copy of the expression.

Returns
Return type: InputRefExpr

LiteralExpr¶

Public API¶

class modin.experimental.engines.omnisci_on_native.frame.expr.LiteralExpr(val)¶

An expression tree node to represent a literal value.

Parameters: val (int, np.int, float, bool, str or None) – Literal value.

val¶

Literal value.

Type: int, np.int, float, bool, str or None

_dtype¶

Literal data type.

Type: dtype

copy()¶

Make a shallow copy of the expression.

Returns
Return type: LiteralExpr

OpExpr¶

Public API¶

class modin.experimental.engines.omnisci_on_native.frame.expr.OpExpr(op, operands, dtype)¶

A generic operation expression.

Used for arithmetics, comparisons, conditional operations, etc.

Parameters

op (str) – Operation name.
operands (list of BaseExpr) – Operation operands.
dtype (dtype) – Result data type.

op¶

Operation name.

Type: str

operands¶

Operation operands.

Type: list of BaseExpr

_dtype¶

Result data type.

Type: dtype

copy()¶

Make a shallow copy of the expression.

Returns
Return type: OpExpr

AggregateExpr¶

Public API¶

class modin.experimental.engines.omnisci_on_native.frame.expr.AggregateExpr(agg, op, distinct=False, dtype=None)¶

An aggregate operation expression.

Parameters

agg (str) – Aggregate name.
op (BaseExpr) – Aggregate operand.
distinct (bool, default: False) – Distinct modifier for ‘count’ aggregate.
dtype (dtype, optional) – Aggregate data type. Computed if not specified.

agg¶

Aggregate name.

Type: str

operands¶

Aggregate operands. Always has a single operand.

Type: list of BaseExpr

distinct¶

Distinct modifier for ‘count’ aggregate.

Type: bool

_dtype¶

Aggregate data type.

Type: dtype

copy()¶

Make a shallow copy of the expression.

Returns
Return type: AggregateExpr

Utilities¶

Public API¶

modin.experimental.engines.omnisci_on_native.frame.expr.is_cmp_op(op)¶

Check if operation is a comparison.

Parameters: op (str) – Operation to check.
Returns: True for comparison operations and False otherwise.
Return type: bool

modin.experimental.engines.omnisci_on_native.frame.expr.build_row_idx_filter_expr(row_idx, row_col)¶

Build an expression to filter rows by rowid.

Parameters

row_idx (int or list of int) – The row numeric indices to select.
row_col (InputRefExpr) – The rowid column reference expression.

Returns

The resulting filtering expression.

Return type

BaseExpr

modin.experimental.engines.omnisci_on_native.frame.expr.build_if_then_else(cond, then_val, else_val, res_type)¶

Build a conditional operator expression.

Parameters

cond (BaseExpr) – A condition to check.
then_val (BaseExpr) – A value to use for passed condition.
else_val (BaseExpr) – A value to use for failed condition.
res_type (dtype) – The result data type.

Returns

The conditional operator expression.

Return type

BaseExpr

modin.experimental.engines.omnisci_on_native.frame.expr.build_dt_expr(dt_operation, col_expr)¶

Build a datetime extraction expression.

Parameters

dt_operation (str) – Datetime field to extract.
col_expr (BaseExpr) – An expression to extract from.

Returns

The extract expression.

Return type

BaseExpr