Matrix¶

A Matrix is represented either by an OperationNode, or the derived class Matrix. Matrices are the most fundamental objects SystemDS operates on.

Although it is possible to generate matrices with the function calls or object construction specified below, the recommended way is to use the methods defined on SystemDSContext.

class systemds.operator.Matrix(sds_context, operation: str, unnamed_input_nodes: Union[str, Iterable[Union[DAGNode, str, int, float, bool]]] = None, named_input_nodes: Dict[str, Union[DAGNode, str, int, float, bool]] = None, local_data: numpy.array = None, brackets: bool = False)¶

__init__(sds_context, operation: str, unnamed_input_nodes: Union[str, Iterable[Union[DAGNode, str, int, float, bool]]] = None, named_input_nodes: Dict[str, Union[DAGNode, str, int, float, bool]] = None, local_data: numpy.array = None, brackets: bool = False) → Matrix¶

Create general OperationNode

Parameters

• sds_context – The SystemDS context for performing the operations

• operation – The name of the DML function to execute

• unnamed_input_nodes – inputs identified by their position, not name

• named_input_nodes – inputs with their respective parameter name

• output_type – type of the output in DML (double, matrix etc.)

• is_python_local_data – if the data is local in python e.g. Numpy arrays

• number_of_outputs – If set to other value than 1 then it is expected that this operation node returns multiple values. If set remember to set the output_types value as well.

• output_types – The types of output in a multi output scenario. Default is None, and means every multi output is a matrix.

abs() → systemds.operator.nodes.matrix.Matrix¶

Calculate absolute.

Returns

Matrix representing operation

acos() → systemds.operator.nodes.matrix.Matrix¶

Calculate arccos.

Returns

Matrix representing operation

asin() → systemds.operator.nodes.matrix.Matrix¶

Calculate arcsin.

Returns

Matrix representing operation

atan() → systemds.operator.nodes.matrix.Matrix¶

Calculate arctan.

Returns

Matrix representing operation

cbind(other) → systemds.operator.nodes.matrix.Matrix¶

Column-wise matrix concatenation, by concatenating the second matrix as additional columns to the first matrix. :param: The other matrix to bind to the right hand side. :return: The OperationNode containing the concatenated matrices/frames.

cholesky(safe: bool = False) → systemds.operator.nodes.matrix.Matrix¶

Computes the Cholesky decomposition of a symmetric, positive definite matrix

Parameters

safe – default value is False, if flag is True additional checks to ensure that the matrix is symmetric positive definite are applied, if False, checks will be skipped

Returns

the OperationNode representing this operation

code_line(var_name: str, unnamed_input_vars: Sequence[str], named_input_vars: Dict[str, str]) → str¶

Generates the DML code line equal to the intended action of this node.

Parameters

• var_name – Name of DML-variable this nodes result should be saved in

• unnamed_input_vars – all strings representing the unnamed parameters

• named_input_vars – all strings representing the named parameters (name value pairs)

Returns

the DML code line that is equal to this operation

compute(verbose: bool = False, lineage: bool = False) → numpy.array¶

Get result of this operation. Builds the dml script and executes it in SystemDS, before this method is called all operations are only building the DAG without actually executing (lazy evaluation).

Parameters

• verbose – Can be activated to print additional information such as created DML-Script

• lineage – Can be activated to print lineage trace till this node

Returns

the output as an python builtin data type or numpy array

cos() → systemds.operator.nodes.matrix.Matrix¶

Calculate cos.

Returns

Matrix representing operation

cosh() → systemds.operator.nodes.matrix.Matrix¶

Calculate cos.

Returns

Matrix representing operation

max(axis: int = None) → systemds.operator.operation_node.OperationNode¶

Calculate max of matrix.

Parameters

axis – can be 0 or 1 to do either row or column aggregation

Returns

Matrix representing operation

mean(axis: int = None) → systemds.operator.operation_node.OperationNode¶

Calculate mean of matrix.

Parameters

axis – can be 0 or 1 to do either row or column means

Returns

Matrix representing operation

min(axis: int = None) → systemds.operator.operation_node.OperationNode¶

Calculate max of matrix.

Parameters

axis – can be 0 or 1 to do either row or column aggregation

Returns

Matrix representing operation

order(by: int = 1, decreasing: bool = False, index_return: bool = False) → systemds.operator.nodes.matrix.Matrix¶

Sort by a column of the matrix X in increasing/decreasing order and returns either the index or data

Parameters

• by – sort matrix by this column number

• decreasing – If true the matrix will be sorted in decreasing order

• index_return – If true, the index numbers will be returned

Returns

the OperationNode representing this operation

pass_python_data_to_prepared_script(sds, var_name: str, prepared_script: py4j.java_gateway.JavaObject) → None¶

Passes data from python to the prepared script object.

Parameters

• jvm – the java virtual machine object

• var_name – the variable name the data should get in java

• prepared_script – the prepared script

rbind(other) → systemds.operator.nodes.matrix.Matrix¶

Row-wise matrix concatenation, by concatenating the second matrix as additional rows to the first matrix. :param: The other matrix to bind to the right hand side :return: The OperationNode containing the concatenated matrices/frames.

replace(pattern: Union[DAGNode, str, int, float, bool], replacement: Union[DAGNode, str, int, float, bool]) → Matrix¶

Replace all values with replacement value

rev() → systemds.operator.nodes.matrix.Matrix¶

Reverses the rows

Returns

the OperationNode representing this operation

round() → systemds.operator.nodes.matrix.Matrix¶

round all values to nearest natural number

Returns

The Matrix representing the result of this operation

sin() → systemds.operator.nodes.matrix.Matrix¶

Calculate sin.

Returns

Matrix representing operation

sinh() → systemds.operator.nodes.matrix.Matrix¶

Calculate sin.

Returns

Matrix representing operation

sum(axis: int = None) → systemds.operator.operation_node.OperationNode¶

Calculate sum of matrix.

Parameters

axis – can be 0 or 1 to do either row or column sums

Returns

Matrix representing operation

t() → systemds.operator.nodes.matrix.Matrix¶

Transposes the input

Returns

the OperationNode representing this operation

tan() → systemds.operator.nodes.matrix.Matrix¶

Calculate tan.

Returns

Matrix representing operation

tanh() → systemds.operator.nodes.matrix.Matrix¶

Calculate tan.

Returns

Matrix representing operation

to_one_hot(num_classes: int) → systemds.operator.nodes.matrix.Matrix¶

OneHot encode the matrix.

It is assumed that there is only one column to encode, and all values are whole numbers > 0

Parameters

num_classes – The number of classes to encode into. max value contained in the matrix must be <= num_classes

Returns

The OperationNode containing the oneHotEncoded values

to_string(**kwargs: Dict[str, Union[DAGNode, str, int, float, bool]]) → Scalar¶

Converts the input to a string representation. :return: Scalar containing the string.

var(axis: int = None) → systemds.operator.operation_node.OperationNode¶

Calculate variance of matrix.

Parameters

axis – can be 0 or 1 to do either row or column vars

Returns

Matrix representing operation