Classes¶
LinearOperator¶
-
class
talon.core.LinearOperator(generators, indices_of_generators, weights)[source]¶ -
__init__(generators, indices_of_generators, weights)[source]¶ Linear operator that maps tractography to signal space. The linear operator can be used to compute products with a vector.
- Parameters
generators – np.array where each row is a generator.
indices_of_generators – COO sparse matrix that tells which generator is called where in the linear operator.
weights – COO sparse matrix that encodes the weight applied to each generator indexed by indices_of_generators. It has the same dimension as indices_of_generators.
- Raises
TypeError – If generators is not a numpy ndarray of float.
TypeError – If indices_of_generators is not a COO scipy matrix.
TypeError – If weights is not a COO scipy matrix of float64.
ValueError – If weights does not have the same dimension as indices_of_generators.
ValueError – If weights and indices_of_generators don’t have the same sparsity pattern.
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property
columns¶ Returns the indices of the nonzero columns.
- Type
int
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property
generator_length¶ length of each generator (constant across generators).
- Type
int
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property
generators¶ Returns the generators of the linear operator.
- Type
np.ndarray
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property
indices¶ Returns the generator indices.
- Type
np.ndarray
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property
nb_atoms¶ Number of atoms (columns) in the linear operator.
- Type
int
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property
nb_data¶ Number of data points.
- Type
int
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property
nb_generators¶ Number of generators.
- Type
int
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property
rows¶ Returns the indices of the nonzero rows.
- Type
int
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property
shape¶ Shape of the linear operator.
The shape is given by the number of rows and columns of the linear operator. The number of rows is equal to the number of data points times the length of the generators. The number of columns is equal to the number of atoms.
- Type
tuple of int
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todense()[source]¶ Return the dense matrix associated to the linear operator.
Note
The output of this method can be very memory heavy to store. Use at your own risk.
- Returns
full matrix representing the linear operator.
- Return type
ndarray
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property
transpose¶ the transpose of the linear operator.
- Type
TransposedLinearOperator
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property
weights¶ The weights of the nonzero elements
- Type
np.ndarray
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ConcatenatedLinearOperator¶
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class
talon.core.ConcatenatedLinearOperator(operators, axis)[source]¶ -
__init__(operators, axis)[source]¶ Concatenated LinearOperator object
The ConcatenatedLinearOperator class implements the vertical or horizontal concatenation of LinearOperator objects. It is endowed with the multiplication operation (@).
- Parameters
operators – list or tuple of LinearOperator objects to be concatenated in the same axis.
axis – int direction in which we want to concatenate the LinearOperator or ConcatenatedLinearOperator objects that we want to concatenate. Vertical concatenation is obtained for axis = 0 and horizontal concatenation is obtained for axis = 1 as in np.concatenate. (Default: 0)
- Raises
TypeError – If any element of operator is not an instance of LinearOperator or ConcatenatedLinearOperator.
TypeError – If operators is not a list or a tuple.
ValueError – If axis is not 0 or 1.
ValueError – If operators is an empty list or tuple.
ValueError – If the operators do not have compatible dimensions.
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property
axis¶ axis in which the concatenation was performed.
- Type
int
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property
operators¶ list of concatenated operators.
- Type
list
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property
shape¶ Shape of the concatenated linear operator.
- Type
tuple of int
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todense()[source]¶ Return the dense matrix associated to the linear operator.
Note
The output of this method can be very memory heavy to store. Use at your own risk.
- Returns
full matrix representing the linear operator.
- Return type
ndarray
-
property
transpose¶ transpose of the linear operator.
- Type
TransposedConcatenatedLinearOperator
-