Skip to content
Flojoy Docs

VECTOR_SUBSET

Download Flojoy Studio to try this app
The VECTOR_SUBSET node returns the subset of values from requested indices Inputs ------ v : Vector The input vector to return subset of values from Params: indices : Array specified indices to extract values at from the input vector length : int number of elements to extract from the input vector, default is 1 (this only applies when one index is specified for indices parameter) Returns: out : Vector The new vector with subset of elements extracted from the input vector
Python Code
from numpy import any, array, arange, take
from flojoy import flojoy, Vector, Array


@flojoy
def VECTOR_SUBSET(default: Vector, indices: Array, length: int = 1) -> Vector:
    """The VECTOR_SUBSET node returns the subset of values from requested indices
    Inputs
    ------
    v : Vector
        The input vector to return subset of values from

    Parameters
    ----------
    indices: Array
        specified indices to extract values at from the input vector

    length: int
        number of elements to extract from the input vector, default is 1 (this only applies when one index is specified for indices parameter)

    Returns
    -------
    Vector
        The new vector with subset of elements extracted from the input vector
    """

    # unwrap the indices first
    indices = array(indices.unwrap(), dtype=int)

    assert len(default.v) > len(
        indices
    ), "The length of indices parameter must be less than the length of the Vector."
    assert any(indices >= 0), "The indices must be greater than zero."

    if len(indices) == 1:
        assert (
            (indices[0] + (length - 1)) < len(default.v)
        ), "The length of items to delete starting from index parameter must not exceed the length of the Vector."

    if len(indices) > 1:
        v = take(default.v, indices)
    else:
        indices = arange(indices[0], length)
        v = take(default.v, indices)
    return Vector(v=v)

Find this Flojoy Block on GitHub

Example App

Having problems with this example app? Join our Discord community and we will help you out!
React Flow mini map

In this example, we generate a vector by using a LINSPACE node. Then the values located at indices 3, 1, 9 are extracted using VECTOR_SUBSET. The resulting vector is visualized with SCATTER node.