def project_using_projection_matrix(data_to_transform, projection_matrix):
    """
    Projects given data into lower dimentional subspace using the provided
    projection_matrix.
    WARNING: the data is supposed to be in standard data science notation:
    rows: datapoints/individuals
    columns: variables/features
    """
    projected_data = projection_matrix * data_to_transform.T;
    return projected_data.T