find_true_position

sionna.phy.utils.find_true_position(bool_tensor: torch.Tensor, side: str = 'last', axis: int = -1) → torch.Tensor

Finds the index of the first or last True value along the specified axis.

When no True value is present, it returns -1.

Parameters:

• bool_tensor (torch.Tensor) – Boolean tensor of any shape

• side (str) – 'first' | 'last'. If 'first', the first True position is found, else the last.

• axis (int) – Axis along which to find the last True value

Outputs:

position – Tensor of indices, containing the index of the first or last True value. Its shape is bool_tensor.shape with specified axis removed.

Examples

import torch
from sionna.phy.utils import find_true_position

x = torch.tensor([True, False, True, False, True])

print(find_true_position(x, side='first').item())
# 0

print(find_true_position(x, side='last').item())
# 4