# Zero

```#include <popops/Zero.hpp>
```

Set elements of tensor to zero.

namespace popops

Common functions, such as elementwise and reductions.

Functions

void zero(poplar::Graph &graph, poplar::Tensor t, const std::vector<poplar::Interval> &tileRegions, unsigned tile, poplar::ComputeSet zeroCS)

Append vertices to compute set `zeroCS` which zeroes elements in `tileRegions` of tensor `t` which reside on `tile`.

Parameters
• graph – The graph that the operation will be added to.

• t – The tensor whose elements are to be set to zero.

• tileRegions – The region mapping of the tensor on `tile`.

• tile – The tile which the regions relate to.

• zeroCS – The compute set to add the operation to.

void zero(poplar::Graph &graph, const poplar::Tensor &t, unsigned tile, poplar::ComputeSet zeroCS)

Append vertices to compute set `zeroCS` which zeroes all elements of tensor `t` which reside on `tile`.

Parameters
• graph – The graph that the operation will be added to.

• t – The tensor whose elements are to be set to zero.

• tile – The tile which the tensor is mapped to.

• zeroCS – The compute set to add the operation to.

void zero(poplar::Graph &graph, const poplar::Tensor &t, const std::vector<std::vector<poplar::Interval>> &mapping, poplar::ComputeSet zeroCS)

Append vertices to compute set `zeroCS` which zeroes elements in `mapping` of tensor `t` which reside on tiles represented with `mapping`.

Parameters
• graph – The graph that the operation will be added to.

• t – The tensor whose elements are to be set to zero.

• mapping – The tensor’s region mapping per tile. Each element describes a region mapping of a tile (ordered). For example, mapping[0] is tile 0’s region mapping for tensor `t`.

• zeroCS – The compute set to add the operation to.

void zero(poplar::Graph &graph, const poplar::Tensor &t, poplar::program::Sequence &prog, const poplar::DebugContext &debugContext = {})

Append programs to program sequence `prog` which zeroes all elements of tensor `t`.

Parameters
• graph – The graph that the operation will be added to.

• t – The tensor whose elements are to be set to zero.

• prog – The Poplar program sequence to append the operation to.

• debugContext – Optional debug information.