ActsTrk::GbtsConnectionTable Namespace Reference

Classes
struct	Connection
	One row of the table: the two layers it connects, and the stage it is in. More...
struct	ReadResult
	The table as it is on file. More...

Functions
ReadResult	read (std::istream &inputStream)
	Read the GBTS layer connection table.

Function Documentation

read()

GbtsConnectionTable::ReadResult ActsTrk::GbtsConnectionTable::read

(

std::istream &

inputStream

)

Read the GBTS layer connection table.

The whole table, as written: which of it applies to the detector and to the pass at hand is the caller's to decide. The bin table each connection carries is skipped, GBTS recomputes it from the layer geometry.

Parameters

inputStream

the table

Exceptions

std::runtime_error

if the table cannot be read

Returns

the table

Definition at line 13 of file GbtsConnectionTableReader.cxx.

                             {
  ReadResult result;
 
  std::uint32_t nConnections{};
  std::uint32_t iConnection{};
 
  const auto fail = [&nConnections, &iConnection](const std::string& what) {
    throw std::runtime_error("GBTS connection table: cannot read " + what +
                             " at connection " + std::to_string(iConnection) +
                             " of " + std::to_string(nConnections));
  };
 
  if (!(inputStream >> nConnections >> result.etaBinWidth)) {
    throw std::runtime_error(
        "GBTS connection table: cannot read the connection count and the eta "
        "bin width");
  }
 
  for (; iConnection < nConnections; ++iConnection) {
    std::uint32_t index{};
    std::uint32_t height{};
    std::uint32_t width{};
    std::uint32_t nEntries{};
    Connection connection;
 
    if (!(inputStream >> index >> connection.stage >> connection.src >>
          connection.dst >> height >> width >> nEntries)) {
      fail("the header");
    }
 
    // GBTS recomputes the bin table from the layer geometry
    const std::uint64_t nBins = std::uint64_t{height} * width;
    for (std::uint64_t bin = 0; bin < nBins; ++bin) {
      std::uint32_t unused{};
      if (!(inputStream >> unused)) {
        fail("the bin table");
      }
    }
 
    result.connections.push_back(connection);
  }
 
  return result;
}