  We present IrRep - a Python code that calculates the symmetry eigenvalues of
electronic Bloch states in crystalline solids and the irreducible
representations under which they transform. As input it receives bandstructures
computed with state-of-the-art Density Functional Theory codes such as VASP,
Quantum Espresso, or Abinit, as well as any other code that has an interface to
Wannier90. Our code is applicable to materials in any of the 230 space groups
and double groups preserving time-reversal symmetry with or without spin-orbit
coupling included, for primitive or conventional unit cells. This makes IrRep a
powerful tool to systematically analyze the connectivity and topological
classification of bands, as well as to detect insulators with non-trivial
topology, following the Topological Quantum Chemistry formalism: IrRep can
generate the input files needed to calculate the (physical) elementary band
representations and the symmetry-based indicators using the CheckTopologicalMat
routine of the Bilbao Crystallographic Server. It is also particularly suitable
for interfaces with other plane-waves based codes, due to its flexible
structure.
