Code Examples

Below are code examples for common tasks that come up when using ITensor. Please email us to suggest a formula you would like to see, or contribute one by submitting a pull request to our website Github repo.

ITensor Examples

• Print the indices of an ITensor
• Write and Read an ITensor to Disk with HDF5

MPS and MPO Examples

Examples involving matrix product states (MPS), matrix product operators (MPO), and algorithms such as DMRG.

MPS Basics

• Apply a one-site operator to an MPS
• Apply a two-site operator to an MPS
• Measure local properties of an MPS
• Compute the entanglement entropy of an MPS
• Write and Read an MPS or MPO to Disk with HDF5

DMRG Examples

• Perform a basic DMRG calculation
• DMRG calculation with mixed local Hilbert spaces
• Make a 2D Hamiltonian for DMRG
• Compute excited states with DMRG

Physics Examples

Examples involving physics-specific features of ITensor.

• Custom local Hilbert space
• Custom local Hilbert space with QNs
• Extending existing Hilbert space definitions