Chen Nuo

Question: Davidson slowed down by maintaining unneeded scc array

3

### Details It seems that `scc` array is allocated, maintained but not accessed by actual `diag_zhegvx` procedure of reduced basis set. In `diago_david.cpp`, `scc` is updated and referenced here: ```cpp...

### Describe the Code Quality Issue ### Description Original design use pointer `pdiagh` in base class `HSolver` to manage different iteration solvers. Now that we migrate to object instance of...

Confusing Interface of hPsi

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### Describe the Code Quality Issue ### Description In module `HSolver`, we need `hPsi` as a function to perform a matrix-blockvector multiplication on input `psi`. We need to perform Matrix-Vector...

### Reminder - [ ] Have you linked an issue with this pull request? - [ ] Have you added adequate unit tests and/or case tests for your pull request?...

### Background I propose the development of a new feature within our software framework: the implementation of the Locally Optimal Block Preconditioned Conjugate Gradient (LOBPCG) algorithm as a general eigenvalue...

Lack of Error Checking of base_device memory operators

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### Describe the Code Quality Issue ```cpp // namespace base_device::memory // in module_base/module_device/memory_op.cpp template struct resize_memory_op { void operator()(const base_device::DEVICE_CPU* dev, FPTYPE*& arr, const size_t size, const char* record_in) {...

Davidson Breakdown if eigenpairs converged in pre-loop cycle

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### Describe the bug ### Description Efforts are made to make eigensolver an independent module. After conducting an investigation and testing, I've encountered an issue with the `diag_once` function where...

### Describe the Code Quality Issue ### Issue Description Upon reviewing the current codebase, I've noticed that there seems to be duplicate functionality in the implementation of the `sPsi` function....

Precision Discrepancy of stress between single- and multi-core

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### Describe the bug When running `cell-relax` of a FCC-Al(See #6141 ), I discovered that stress given by CPU and GPU will diverge slightly between single- and multi-core. All parts...

### Describe the bug When running `cell-relax` of a simple FCC-Al, GPU calculation output diverges from CPU results. The **CPU** calculation converges within 3 steps, with `FINAL_ETOT_IS -1883.2252729313104282 eV`, while...