Wrong result for TwoCenterIntegrator module in pyabacus. #6376
Description
Describe the bug
When using ModuleNAO.TwoCenterIntegrator() module in pyabacus and calculate the overlap of two orbitals, the result mismatch the output in ABACUS. Take "Si_gga_7au_100Ry_2s2p1d.orb" for example, when I calculate the overlap of s orbital with all orbitals as follows:
from pyabacus import ModuleBase as base
from pyabacus import ModuleNAO as nao
orb = nao.RadialCollection()
orb.build(1, ["Si_gga_7au_100Ry_2s2p1d.orb"])
orb.set_uniform_grid(True, nr, cutoff, 'i', True) # nr =701, cutoff = 14.0 here
integrator = nao.TwoCenterIntegrator()
integrator.tabulate(orb, orb, 'S', nr, cutoff)
test = integrator.snap(0, 0, 0, 0, 0, dist, False) # here dist = 0 for overlap with itself
print(test[0])
The result shows
[1.111111111111111, -2.636779683484747e-16, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
However, it should be 1 at first value (itself) and 0 at other values (overlap with other s,p,d orbitals)
In ABACUS, the result is reasonable (shown below).
[1, -3.12882700630797e-16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
So there must be something wrong with this module in pyabacus.
Expected behavior
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To Reproduce
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Environment
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Additional Context
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