Precision for operations in CKKS about seal-python HOT 7 CLOSED

@Mishra1992 disable it by passing -DSEAL_THROW_ON_TRANSPARENT_CIPHERTEXT=OFF when configuring SEAL through CMake, or evaluate in pure ciphertext.

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It depends on: parms.set_coeff_modulus(CoeffModulus.Create(poly_modulus_degree, [60, 40, 40, 60])). If poly_modulus_degree higher, the CoeffModulus.MaxBitCount(poly_modulus_degree) will be bigger, but the sum of [60, 40, 40, 60] should be the same or smaller than the MaxBitCount, and the size of keys and ciphers will be bigger and the delay will be higher.

In summary:
the precision of number <- CoeffModulus(like 60, 40, 30...) <- poly_modulus_degree
precision <-> speed and keys' size

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So, if I want to use constants of order 1e-5(without getting error), what kind of parameters should I use? Could you suggest some?

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I guess scale determines the amount of precision(1/scale of precision). If you use scale = 2^10, you could use numbers of order 1e-3 where as if you use scale = 2^40, you could use numbers of the order 1e-13.

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Hi @Huelse,
I tried to run https://github.com/Huelse/SEAL-Python/blob/main/examples/matrix_operations.py file after some minor changes and I am getting same error :
evaluator.multiply_plain(temp_rot, plain_diags[0], temp)
RuntimeError: result ciphertext is transparent.
matrix_operation.txt

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@Mishra1992 For security, the SEAL does not support pure zero vector, refer to is_transparent().

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Thank you so much for quick response @Huelse.

1. Is there any way to disable it ?
2. Since you have already added 0.00000001 so it is not pure zero vector but still getting transparent ciphertext error.
3. Any suggestion to resolve this issue.

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