1 | initial version |

When you use `random()`

and `CC`

, you deal with approximate floating-point numbers. Since the fact of being positive semidefinite is sensitive to small perturbation, you will not get unreliable result, this is why the field should be exact (i.e. not made of approximate numbers). Since you use exponentials, it is not clear how to deal in an exact ring provided by Sage (such as algebraic numbers).

That said, it seems that working with `CDF`

instead of `CC`

(the former uses algorithms provided by `numpy/scipy`

which are supposed to be numerically more stable than the ones for `CC`

which are usually quite naive) answers something, but you should be careful with interpreting the result.

2 | No.2 Revision |

When you use `random()`

and `CC`

, you deal with approximate floating-point numbers. Since the fact of being positive semidefinite is sensitive to small perturbation, you will not get ~~unreliable ~~nreliable result, this is why the field should be exact (i.e. not made of approximate numbers). Since you use exponentials, it is not clear how to deal in an exact ring provided by Sage (such as algebraic numbers).

That said, it seems that working with `CDF`

instead of `CC`

(the former uses algorithms provided by `numpy/scipy`

which are supposed to be numerically more stable than the ones for `CC`

which are usually quite naive) answers something, but you should be careful with interpreting the result.

3 | No.3 Revision |

When you use `random()`

and `CC`

, you deal with approximate floating-point numbers. Since the fact of being positive semidefinite is sensitive to small perturbation, you will not get ~~nreliable ~~reliable result, this is why the field should be exact (i.e. not made of approximate numbers). Since you use exponentials, it is not clear how to deal in an exact ring provided by Sage (such as algebraic numbers).

That said, it seems that working with `CDF`

instead of `CC`

(the former uses algorithms provided by `numpy/scipy`

which are supposed to be numerically more stable than the ones for `CC`

which are usually quite naive) answers something, but you should be careful with interpreting the result.

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