# \#approx

**URL:** https://discourse.julialang.org/tag/approx/667.md

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## [History of \`isapprox\` in languages](https://discourse.julialang.org/t/history-of-isapprox-in-languages/119347)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 56\
**Last updated:** [September 19, 2024, 8:58pm UTC](https://discourse.julialang.org/t/history-of-isapprox-in-languages/119347 "2024-09-19T20:58:20Z")

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Does anyone know why the de-facto standard definition of isapprox intentionally fails when one of the arguments is zero? isapprox(0.0, 0.0 + 1e-10) # false isapprox(1.0, 1.0 + 1e-10) # true It is clear from the formula…

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## [How to efficiently and precisely fit a function with neural networks?](https://discourse.julialang.org/t/how-to-efficiently-and-precisely-fit-a-function-with-neural-networks/73726)

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**Author:** [@thorek1](https://discourse.julialang.org/u/thorek1)\
**Replies:** 16\
**Last updated:** [January 1, 2022, 1:50pm UTC](https://discourse.julialang.org/t/how-to-efficiently-and-precisely-fit-a-function-with-neural-networks/73726 "2022-01-01T13:50:36Z")

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Hi, I am trying (and failing in terms of precision) to use neural networks to fit stochastic optimal control problems. Since this problem has many parts and I would like to have 1e-6 precision I went back to something m…

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## [How can I redefine the operator "≈" to my desired tolerance](https://discourse.julialang.org/t/how-can-i-redefine-the-operator-to-my-desired-tolerance/60072)

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**Author:** [@Albert\_Zevelev](https://discourse.julialang.org/u/Albert_Zevelev)\
**Replies:** 7\
**Last updated:** [April 28, 2021, 1:26pm UTC](https://discourse.julialang.org/t/how-can-i-redefine-the-operator-to-my-desired-tolerance/60072 "2021-04-28T13:26:35Z")

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Currently, “The binary operator ≈ is equivalent to isapprox with the default arguments” Hence: x ≈ y is equivalent to isapprox(x,y) How can I redefine the operator w/ my own custom tolerance: such that: x ≈ y is equiv…

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## [Isapprox for array of tuples](https://discourse.julialang.org/t/isapprox-for-array-of-tuples/18527)

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**Author:** [@Andrey.Borzunov](https://discourse.julialang.org/u/Andrey.Borzunov)\
**Replies:** 2\
**Last updated:** [December 10, 2018, 5:35pm UTC](https://discourse.julialang.org/t/isapprox-for-array-of-tuples/18527 "2018-12-10T17:35:03Z")

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My aim is to approximately compare two arrays of tuples for needs of regression tests. There should be a more simple way to do isapprox(R,R2) than the following R = \[ (4.0, 75.96375653207353) (6.0,…