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Type ?? for a list of help topics. > exp(Pi*I); -1 > -----Original Message----- From: Friam <[email protected]> On Behalf Of u?l? ??? Sent: Tuesday, March 9, 2021 12:55 PM To: FriAM <[email protected]> Subject: [FRIAM] Euler's Identity in 3 So, I'm trying to learn Rust. And in thinking about the ontological status of mathematical representations of waves (https://arxiv.org/abs/2101.10873), I figured I'd validate Euler's identity: fn main() { let e = num::complex::Complex::new(std::f32::consts::E,0.); let e2ip = e.powc(num::complex::Complex::new(0.,std::f32::consts::PI)); let i = num::complex::Complex::new(0.,1.); println!("ln(e^iπ) = {}",e2ip.ln()); println!("ln(-1) = {}", i.powi(2).ln()); } $ cargo run ln(e^iπ) = 0+3.1415925i ln(-1) = 0+3.141592653589793i I don't have any idea if that's a reasonable way to do that, since I'm ignorant of Rust. But it's interesting to contrast it with R and Sage: $ Rscript -e "log(exp(1)^((0+1i)*pi));log((0+1i)^2)" [1] 0+3.141593i [1] 0+3.141593i sage: numerical_approx(ln(e^(i*pi)));numerical_approx(ln(i^2)) 3.14159265358979*I 3.14159265358979*I The precision difference between the 2 results in Rust is interesting. It's the same if I use powf() instead of powi(). Any clues? Or should I simply RTFM? -- ↙↙↙ uǝlƃ - .... . -..-. . -. -.. -..-. .. ... -..-. .... . .-. . FRIAM Applied Complexity Group listserv Zoom Fridays 9:30a-12p Mtn GMT-6 bit.ly/virtualfriam un/subscribe http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM-COMIC http://friam-comic.blogspot.com/ archives: http://friam.471366.n2.nabble.com/ - .... . -..-. . -. -.. -..-. .. ... -..-. .... . .-. . FRIAM Applied Complexity Group listserv Zoom Fridays 9:30a-12p Mtn GMT-6 bit.ly/virtualfriam un/subscribe http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM-COMIC http://friam-comic.blogspot.com/ archives: http://friam.471366.n2.nabble.com/
