forked from StrafesNET/strafe-client
34 lines
1.1 KiB
Rust
34 lines
1.1 KiB
Rust
//find roots of polynomials
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use crate::integer::Planar64;
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#[inline]
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pub fn zeroes2(a0:Planar64,a1:Planar64,a2:Planar64) -> Vec<Planar64>{
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if a2==Planar64::ZERO{
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return zeroes1(a0, a1);
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}
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let radicand=a1.get() as i128*a1.get() as i128-a2.get() as i128*a0.get() as i128*4;
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if 0<radicand {
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//start with f64 sqrt
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let planar_radicand=Planar64::raw(unsafe{(radicand as f64).sqrt().to_int_unchecked()});
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//TODO: one or two newtons
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//sort roots ascending and avoid taking the difference of large numbers
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match (Planar64::ZERO<a2,Planar64::ZERO<a1){
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(true, true )=>vec![(-a1-planar_radicand)/(a2*2),(a0*2)/(-a1-planar_radicand)],
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(true, false)=>vec![(a0*2)/(-a1+planar_radicand),(-a1+planar_radicand)/(a2*2)],
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(false,true )=>vec![(a0*2)/(-a1-planar_radicand),(-a1-planar_radicand)/(a2*2)],
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(false,false)=>vec![(-a1+planar_radicand)/(a2*2),(a0*2)/(-a1+planar_radicand)],
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}
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} else if radicand==0 {
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return vec![a1/(a2*-2)];
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} else {
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return vec![];
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}
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}
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#[inline]
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pub fn zeroes1(a0:Planar64,a1:Planar64) -> Vec<Planar64> {
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if a1==Planar64::ZERO{
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return vec![];
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} else {
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return vec![-a0/a1];
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}
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} |