updated README

README.md

@@ -6,18 +6,17 @@ Type-safe units handling library. Do arithmetic on measurements. Convert between
 
 ```rs
 use std::f64::consts::TAU;
-
 use units::{
     dimensions::{Energy, Frequency, Length, Mass, MassMoment, Scalar},
     prefixes::Kilo,
-    units::{Grams, Joules, Meters, Number, Rpm, Watthours},
+    units::{Grams, Joules, Meters, Rpm, Watthours},
 };
 
 #[derive(Debug)]
 pub struct Flywheel {
     mass: Mass,
     radius: Length,
-    inertial_constant: Scalar,
+    inertial_constant: f64,
 }
 
 impl Flywheel {
@@ -25,22 +24,24 @@ impl Flywheel {
         Self {
             mass,
             radius,
-            inertial_constant: Scalar::new::<Number>(0.606),
+            // Cylinder
+            inertial_constant: 0.606,
         }
     }
     pub fn new_good(mass: Mass, radius: Length) -> Self {
         Self {
             mass,
             radius,
-            inertial_constant: Scalar::new::<Number>(1.0),
+            // Mass concentrated around rim
+            inertial_constant: 1.0,
         }
     }
     pub fn inertial_moment(&self) -> MassMoment {
-        self.inertial_constant * self.mass * (self.radius * self.radius)
+        self.mass * self.inertial_constant * (self.radius * self.radius)
     }
     pub fn energy(&self, spin_rate: Frequency) -> Energy {
-        let angular_velocity = spin_rate * Scalar::new::<Number>(TAU);
-        self.inertial_moment() * (angular_velocity * angular_velocity) / Scalar::new::<Number>(2.0)
+        let angular_velocity = spin_rate * TAU;
+        self.inertial_moment() * (angular_velocity * angular_velocity) / 2.0
     }
 }
 
@@ -48,7 +49,6 @@ fn main() {
     let flywheel = Flywheel::new_good(Mass::new::<Kilo<Grams>>(300.0), Length::new::<Meters>(0.5));
     let frequency = Frequency::new::<Rpm>(60000.0);
     let energy = flywheel.energy(frequency);
-    println!["Mass is in kg; Length is in meters; The inertial constant was taken from a note about moments of inertia in flywheels. A value of 1.0 means the mass is concentrated around the rim."];
     println!["{flywheel:?}"];
     println![
         "Energy at {} rpm: {} joules or {} kilowatthours",

build.rs

@@ -35,12 +35,23 @@ impl Sub for Matrix {
 
 fn impl_convert(dimension: &str) -> TokenStream {
     let dim_ident = format_ident!["{dimension}"];
-    quote! {
-        pub fn new<T: Scale<#dim_ident>>(v: f64) -> Self {
-            Self(v * T::scale().0 + T::scale().1)
+    if dimension == "Scalar" {
+        quote! {
+            pub fn new(v: f64) -> Self {
+                Self(v)
+            }
+            pub fn val(self) -> f64 {
+                self.0
+            }
         }
-        pub fn val<T: Scale<#dim_ident>>(self) -> f64 {
-            (self.0 - T::scale().1) / T::scale().0
+    } else {
+        quote! {
+            pub fn new<T: Scale<#dim_ident>>(v: f64) -> Self {
+                Self(v * T::scale().0 + T::scale().1)
+            }
+            pub fn val<T: Scale<#dim_ident>>(self) -> f64 {
+                (self.0 - T::scale().1) / T::scale().0
+            }
         }
     }
 }
@@ -186,6 +197,30 @@ fn main() {
         let decl = quote! {
             #[derive(Copy, Clone, Debug, Default)]
             pub struct #basename_ident(f64);
+            impl Mul<f64> for #basename_ident {
+                type Output = Self;
+                fn mul(self, rhs: f64) -> Self::Output {
+                    Self(self.0 * rhs)
+                }
+            }
+            impl Mul<#basename_ident> for f64 {
+                type Output = #basename_ident;
+                fn mul(self, rhs: #basename_ident) -> Self::Output {
+                    #basename_ident(self * rhs.0)
+                }
+            }
+            impl Div<f64> for #basename_ident {
+                type Output = Self;
+                fn div(self, rhs: f64) -> Self::Output {
+                    Self(self.0 / rhs)
+                }
+            }
+            impl Div<#basename_ident> for f64 {
+                type Output = #basename_ident;
+                fn div(self, rhs: #basename_ident) -> Self::Output {
+                    #basename_ident(self * rhs.0)
+                }
+            }
         };
         dims_mod.extend(decl);
         let mut conversion = quote! {};
@@ -244,38 +279,38 @@ fn main() {
 #[rustfmt::skip]
 mod matricies {
     use super::Matrix;
-    pub const Scalar:       Matrix = Matrix([ 0, 0, 0, 0, 0, 0, 0]);
-    pub const Time:         Matrix = Matrix([ 1, 0, 0, 0, 0, 0, 0]);
-    pub const Frequency:    Matrix = Matrix([-1, 0, 0, 0, 0, 0, 0]);
-    pub const Tempoflux:    Matrix = Matrix([-2, 0, 0, 0, 0, 0, 0]);
-    pub const Length:       Matrix = Matrix([ 0, 1, 0, 0, 0, 0, 0]);
-    pub const Area:         Matrix = Matrix([ 0, 2, 0, 0, 0, 0, 0]);
-    pub const Speed:        Matrix = Matrix([-1, 1, 0, 0, 0, 0, 0]);
-    pub const SquareSpeed:  Matrix = Matrix([-2, 2, 0, 0, 0, 0, 0]);
-    pub const Acceleration: Matrix = Matrix([-2, 1, 0, 0, 0, 0, 0]);
-    pub const Mass:         Matrix = Matrix([ 0, 0, 1, 0, 0, 0, 0]);
-    pub const MassPerSqTime:     Matrix = Matrix([-2, 0, 1, 0, 0, 0, 0]);
-    pub const Dispersion:   Matrix = Matrix([ 0,-2, 1, 0, 0, 0, 0]);
-    pub const Density:      Matrix = Matrix([ 0,-3, 1, 0, 0, 0, 0]);
-    pub const MassMoment:   Matrix = Matrix([ 0, 2, 1, 0, 0, 0, 0]);
-    pub const Force:        Matrix = Matrix([-2, 1, 1, 0, 0, 0, 0]);
-    pub const ForceMoment:  Matrix = Matrix([-2, 2, 1, 0, 0, 0, 0]);
-    pub const Pressure:     Matrix = Matrix([-2,-1, 1, 0, 0, 0, 0]);
-    pub const Energy:       Matrix = Matrix([-2, 2, 1, 0, 0, 0, 0]);
-    pub const Power:        Matrix = Matrix([-3, 2, 1, 0, 0, 0, 0]);
-    pub const Current:      Matrix = Matrix([ 0, 0, 0, 1, 0, 0, 0]);
-    pub const Charge:       Matrix = Matrix([ 1, 0, 0, 1, 0, 0, 0]);
-    pub const Capacitance:  Matrix = Matrix([ 4,-2,-1, 1, 0, 0, 0]);
-    pub const Potential:    Matrix = Matrix([-3,-2, 1,-1, 0, 0, 0]);
-    pub const Resistance:   Matrix = Matrix([-3, 2, 1,-2, 0, 0, 0]);
-    pub const Conductance:  Matrix = Matrix([ 3,-2,-1, 2, 0, 0, 0]);
-    pub const Flux:         Matrix = Matrix([-2, 2, 1,-1, 0, 0, 0]);
-    pub const FluxDensity:  Matrix = Matrix([ 2, 0, 1,-1, 0, 0, 0]);
-    pub const Inductance:   Matrix = Matrix([-2, 2, 1,-2, 0, 0, 0]);
-    pub const Temperature:  Matrix = Matrix([ 0, 0, 0, 0, 1, 0, 0]);
-    pub const Amount:       Matrix = Matrix([ 0, 0, 0, 0, 0, 1, 0]);
-    pub const Catalytic:    Matrix = Matrix([-1, 0, 0, 0, 0, 1, 0]);
-    pub const Intensity:    Matrix = Matrix([ 0, 0, 0, 0, 0, 0, 1]);
+    pub const Scalar:        Matrix = Matrix([ 0, 0, 0, 0, 0, 0, 0]);
+    pub const Time:          Matrix = Matrix([ 1, 0, 0, 0, 0, 0, 0]);
+    pub const Frequency:     Matrix = Matrix([-1, 0, 0, 0, 0, 0, 0]);
+    pub const Tempoflux:     Matrix = Matrix([-2, 0, 0, 0, 0, 0, 0]);
+    pub const Length:        Matrix = Matrix([ 0, 1, 0, 0, 0, 0, 0]);
+    pub const Area:          Matrix = Matrix([ 0, 2, 0, 0, 0, 0, 0]);
+    pub const Speed:         Matrix = Matrix([-1, 1, 0, 0, 0, 0, 0]);
+    pub const SquareSpeed:   Matrix = Matrix([-2, 2, 0, 0, 0, 0, 0]);
+    pub const Acceleration:  Matrix = Matrix([-2, 1, 0, 0, 0, 0, 0]);
+    pub const Mass:          Matrix = Matrix([ 0, 0, 1, 0, 0, 0, 0]);
+    pub const MassPerSqTime: Matrix = Matrix([-2, 0, 1, 0, 0, 0, 0]);
+    pub const Dispersion:    Matrix = Matrix([ 0,-2, 1, 0, 0, 0, 0]);
+    pub const Density:       Matrix = Matrix([ 0,-3, 1, 0, 0, 0, 0]);
+    pub const MassMoment:    Matrix = Matrix([ 0, 2, 1, 0, 0, 0, 0]);
+    pub const Force:         Matrix = Matrix([-2, 1, 1, 0, 0, 0, 0]);
+    pub const ForceMoment:   Matrix = Matrix([-2, 2, 1, 0, 0, 0, 0]);
+    pub const Pressure:      Matrix = Matrix([-2,-1, 1, 0, 0, 0, 0]);
+    pub const Energy:        Matrix = Matrix([-2, 2, 1, 0, 0, 0, 0]);
+    pub const Power:         Matrix = Matrix([-3, 2, 1, 0, 0, 0, 0]);
+    pub const Current:       Matrix = Matrix([ 0, 0, 0, 1, 0, 0, 0]);
+    pub const Charge:        Matrix = Matrix([ 1, 0, 0, 1, 0, 0, 0]);
+    pub const Capacitance:   Matrix = Matrix([ 4,-2,-1, 1, 0, 0, 0]);
+    pub const Potential:     Matrix = Matrix([-3,-2, 1,-1, 0, 0, 0]);
+    pub const Resistance:    Matrix = Matrix([-3, 2, 1,-2, 0, 0, 0]);
+    pub const Conductance:   Matrix = Matrix([ 3,-2,-1, 2, 0, 0, 0]);
+    pub const Flux:          Matrix = Matrix([-2, 2, 1,-1, 0, 0, 0]);
+    pub const FluxDensity:   Matrix = Matrix([ 2, 0, 1,-1, 0, 0, 0]);
+    pub const Inductance:    Matrix = Matrix([-2, 2, 1,-2, 0, 0, 0]);
+    pub const Temperature:   Matrix = Matrix([ 0, 0, 0, 0, 1, 0, 0]);
+    pub const Amount:        Matrix = Matrix([ 0, 0, 0, 0, 0, 1, 0]);
+    pub const Catalytic:     Matrix = Matrix([-1, 0, 0, 0, 0, 1, 0]);
+    pub const Intensity:     Matrix = Matrix([ 0, 0, 0, 0, 0, 0, 1]);
 }
 use matricies::*;
 
@@ -287,7 +322,7 @@ fn gen_units_list() -> HashMap<Matrix, Dimension> {
         Scalar,
         Dimension {
             basename: "Scalar",
-            conversions: vec![("Number", (1.0, 0.0))],
+            conversions: vec![],
         },
     );
     output.insert(

examples/convert.rs

@@ -4,5 +4,5 @@ use units::{
 };
 
 fn main() {
-    println!["{}", Length::new::<Meters>(2.0).val::<Feet>()];
+    println!["{}", Length::new::<Feet>(1601.0).val::<Meters>()];
 }

examples/flywheel.rs

@@ -1,16 +1,15 @@
 use std::f64::consts::TAU;
-
 use units::{
     dimensions::{Energy, Frequency, Length, Mass, MassMoment, Scalar},
     prefixes::Kilo,
-    units::{Grams, Joules, Meters, Number, Rpm, Watthours},
+    units::{Grams, Joules, Meters, Rpm, Watthours},
 };
 
 #[derive(Debug)]
 pub struct Flywheel {
     mass: Mass,
     radius: Length,
-    inertial_constant: Scalar,
+    inertial_constant: f64,
 }
 
 impl Flywheel {
@@ -18,22 +17,24 @@ impl Flywheel {
         Self {
             mass,
             radius,
-            inertial_constant: Scalar::new::<Number>(0.606),
+            // Cylinder
+            inertial_constant: 0.606,
         }
     }
     pub fn new_good(mass: Mass, radius: Length) -> Self {
         Self {
             mass,
             radius,
-            inertial_constant: Scalar::new::<Number>(1.0),
+            // Mass concentrated around rim
+            inertial_constant: 1.0,
         }
     }
     pub fn inertial_moment(&self) -> MassMoment {
-        self.inertial_constant * self.mass * (self.radius * self.radius)
+        self.mass * self.inertial_constant * (self.radius * self.radius)
     }
     pub fn energy(&self, spin_rate: Frequency) -> Energy {
-        let angular_velocity = spin_rate * Scalar::new::<Number>(TAU);
-        self.inertial_moment() * (angular_velocity * angular_velocity) / Scalar::new::<Number>(2.0)
+        let angular_velocity = spin_rate * TAU;
+        self.inertial_moment() * (angular_velocity * angular_velocity) / 2.0
     }
 }
 
@@ -41,7 +42,6 @@ fn main() {
     let flywheel = Flywheel::new_good(Mass::new::<Kilo<Grams>>(300.0), Length::new::<Meters>(0.5));
     let frequency = Frequency::new::<Rpm>(60000.0);
     let energy = flywheel.energy(frequency);
-    println!["Mass is in kg; Length is in meters; The inertial constant was taken from a note about moments of inertia in flywheels. A value of 1.0 means the mass is concentrated around the rim."];
     println!["{flywheel:?}"];
     println![
         "Energy at {} rpm: {} joules or {} kilowatthours",