refactor: Moved from T to Fractions

src/lib.rs

@@ -1,41 +1,32 @@
 use core::panic;
 use fractions::Fraction;
-use num_traits::{Float, Num, NumAssign, Signed};
-use std::fmt::{self, Debug};
+use std::fmt::{Debug, Display};
 use std::ops::Add;
 use std::ops::Mul;
 use std::ops::Sub;
 
-#[derive(PartialEq, Eq, Debug)]
-pub struct Matrix<
-    T: Num
-        + NumAssign
-        + Signed
-        + Float
-        + fmt::Display
-        + Copy
-        + PartialEq
-        + Debug
-        + std::iter::Product<T>,
-> {
-    rows: usize,
-    columns: usize,
-    data: Vec<T>,
+#[derive(Debug, Eq, PartialEq)]
+pub enum MatrixError {
+    IndexOutOfRange,
+    RowOutOfRange,
+    ColumnOutOfRange,
+    NotSquared,
+    InvalidDataSize,
+    InvalidSizeForAdd,
+    InvalidSizeForSub,
+    InvalidSizeForMul,
+    ZeroSize,
 }
 
-impl<
-        T: Num
-            + NumAssign
-            + Signed
-            + Float
-            + fmt::Display
-            + Copy
-            + PartialEq
-            + Debug
-            + std::iter::Product<T>,
-    > Matrix<T>
-{
-    pub fn new(rows: usize, columns: usize, default: T) -> Self {
+#[derive(PartialEq, Eq, Debug)]
+pub struct Matrix {
+    rows: usize,
+    columns: usize,
+    data: Vec<Fraction>,
+}
+
+impl Matrix {
+    pub fn new(rows: usize, columns: usize, default: Fraction) -> Self {
         Self {
             rows,
             columns,
@@ -43,7 +34,7 @@ impl<
         }
     }
 
-    pub fn get(&self, row: usize, column: usize) -> &T {
+    pub fn get(&self, row: usize, column: usize) -> &Fraction {
         if row >= self.rows || column >= self.columns {
             panic!("Index given is out of range.")
         }
@@ -53,7 +44,7 @@ impl<
         return &self.data[index];
     }
 
-    pub fn get_row(&self, row: usize) -> Vec<T> {
+    pub fn get_row(&self, row: usize) -> Vec<Fraction> {
         if row >= self.rows {
             panic!("Row index is out of bounds.");
         }
@@ -69,7 +60,7 @@ impl<
         return data;
     }
 
-    pub fn get_column(&self, column: usize) -> Vec<T> {
+    pub fn get_column(&self, column: usize) -> Vec<Fraction> {
         if column >= self.columns {
             panic!("Column index is out of bounds.");
         }
@@ -84,14 +75,14 @@ impl<
         return data;
     }
 
-    pub fn get_diagonal(&self) -> Vec<T> {
+    pub fn get_diagonal(&self) -> Vec<Fraction> {
         if self.columns != self.rows {
             panic!("The matrix needs to be squared for getting diagonal.")
         }
 
         let mut data = Vec::new();
 
-        let mut index = 0;
+        let mut index;
         for i in 0..self.columns {
             index = i + (i * self.columns);
             data.push(self.data[index]);
@@ -99,7 +90,7 @@ impl<
         return data;
     }
 
-    pub fn set(&mut self, row: usize, column: usize, data: T) -> () {
+    pub fn set(&mut self, row: usize, column: usize, data: Fraction) -> () {
         if row >= self.rows || column >= self.columns {
             panic!("Index given is out of range.")
         }
@@ -110,7 +101,7 @@ impl<
         return;
     }
 
-    pub fn set_row(&mut self, row: usize, data: Vec<T>) -> () {
+    pub fn set_row(&mut self, row: usize, data: Vec<Fraction>) -> () {
         if row >= self.rows {
             panic!("Row index given is out of bounds.")
         }
@@ -123,7 +114,7 @@ impl<
         }
     }
 
-    pub fn set_column(&mut self, column: usize, data: Vec<T>) -> () {
+    pub fn set_column(&mut self, column: usize, data: Vec<Fraction>) -> () {
         if column >= self.columns {
             panic!("Column index given is out of bouds.")
         }
@@ -167,7 +158,7 @@ impl<
         }
     }
 
-    pub fn get_determinant(&self) -> T {
+    pub fn get_determinant(&self) -> Fraction {
         if self.rows != self.columns {
             panic!("Only nxn matrixes can have a determinant.");
         }
@@ -177,65 +168,66 @@ impl<
             rows: self.rows,
             data: self.data.clone(),
         };
-        let mut sign = T::one();
+        let mut sign = Fraction::new(1, 1).unwrap();
 
         for i in 0..self.columns {
-            let mut pivot = *trig_matrix.get(i, i);
+            let mut max_row = i;
+            let mut max_value = trig_matrix.get(i, i).abs();
 
-            // Assign x to next row
-            let mut x = i + 1;
-            while pivot.is_zero() && x < self.rows {
-                if !trig_matrix.get(x, i).is_zero() {
-                    trig_matrix.exchange_rows(x, i);
-                    sign = -sign;
-                    pivot = *trig_matrix.get(i, i);
-                    break;
+            // We do parcial pivoting to avoid getting insane
+            // numbers that may result in overflow with fractions
+            for r in (i + 1)..self.rows {
+                let val = trig_matrix.get(r, i).abs();
+                if val > max_value {
+                    max_value = val;
+                    max_row = r;
                 }
-                x += 1;
-            }
-            // If even exchanging in all ways posible pivot is still 0
-            // then determinant is 0
-            if pivot.is_zero() {
-                return T::zero();
             }
 
-            //So, we got the pivot, now we evaluate to 0 to create the
-            //triangular matrix
-            x = i + 1;
-            while x < trig_matrix.rows {
-                let m = *trig_matrix.get(x, i) / pivot;
+            // If there ain't no other thing but 0 then we're
+            // fucked, determinant is zero
+            if max_value.is_zero() {
+                return Fraction::new(0, 1).unwrap();
+            }
+
+            if max_row != i {
+                trig_matrix.exchange_rows(i, max_row);
+                sign = -sign;
+            }
+
+            let pivot = *trig_matrix.get(i, i);
+
+            // The main gaussian elimination, not even I remember how
+            // i did it in such a asimple way
+            for x in (i + 1)..trig_matrix.rows {
+                let m = (*trig_matrix.get(x, i) / pivot).unwrap();
+
                 let new_row = trig_matrix
                     .get_row(x)
                     .iter()
                     .zip(trig_matrix.get_row(i).iter())
                     .map(|(a, b)| *a - m * *b)
-                    .collect::<Vec<T>>();
+                    .collect::<Vec<Fraction>>();
+
                 trig_matrix.set_row(x, new_row);
-                x += 1;
             }
         }
 
         // YES, now we got ourselves a triangular matrix, now we just
         // take the product of the diagonal and multiply by sign, that's
         // the determinant :)
-        let determinant = sign * trig_matrix.get_diagonal().iter().copied().product::<T>();
+        let determinant = sign
+            * trig_matrix
+                .get_diagonal()
+                .iter()
+                .copied()
+                .fold(Fraction::from(1i64), |acc, x| acc * x);
 
         return determinant;
     }
 }
 
-impl<
-        T: Num
-            + NumAssign
-            + Signed
-            + Float
-            + fmt::Display
-            + Copy
-            + PartialEq
-            + Debug
-            + std::iter::Product<T>,
-    > Add for Matrix<T>
-{
+impl Add for Matrix {
     type Output = Self;
 
     fn add(self, other: Self) -> Self::Output {
@@ -256,18 +248,7 @@ impl<
     }
 }
 
-impl<
-        T: Num
-            + NumAssign
-            + Signed
-            + Float
-            + fmt::Display
-            + Copy
-            + PartialEq
-            + Debug
-            + std::iter::Product<T>,
-    > Sub for Matrix<T>
-{
+impl Sub for Matrix {
     type Output = Self;
 
     fn sub(self, other: Self) -> Self::Output {
@@ -288,18 +269,7 @@ impl<
     }
 }
 
-impl<
-        T: Num
-            + NumAssign
-            + Signed
-            + Float
-            + fmt::Display
-            + Copy
-            + PartialEq
-            + Debug
-            + std::iter::Product<T>,
-    > Mul for Matrix<T>
-{
+impl Mul for Matrix {
     type Output = Self;
 
     fn mul(self, other: Self) -> Self::Output {
@@ -307,15 +277,15 @@ impl<
             panic!("Matrix dimentions are inadecuate.");
         }
 
-        let mut new_data: Vec<T> = Vec::new();
+        let mut new_data: Vec<Fraction> = Vec::new();
         for i in 0..self.rows {
             let current_row = self.get_row(i);
 
             for k in 0..other.columns {
                 let current_column = other.get_column(k);
-                let mut new_value = T::zero();
+                let mut new_value = Fraction::new(0, 1).unwrap();
                 for (a, b) in current_row.iter().zip(current_column.iter()) {
-                    new_value += *a * *b;
+                    new_value = new_value + (*a * *b);
                 }
                 new_data.push(new_value);
             }
@@ -329,18 +299,7 @@ impl<
     }
 }
 
-impl<
-        T: Num
-            + NumAssign
-            + Signed
-            + Float
-            + fmt::Display
-            + Copy
-            + PartialEq
-            + Debug
-            + std::iter::Product<T>,
-    > fmt::Display for Matrix<T>
-{
+impl Display for Matrix {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let mut display = String::new();
         let mut index = 0;
@@ -359,411 +318,4 @@ impl<
 #[cfg(test)]
 mod tests {
     use super::*;
-
-    #[test]
-    fn sum_two_matrix_1() {
-        let mut matrix1 = Matrix::new(4, 4, 2.0);
-        let matrix2 = Matrix::new(4, 4, 3.0);
-        let result_matrix = Matrix::new(4, 4, 5.0);
-
-        matrix1 = matrix1 + matrix2;
-
-        assert_eq!(matrix1, result_matrix);
-    }
-
-    #[test]
-    fn sum_two_matrix_2() {
-        let mut matrix1 = Matrix::new(4, 4, 2.0);
-        let mut matrix2 = Matrix::new(4, 4, 0.0);
-        let mut result_matrix = Matrix::new(4, 4, 2.0);
-
-        result_matrix.set(0, 0, 9.0);
-        matrix2.set(0, 0, 7.0);
-        matrix1 = matrix1 + matrix2;
-
-        assert_eq!(matrix1, result_matrix);
-    }
-
-    #[test]
-    #[should_panic]
-    fn sum_two_matrix_3() {
-        let mut matrix1 = Matrix::new(4, 4, 2.0);
-        let matrix2 = Matrix::new(4, 5, 0.0);
-
-        matrix1 = matrix1 + matrix2;
-    }
-
-    #[test]
-    fn substract_two_matrix_1() {
-        let mut matrix1 = Matrix::new(4, 4, 2.0);
-        let matrix2 = Matrix::new(4, 4, 3.0);
-        let result_matrix = Matrix::new(4, 4, -1.0);
-
-        matrix1 = matrix1 - matrix2;
-
-        assert_eq!(matrix1, result_matrix);
-    }
-
-    #[test]
-    fn substract_two_matrix_2() {
-        let mut matrix1 = Matrix::new(4, 4, 2.0);
-        let mut matrix2 = Matrix::new(4, 4, 0.0);
-        let mut result_matrix = Matrix::new(4, 4, 2.0);
-
-        result_matrix.set(0, 0, -5.0);
-        matrix2.set(0, 0, 7.0);
-        matrix1 = matrix1 - matrix2;
-
-        assert_eq!(matrix1, result_matrix);
-    }
-
-    #[test]
-    #[should_panic]
-    fn substract_two_matrix_3() {
-        let mut matrix1 = Matrix::new(4, 4, 2.0);
-        let matrix2 = Matrix::new(4, 5, 0.0);
-
-        matrix1 = matrix1 - matrix2;
-    }
-
-    #[test]
-    fn get_row_1() {
-        let mut matrix1 = Matrix::new(3, 4, 0.0);
-        matrix1.set(0, 0, 8.0);
-        matrix1.set(0, 1, 7.0);
-        matrix1.set(0, 2, 9.0);
-        matrix1.set(0, 3, 6.0);
-
-        let data = vec![8.0, 7.0, 9.0, 6.0];
-
-        assert_eq!(matrix1.get_row(0), data);
-    }
-
-    #[test]
-    fn get_row_2() {
-        let mut matrix1 = Matrix::new(3, 4, 0.0);
-
-        matrix1.set(2, 0, 8.0);
-        matrix1.set(2, 1, 7.0);
-        matrix1.set(2, 2, 9.0);
-        matrix1.set(2, 3, 6.0);
-
-        let data = vec![8.0, 7.0, 9.0, 6.0];
-
-        assert_eq!(matrix1.get_row(2), data);
-    }
-
-    #[test]
-    #[should_panic]
-    fn get_row_3() {
-        let matrix1 = Matrix::new(3, 4, 0.0);
-
-        let _data = matrix1.get_row(4);
-    }
-
-    #[test]
-    fn get_column_1() {
-        let mut matrix1 = Matrix::new(4, 3, 0.0);
-        matrix1.set(0, 0, 8.0);
-        matrix1.set(1, 0, 7.0);
-        matrix1.set(2, 0, 9.0);
-        matrix1.set(3, 0, 6.0);
-
-        let data = vec![8.0, 7.0, 9.0, 6.0];
-
-        assert_eq!(matrix1.get_column(0), data);
-    }
-
-    #[test]
-    fn get_column_2() {
-        let mut matrix1 = Matrix::new(4, 3, 0.0);
-
-        matrix1.set(0, 2, 8.0);
-        matrix1.set(1, 2, 7.0);
-        matrix1.set(2, 2, 9.0);
-        matrix1.set(3, 2, 6.0);
-
-        let data = vec![8.0, 7.0, 9.0, 6.0];
-
-        assert_eq!(matrix1.get_column(2), data);
-    }
-
-    #[test]
-    #[should_panic]
-    fn get_column_3() {
-        let matrix1 = Matrix::new(4, 4, 0.0);
-
-        let _data = matrix1.get_column(4);
-    }
-
-    #[test]
-    fn mult_matrix_1() {
-        let mut matrix1 = Matrix::new(4, 4, 2.0);
-        let matrix2 = Matrix::new(4, 4, 2.0);
-        let result_matrix = Matrix::new(4, 4, 16.0);
-
-        matrix1 = matrix1 * matrix2;
-
-        assert_eq!(matrix1, result_matrix);
-    }
-
-    #[test]
-    fn mult_matrix_2() {
-        let mut matrix1 = Matrix::new(4, 4, 2.0);
-        let mut matrix2 = Matrix::new(4, 3, 4.0);
-        let mut result_matrix = Matrix::new(4, 3, 0.0);
-
-        matrix1.set(0, 0, 6.0);
-        matrix1.set(0, 1, 8.0);
-        matrix1.set(0, 2, 9.0);
-        matrix1.set(0, 3, 5.0);
-        matrix1.set(1, 0, 3.0);
-        matrix1.set(1, 1, 8.0);
-        matrix1.set(1, 2, 4.0);
-        matrix1.set(1, 3, 7.0);
-        matrix1.set(2, 0, 4.0);
-        matrix1.set(2, 1, 5.0);
-        matrix1.set(2, 2, 6.0);
-        matrix1.set(2, 3, 4.0);
-        matrix1.set(3, 0, 6.0);
-        matrix1.set(3, 1, 2.0);
-        matrix1.set(3, 2, 2.0);
-        matrix1.set(3, 3, 9.0);
-
-        matrix2.set(0, 0, 7.0);
-        matrix2.set(0, 1, 6.0);
-        matrix2.set(0, 2, 1.0);
-        matrix2.set(1, 0, 6.0);
-        matrix2.set(1, 1, 4.0);
-        matrix2.set(1, 2, 8.0);
-        matrix2.set(2, 0, 3.0);
-        matrix2.set(2, 1, 0.0);
-        matrix2.set(2, 2, 6.0);
-        matrix2.set(3, 0, 1.0);
-        matrix2.set(3, 1, 1.0);
-        matrix2.set(3, 2, 1.0);
-
-        result_matrix.set(0, 0, 122.0);
-        result_matrix.set(0, 1, 73.0);
-        result_matrix.set(0, 2, 129.0);
-        result_matrix.set(1, 0, 88.0);
-        result_matrix.set(1, 1, 57.0);
-        result_matrix.set(1, 2, 98.0);
-        result_matrix.set(2, 0, 80.0);
-        result_matrix.set(2, 1, 48.0);
-        result_matrix.set(2, 2, 84.0);
-        result_matrix.set(3, 0, 69.0);
-        result_matrix.set(3, 1, 53.0);
-        result_matrix.set(3, 2, 43.0);
-
-        matrix1 = matrix1 * matrix2;
-
-        assert_eq!(result_matrix, matrix1);
-    }
-
-    #[test]
-    fn exchange_rows_1() {
-        let mut matrix = Matrix::new(3, 4, 5.0);
-        matrix.set(0, 0, 1.0);
-        matrix.set(0, 1, 2.0);
-        matrix.set(0, 2, 3.0);
-        matrix.set(0, 3, 4.0);
-        matrix.set(1, 0, 5.0);
-        matrix.set(1, 1, 6.0);
-        matrix.set(1, 2, 7.0);
-        matrix.set(1, 3, 8.0);
-
-        matrix.exchange_rows(0, 1);
-
-        let row1 = vec![1.0, 2.0, 3.0, 4.0];
-        let row2 = vec![5.0, 6.0, 7.0, 8.0];
-
-        assert_eq!(row1, matrix.get_row(1));
-        assert_eq!(row2, matrix.get_row(0));
-    }
-
-    #[test]
-    fn exchange_rows_2() {
-        let mut matrix = Matrix::new(3, 4, 5.0);
-        matrix.set(0, 0, 1.0);
-        matrix.set(0, 1, 2.0);
-        matrix.set(0, 2, 3.0);
-        matrix.set(0, 3, 4.0);
-        matrix.set(2, 0, 5.0);
-        matrix.set(2, 1, 6.0);
-        matrix.set(2, 2, 7.0);
-        matrix.set(2, 3, 8.0);
-
-        matrix.exchange_rows(0, 2);
-
-        let row1 = vec![1.0, 2.0, 3.0, 4.0];
-        let row2 = vec![5.0, 6.0, 7.0, 8.0];
-
-        assert_eq!(row1, matrix.get_row(2));
-        assert_eq!(row2, matrix.get_row(0));
-    }
-
-    #[test]
-    fn exchange_columns_1() {
-        let mut matrix = Matrix::new(3, 4, 5.0);
-        matrix.set(0, 0, 1.0);
-        matrix.set(1, 0, 2.0);
-        matrix.set(2, 0, 3.0);
-        matrix.set(0, 1, 4.0);
-        matrix.set(1, 1, 5.0);
-        matrix.set(2, 1, 6.0);
-
-        matrix.exchange_columns(0, 1);
-
-        let column1 = vec![1.0, 2.0, 3.0];
-        let column2 = vec![4.0, 5.0, 6.0];
-
-        assert_eq!(column1, matrix.get_column(1));
-        assert_eq!(column2, matrix.get_column(0));
-    }
-
-    #[test]
-    fn exchange_columns_2() {
-        let mut matrix = Matrix::new(3, 4, 5.0);
-        matrix.set(0, 0, 1.0);
-        matrix.set(1, 0, 2.0);
-        matrix.set(2, 0, 3.0);
-        matrix.set(0, 3, 4.0);
-        matrix.set(1, 3, 5.0);
-        matrix.set(2, 3, 6.0);
-
-        matrix.exchange_columns(0, 3);
-
-        let column1 = vec![1.0, 2.0, 3.0];
-        let column2 = vec![4.0, 5.0, 6.0];
-
-        assert_eq!(column1, matrix.get_column(3));
-        assert_eq!(column2, matrix.get_column(0));
-    }
-
-    #[test]
-    fn set_row_1() {
-        let mut matrix = Matrix::new(3, 4, 5.0);
-        let vec1 = vec![1.0, 2.0, 3.0, 4.0];
-        matrix.set_row(0, vec1);
-
-        let vec2 = vec![1.0, 2.0, 3.0, 4.0];
-        let row = matrix.get_row(0);
-        assert_eq!(row, vec2);
-    }
-
-    #[test]
-    fn set_row_2() {
-        let mut matrix = Matrix::new(3, 4, 5.0);
-        let vec1 = vec![1.0, 2.0, 3.0, 4.0];
-        matrix.set_row(2, vec1);
-
-        let vec2 = vec![1.0, 2.0, 3.0, 4.0];
-        let row = matrix.get_row(2);
-        assert_eq!(row, vec2);
-    }
-
-    #[test]
-    fn set_column_1() {
-        let mut matrix = Matrix::new(3, 4, 5.0);
-        let vec1 = vec![1.0, 2.0, 3.0];
-        matrix.set_column(0, vec1);
-
-        let vec2 = vec![1.0, 2.0, 3.0];
-        let column = matrix.get_column(0);
-        assert_eq!(column, vec2);
-    }
-
-    #[test]
-    fn set_column_2() {
-        let mut matrix = Matrix::new(3, 4, 5.0);
-        let vec1 = vec![1.0, 2.0, 3.0];
-        matrix.set_column(3, vec1);
-
-        let vec2 = vec![1.0, 2.0, 3.0];
-        let column = matrix.get_column(3);
-        assert_eq!(column, vec2);
-    }
-
-    #[test]
-    fn get_diagonal_1() {
-        let mut matrix = Matrix::new(3, 3, 8.0);
-        matrix.set(0, 0, 1.0);
-        matrix.set(1, 1, 2.0);
-        matrix.set(2, 2, 3.0);
-
-        let vec1 = vec![1.0, 2.0, 3.0];
-        assert_eq!(matrix.get_diagonal(), vec1);
-    }
-
-    #[test]
-    fn get_diagonal_2() {
-        let mut matrix = Matrix::new(4, 4, 8.0);
-        matrix.set(0, 0, 1.0);
-        matrix.set(1, 1, 2.0);
-        matrix.set(2, 2, 3.0);
-        matrix.set(3, 3, 4.0);
-
-        let vec1 = vec![1.0, 2.0, 3.0, 4.0];
-        assert_eq!(matrix.get_diagonal(), vec1);
-    }
-
-    #[test]
-    fn get_determinant_1() {
-        let mut matrix = Matrix::new(2, 2, 0.0);
-        matrix.set(0, 0, 2.0);
-        matrix.set(1, 0, 4.0);
-        matrix.set(0, 1, 3.0);
-        matrix.set(1, 1, 5.0);
-
-        assert_eq!(matrix.get_determinant(), -2.0);
-    }
-
-    #[test]
-    fn get_determinant_2() {
-        let mut matrix = Matrix::new(3, 3, 0.0);
-        matrix.set(0, 0, 3.0);
-        matrix.set(1, 0, 4.0);
-        matrix.set(2, 0, 7.0);
-        matrix.set(0, 1, 2.0);
-        matrix.set(1, 1, 5.0);
-        matrix.set(2, 1, 8.0);
-        matrix.set(0, 2, 1.0);
-        matrix.set(1, 2, 6.0);
-        matrix.set(2, 2, 9.0);
-
-        assert_eq!(matrix.get_determinant(), 0.0);
-    }
-
-    #[test]
-    fn get_determinant_3() {
-        let mut matrix = Matrix::new(3, 3, 0.0);
-        matrix.set(0, 0, 0.0);
-        matrix.set(1, 0, 1.0);
-        matrix.set(2, 0, 2.0);
-        matrix.set(0, 1, 2.0);
-        matrix.set(1, 1, 3.0);
-        matrix.set(2, 1, 1.0);
-        matrix.set(0, 2, 1.0);
-        matrix.set(1, 2, 4.0);
-        matrix.set(2, 2, 3.0);
-
-        assert_eq!(matrix.get_determinant(), 5.0);
-    }
-
-    #[test]
-    fn get_determinant_4() {
-        let mut matrix = Matrix::new(3, 3, 0.0);
-        matrix.set(0, 0, 2.0);
-        matrix.set(1, 0, 0.0);
-        matrix.set(2, 0, 1.0);
-        matrix.set(0, 1, 3.0);
-        matrix.set(1, 1, 4.0);
-        matrix.set(2, 1, 0.0);
-        matrix.set(0, 2, 5.0);
-        matrix.set(1, 2, 1.0);
-        matrix.set(2, 2, 6.0);
-
-        assert_eq!(matrix.get_determinant(), 31.0);
-    }
 }