fix: minor refactoring

src/optimization/first_order/gradient_descent.rs

@@ -1,5 +1,4 @@
 use std::default::Default;
-use std::fmt::Debug;
 
 use crate::math::num::FloatExt;
 use crate::linalg::Matrix;
@@ -23,7 +22,7 @@ impl<T: FloatExt> Default for GradientDescent<T> {
      }
 }
 
-impl<T: FloatExt + Debug> FirstOrderOptimizer<T> for GradientDescent<T>
+impl<T: FloatExt> FirstOrderOptimizer<T> for GradientDescent<T>
 {
 
     fn optimize<'a, X: Matrix<T>, LS: LineSearchMethod<T>>(&self, f: &'a F<T, X>, df: &'a DF<X>, x0: &X, ls: &'a LS) -> OptimizerResult<T, X> {        

src/optimization/first_order/lbfgs.rs

@@ -35,7 +35,7 @@ impl<T: FloatExt> Default for LBFGS<T> {
      }
 }
 
-impl<T: FloatExt + Debug> LBFGS<T> {
+impl<T: FloatExt> LBFGS<T> {
 
     fn two_loops<X: Matrix<T>>(&self, state: &mut LBFGSState<T, X>) {        
 
@@ -169,7 +169,7 @@ impl<T: FloatExt + Debug> LBFGS<T> {
 }
 
 #[derive(Debug)]
-struct LBFGSState<T: FloatExt + Debug, X: Matrix<T>> {
+struct LBFGSState<T: FloatExt, X: Matrix<T>> {
     x: X,
     x_prev: X,
     x_f: T,
@@ -189,7 +189,7 @@ struct LBFGSState<T: FloatExt + Debug, X: Matrix<T>> {
     alpha: T
 }
 
-impl<T: FloatExt + Debug> FirstOrderOptimizer<T> for LBFGS<T> {
+impl<T: FloatExt> FirstOrderOptimizer<T> for LBFGS<T> {
 
     fn optimize<'a, X: Matrix<T>, LS: LineSearchMethod<T>>(&self, f: &F<T, X>, df: &'a DF<X>, x0: &X, ls: &'a LS) -> OptimizerResult<T, X> {     
         

src/optimization/first_order/mod.rs

@@ -9,12 +9,12 @@ use crate::linalg::Matrix;
 use crate::optimization::line_search::LineSearchMethod;
 use crate::optimization::{F, DF};
 
-pub trait FirstOrderOptimizer<T: FloatExt + Debug> {
+pub trait FirstOrderOptimizer<T: FloatExt> {
     fn optimize<'a, X: Matrix<T>, LS: LineSearchMethod<T>>(&self, f: &F<T, X>, df: &'a DF<X>, x0: &X, ls: &'a LS) -> OptimizerResult<T, X>;    
 }
 
 #[derive(Debug, Clone)]
-pub struct OptimizerResult<T: FloatExt + Debug, X: Matrix<T>> 
+pub struct OptimizerResult<T: FloatExt, X: Matrix<T>> 
 {
     pub x: X,
     pub f_x: T,