Sync public subset from Flux

include/numerics/matargmax.h

@@ -0,0 +1,62 @@
+#pragma once
+
+#include "./utils/matrix.h"
+
+namespace numerics{
+	
+	template <typename Ti, typename Td>
+	void inplace_matargmax_row(const utils::Matrix<Td>& A, utils::Vector<Ti>& b){
+
+		if (b.size() != A.rows()){
+			b.resize(A.rows(), Ti{0});
+		}
+		Td value;
+		
+		for (uint64_t i = 0; i < A.rows(); ++i){
+			value = Td{0};
+			for (uint64_t j = 0; j < A.cols(); ++j){
+				if (value < A(i,j)){
+					value = A(i,j);
+					b[i] = j;
+				}
+			}
+		}
+	}
+
+	template <typename Ti, typename Td>
+	void inplace_matargmax_col(const utils::Matrix<Td>& A, utils::Vector<Ti>& b){
+
+		if (b.size() != A.cols()){
+			b(A.cols(), Ti{0});
+		}
+		Td value;
+		
+		for (uint64_t j = 0; j < A.cols(); ++j){
+			value = Td{0};
+			for (uint64_t i = 0; i < A.cols(); ++i){
+				if (value < A(i,j)){
+					value = A(i,j);
+					b[j] = i;
+				}
+			}
+		}
+	}
+
+	template <typename Ti, typename Td>
+	utils::Vector<Ti> matargmax_row(const utils::Matrix<Td>& A){
+		utils::Vector<Ti> b(A.rows(), Ti{0});
+		inplace_matargmax_row(A, b);
+		return b;
+
+	}
+
+	template <typename Ti, typename Td>
+	utils::Vector<Ti> matargmax_col(const utils::Matrix<Td>& A){
+		utils::Vector<Ti> b(A.rows(), Ti{0});
+		inplace_matargmax_col(A, b);
+		return b;
+
+	}
+
+} // namespace numerics
+