cube needs to come too

include/teqp/models/multifluid.hpp

@@ -75,6 +75,11 @@ class MultiFluidReducingFunction {
 private:
     Eigen::MatrixXd betaT, gammaT, betaV, gammaV, YT, Yv;
 
+    template <typename Num>
+    auto cube(Num x) {
+        return x * x * x;
+    }
+
 public:
 
     template<typename ArrayLike>

src/multifluid.cpp

@@ -5,11 +5,6 @@
 #include "json.hpp"
 #include "teqp/models/multifluid.hpp"
 
-template <typename Num>
-auto cube(Num x) {
-    return x*x*x;
-}
-
 
 auto build_multifluid_model(const std::vector<std::string>& components) {
     using namespace nlohmann;