Add nantoval function.

src/Function1D.cpp

@@ -629,4 +629,7 @@ Matrix Aurora::reshape(const Matrix& aMatrix, int aRows, int aColumns, int aSlic
     }
     return Matrix::copyFromRawData(aMatrix.getData(),aRows,aColumns,aSlices);
 }
-
+void Aurora::nantoval(Matrix& aMatrix, double val2) {
+    Eigen::Map<Eigen::VectorXd> srcV(aMatrix.getData(),aMatrix.getDataSize());
+    srcV = srcV.array().isNaN().select(val2,srcV);
+}