diff --git a/sophus/so2.cpp b/sophus/so2.cpp
index 44fc4a1a9..fbd237552 100644
--- a/sophus/so2.cpp
+++ b/sophus/so2.cpp
@@ -29,8 +29,7 @@ namespace Sophus
 
 SO2::SO2()
 {
-  unit_complex_.real() = 1.;
-  unit_complex_.imag() = 0.;
+  unit_complex_ = std::complex<double>(1.0, 0.0);
 }
 
 SO2