diff --git a/src/fourier/details/healpix_spectrum.hpp b/src/fourier/details/healpix_spectrum.hpp
index 349b88c..be69ede 100644
--- a/src/fourier/details/healpix_spectrum.hpp
+++ b/src/fourier/details/healpix_spectrum.hpp
@@ -100,8 +100,8 @@ namespace CosmoTool
         for (LType m = 1; m <= std::min(l,alms.Mmax()); m++)
           {
             std::complex<T>& c = new_data[alms.index(l,m)];
-            c.real() = gsl_ran_gaussian(rng, Al); 
-            c.imag() = gsl_ran_gaussian(rng, Al); 
+            c.real(gsl_ran_gaussian(rng, Al)); 
+            c.imag(gsl_ran_gaussian(rng, Al)); 
           }
       }
   }