topic implementing fftw3 plan for complex numbers in Intel® oneAPI Math Kernel Library https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/implementing-fftw3-plan-for-complex-numbers/m-p/771388#M630 Hi ian, <BR /><BR />Could you please provide a test case to show the problem? <BR /><BR />we can't reproduce the problem with MSVC2010, win32 console application.i modify thefile to CPP file as complex<DOUBLE> isfrom C++. and do exact as yourassignments. The below the related code, Attached is the wholecpp file. <BR /><BR />int N=131072;<BR /><BR />/* Initialize array x<N> with harmonic H */<BR />static void init(fftw_complex *x, int N, int H)<BR />{<BR /><BR /><P>std::complex<DOUBLE> *yy;<BR />yy= new std::complex<DOUBLE><N>; </N></DOUBLE></DOUBLE></P><P> for (n = 0; n &lt; N; n++)<BR /> {<BR />std::complex<DOUBLE> tmp(0.1*n, 0.5*n);<BR /> yy<N>=tmp;</N></DOUBLE></P><P> x<N>[0] = yy<N>.real(); <BR /> x<N>[1] = yy<N>.imag();<BR /><BR /><BR /> }<BR />}<BR /><BR />Regards,<BR />Ying </N></N></N></N></P></N></DOUBLE> Wed, 06 Jun 2012 03:19:49 GMT Ying_H_Intel 2012-06-06T03:19:49Z implementing fftw3 plan for complex numbers https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/implementing-fftw3-plan-for-complex-numbers/m-p/771387#M629 <P>Hi,<BR /><BR />I'm using the dp_plan_dft_1d.c type implementation from the MKL fftw3xc examples directory.<BR /><BR />However, I'm having trouble assigning a value to the fft inputs. Below is the code extract and the debug info from vs2010. </P><P>in_y<K>[0] = yy<K>.real(); </K></K></P><P>in_y<K>[1] = yy<K>.imag();</K></K></P><BR />I get<BR /><BR /><P>- in_y 0x0000000000000000 double [2]*</P><P>[0] CXX0030: Error: expression cannot be evaluated </P><P>[1] CXX0030: Error: expression cannot be evaluated </P><P>- yy [131072](0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,-0.00000000000000000,...,...) std::vector<:COMPLEX><DOUBLE>,std::allocator<:COMPLEX><DOUBLE> &gt; &gt;</DOUBLE></:COMPLEX></DOUBLE></:COMPLEX></P><P>[size] 131072 long</P><P>[capacity] 131072 long</P><P>+ [0] 0.00000000000000000 std::complex<DOUBLE></DOUBLE></P><BR /><BR />Can someone please advise where i am going wrong?<BR /><BR />Thanks Tue, 17 Apr 2012 12:08:18 GMT https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/implementing-fftw3-plan-for-complex-numbers/m-p/771387#M629 ian_bellinfantie 2012-04-17T12:08:18Z implementing fftw3 plan for complex numbers https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/implementing-fftw3-plan-for-complex-numbers/m-p/771388#M630 Hi ian, <BR /><BR />Could you please provide a test case to show the problem? <BR /><BR />we can't reproduce the problem with MSVC2010, win32 console application.i modify thefile to CPP file as complex<DOUBLE> isfrom C++. and do exact as yourassignments. The below the related code, Attached is the wholecpp file. <BR /><BR />int N=131072;<BR /><BR />/* Initialize array x<N> with harmonic H */<BR />static void init(fftw_complex *x, int N, int H)<BR />{<BR /><BR /><P>std::complex<DOUBLE> *yy;<BR />yy= new std::complex<DOUBLE><N>; </N></DOUBLE></DOUBLE></P><P> for (n = 0; n &lt; N; n++)<BR /> {<BR />std::complex<DOUBLE> tmp(0.1*n, 0.5*n);<BR /> yy<N>=tmp;</N></DOUBLE></P><P> x<N>[0] = yy<N>.real(); <BR /> x<N>[1] = yy<N>.imag();<BR /><BR /><BR /> }<BR />}<BR /><BR />Regards,<BR />Ying </N></N></N></N></P></N></DOUBLE> Wed, 06 Jun 2012 03:19:49 GMT https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/implementing-fftw3-plan-for-complex-numbers/m-p/771388#M630 Ying_H_Intel 2012-06-06T03:19:49Z