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asked by (170 points)


I am new to c++ and itensor. When I try to do some svd with tensor version, I get a link error from the compiler as:

Undefined symbols for architecture x8664:
"itensor::svd(itensor::ITensor const&, itensor::ITensor&, itensor::ITensor&, itensor::ITensor&, itensor::Args)", referenced from:
_main in myappname.o
ld: symbol(s) not found for architecture x86
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [myappname] Error 1

But it works well with itensor version 2. Can anyone help me solve this error?

1 Answer

0 votes
answered by (70.1k points)
selected by
Best answer

Hi, thanks for reporting this issue. However, I was not able to reproduce it unfortunately. Could you please post some minimal code that you were trying to compile that led to getting this message? (So like the contents of myappname.cc?) Thanks!


commented by (170 points)
#include "itensor/all.h"
#include "myclass.h"

using namespace itensor;

        auto i = Index(2);
        auto j = Index(2);

        auto T = randomTensor(i,j);
        ITensor U(i),D,V;


        return 0;

This is the code I tried. Thanks for your response.
commented by (70.1k points)
Hi, thanks, however I do not get the error you get with that code.
Could you please try:
1. change "randomTensor" to "randomITensor" (we have deprecated randomTensor).
2. do a "make clean" and then "make" to fully recompile the ITensor library
3. then recompile your code
and see if that helps?
commented by (170 points)
I solved the error by "make clean" and "make".

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