Re: [Quantlib-users] Failed to import QuantLib library in python

[Christofer B. <bog...@gm...>]

This worked. Many thanks for this suggestion. Regards,

On Fri, Aug 14, 2020 at 1:07 PM Luigi Ballabio <lui...@gm...>
wrote:

> Christofer,
>     I suspect at this point you have broken pieces of installation lying
> around from three different Python versions and interfering with your new
> attempts.  I suggest you use virtualenv to create a clean environment and
> work in that one.  It's a good practice anyway.
>
> Whatever version of python3 you want to use, create a new work directory,
> enter it in the terminal, and run:
>
> python3 -m venv ql-env
>
> this will create a new directory ql-env with a clean Python environment
> (based on the version you used). You don't need to enter in the directory:
> stay where you are.  To activate the new environment, run:
>
> . ql-env/bin/activate
>
>
> (notice the single dot at the beginning followed by a space - that's
> actually a command).  Your shell prompt should now have a (ql-env) at the
> beginning to show that you're in the new environment.  Now, when you use
> python or pip (or python3 or pip3) you'll get the versions in the
> environment. To check, you can try:
>
> pip list
>
> which should return only pip and setuptools and no other module (because
> the new environment is clean).  Now finally try:
>
> pip install QuantLib
>
> which should hopefully work.  If it does, install into the environment the
> other modules you need.
>
> The new environment is only active in the shell you're using; any other
> shell and program using Python will still use the default one.  Also, if
> you exit the terminal and later you come back and want to work in the
> environment, you'll have to repeat the "activate" step above.
>
> Hope this helps,
>     Luigi
>
>
>
> On Thu, Aug 13, 2020 at 8:45 PM Christofer Bogaso <
> bog...@gm...> wrote:
>
>> Appears to me that installing Quantlib in Mac-Python3 is
>> frustratingly difficult and there are many breakpoints.
>>
>> I reinstalled Python and QuantLib altogether. With the new installation -
>>
>> >>> import sys
>>
>> >>> sys.path
>>
>> ['',
>> '/Library/Frameworks/Python.framework/Versions/3.6/lib/python36.zip',
>> '/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6',
>> '/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/lib-dynload',
>> '/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages',
>> '/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/setuptools-33.1.1-py3.6.egg']
>>
>> >>> import QuantLib
>>
>> Traceback (most recent call last):
>>
>>   File "<stdin>", line 1, in <module>
>>
>>   File
>> "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/QuantLib/__init__.py",
>> line 21, in <module>
>>
>>     from .QuantLib import *
>>
>>   File
>> "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/QuantLib/QuantLib.py",
>> line 13, in <module>
>>
>>     from . import _QuantLib
>>
>> ImportError: cannot import name '_QuantLib'
>>
>> And now it is failing with a new reason!!!
>>
>>
>> On Thu, Aug 13, 2020 at 11:11 PM Luigi Ballabio <lui...@gm...>
>> wrote:
>>
>>> From inside Python, try
>>>
>>> import sys
>>> print(sys.path)
>>>
>>> The list you get should include /usr/local/lib/python3.8/site-packages,
>>> where pip3 installed QuantLib.  If not, you might have some configuration
>>> to do.
>>>
>>> On Thu, Aug 13, 2020 at 7:09 PM Christofer Bogaso <
>>> bog...@gm...> wrote:
>>>
>>>> It would be better if I can load QuantLin with Python3.
>>>>
>>>> I failed to use some of the packages with Python2 (2.7.16) like
>>>> matplotlib. Thanks,
>>>>
>>>> On Thu, Aug 13, 2020 at 8:09 PM Javid Ashraff <jav...@ya...>
>>>> wrote:
>>>>
>>>>> I recall having the same problem in the past.  Try using pip install
>>>>> rather than pip3 install.
>>>>>
>>>>> Regards,
>>>>>
>>>>> Javid
>>>>>
>>>>> On Thursday, 13 August 2020, 19:15:32 GMT+8, Christofer Bogaso <
>>>>> bog...@gm...> wrote:
>>>>>
>>>>>
>>>>> Thanks.
>>>>>
>>>>> I have reinstalled Python3 using brew. And then installed again the
>>>>> QuantLib as below -
>>>>>
>>>>> pip3 install QuantLib-Python
>>>>>
>>>>> Requirement already satisfied: QuantLib-Python in
>>>>> /usr/local/lib/python3.8/site-packages (1.18)
>>>>>
>>>>> Requirement already satisfied: QuantLib in
>>>>> /usr/local/lib/python3.8/site-packages (from QuantLib-Python) (1.19)
>>>>>
>>>>> After that I tried to import the library within Python3, but failed.
>>>>>
>>>>> >>> import QuantLib as ql
>>>>>
>>>>> Traceback (most recent call last):
>>>>>
>>>>>   File "<stdin>", line 1, in <module>
>>>>>
>>>>> ModuleNotFoundError: No module named 'QuantLib'
>>>>>
>>>>> Any idea why is it failing?
>>>>>
>>>>> On Thu, Aug 13, 2020 at 4:36 PM Luigi Ballabio <
>>>>> lui...@gm...> wrote:
>>>>>
>>>>> I don't think there is.  You'll probably have to remove the *build/bdist.macosx-10.15-x86_64/egg/
>>>>> *directory.  To be sure you're not missing anything, you might also
>>>>> run "pip uninstall QuantLib-Python" first, then look for anything related
>>>>> to QuantLib in /usr/local/lib and its Python subdirectories.  Once you
>>>>> clean them (but be careful to only clean stuff with "quantlib" in its
>>>>> name), you can run "pip install" again.
>>>>>
>>>>> Luigi
>>>>>
>>>>>
>>>>> On Thu, Aug 13, 2020 at 12:00 PM Christofer Bogaso <
>>>>> bog...@gm...> wrote:
>>>>>
>>>>> Thanks Luigi. But, how can I clean that? Is there any specific syntax?
>>>>>
>>>>> On Thu, Aug 13, 2020 at 3:19 PM Luigi Ballabio <
>>>>> lui...@gm...> wrote:
>>>>>
>>>>> Hello,
>>>>>     from the fact the traceback starts from "
>>>>> *build/bdist.macosx-10.15-x86_64/egg/"* and the fact it refers to
>>>>> */usr/local/lib/libQuantLib.0.dylib,* it looks to me like it's
>>>>> importing a version you tried to compile rather than the one you installed
>>>>> with pip.  If that's the case, I'd try cleaning that one up.
>>>>>
>>>>> Hope this helps,
>>>>>     Luigi
>>>>>
>>>>>
>>>>> On Thu, Aug 13, 2020 at 11:35 AM Christofer Bogaso <
>>>>> bog...@gm...> wrote:
>>>>>
>>>>> Hi,
>>>>>
>>>>> I wanted to run QuantLib from my Python workplace, however failed to
>>>>> import the library with below error -
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> *>>> import QuantLibTraceback (most recent call last):  File
>>>>> "<stdin>", line 1, in <module>  File
>>>>> "build/bdist.macosx-10.15-x86_64/egg/QuantLib/__init__.py", line 24, in
>>>>> <module>  File "build/bdist.macosx-10.15-x86_64/egg/QuantLib/QuantLib.py",
>>>>> line 13, in <module>  File
>>>>> "build/bdist.macosx-10.15-x86_64/egg/QuantLib/_QuantLib.py", line 7, in
>>>>> <module>  File "build/bdist.macosx-10.15-x86_64/egg/QuantLib/_QuantLib.py",
>>>>> line 6, in __bootstrap__ImportError:
>>>>> dlopen(/Users/aa/Library/Caches/Python-Eggs/QuantLib_Python-1.16.1-py2.7-macosx-10.15-x86_64.egg-tmp/QuantLib/_QuantLib.so,
>>>>> 2): Symbol not found:
>>>>> __ZN8QuantLib10IborCouponC1ERKNS_4DateEdS3_S3_jRKN5boost10shared_ptrINS_9IborIndexEEEddS3_S3_RKNS_10DayCounterEb
>>>>> Referenced from:
>>>>> /Users/aa/Library/Caches/Python-Eggs/QuantLib_Python-1.16.1-py2.7-macosx-10.15-x86_64.egg-tmp/QuantLib/_QuantLib.so
>>>>> Expected in: /usr/local/lib/libQuantLib.0.dylib in
>>>>> /Users/aa/Library/Caches/Python-Eggs/QuantLib_Python-1.16.1-py2.7-macosx-10.15-x86_64.egg-tmp/QuantLib/_QuantLib.so*
>>>>>
>>>>> I used the syntax *pip install QuantLib-Python* when I installed
>>>>> QuantLib, the installation appears to be successful.
>>>>>
>>>>> Any help will be highly appreciated.
>>>>>
>>>>> Thanks,
>>>>> _______________________________________________
>>>>> QuantLib-users mailing list
>>>>> Qua...@li...
>>>>> https://lists.sourceforge.net/lists/listinfo/quantlib-users
>>>>>
>>>>> _______________________________________________
>>>>> QuantLib-users mailing list
>>>>> Qua...@li...
>>>>> https://lists.sourceforge.net/lists/listinfo/quantlib-users
>>>>>
>>>>