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How to convert a Django QuerySet to a list
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You could do this:
import itertools
ids = set(existing_answer.answer.id for existing_answer in existing_question_answers)
answers = itertools.ifilter(lambda x: x.id not in ids, answers)
Read when QuerySets are evaluated and note that it is not good to load the whole result int...
Representing Directory & File Structure in Markdown Syntax [closed]
...se ASCII to build the structures, so your example structure becomes
.
+-- _config.yml
+-- _drafts
| +-- begin-with-the-crazy-ideas.textile
| +-- on-simplicity-in-technology.markdown
+-- _includes
| +-- footer.html
| +-- header.html
+-- _layouts
| +-- default.html
| +-- post.html
+-- _po...
How can I get rid of an “unused variable” warning in Xcode?
...as an "unused" attribute you can use to suppress that warning:
BOOL saved __attribute__((unused)) = [moc save:&error];
Alternatively (in case LLVM doesn't support the above), you could split the variable declaration into a separate line, guaranteeing that the variable would be "used" whether ...
What is the difference between sigaction and signal?
...turns.
The signal() function (usually) resets the signal action back to SIG_DFL (default) for almost all signals. This means that the signal() handler must reinstall itself as its first action. It also opens up a window of vulnerability between the time when the signal is detected and the handler ...
importing pyspark in python shell
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If it prints such error:
ImportError: No module named py4j.java_gateway
Please add $SPARK_HOME/python/build to PYTHONPATH:
export SPARK_HOME=/Users/pzhang/apps/spark-1.1.0-bin-hadoop2.4
export PYTHONPATH=$SPARK_HOME/python:$SPARK_HOME/python/build:$PYTHONPATH
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ADB No Devices Found
...s under C:\Users\<userid>\AppData\Local\Android\sdk\extras\google\usb_driver. Note that AppData is a hidden directory. I also had to confirm that I really want to install this driver although Windows claimed it wasn't compatible. But it works. Phew, quite bizarre process...
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Accessing nested JavaScript objects and arays by string path
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great stuff; using the lodash library, one can also do: _.get(object, nestedPropertyString);
– ian
Aug 13 '15 at 12:49
17
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Multi-line regex support in Vim
...t of other differences between Vim and Perl regexes.
Instead you can use \_., which means "match any single character including newline". It's a bit shorter than what you have. See :h /\_..
/This\_.*text/
share
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ImportError: numpy.core.multiarray failed to import
... following command in my Mac terminal:
python -c "import numpy;print(numpy.__version__);print(numpy.__file__)";
This command gave me the version and location of numpy that I was using (turned out it was 1.6.2). I went to this location and manually replaced it with the numpy folder for 1.8, which re...
Where is SQL Server Management Studio 2012?
... work, so I did the following and it did: 1. Found the SQLManagementStudio_x86_ENU.exe for 2008 and ran it via the command prompt like so: SQLManagementStudio_x86_ENU.exe /action=uninstall /features=Tools 2. Did the same thing to uninstall 2012 3. Restarted my computer 3. Reinstalled SSMS 2012 u...