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Is it good practice to NULL a pointer after deleting it?
...pointer to 0 (which is "null" in standard C++, the NULL define from C is somewhat different) avoids crashes on double deletes.
Consider the following:
Foo* foo = 0; // Sets the pointer to 0 (C++ NULL)
delete foo; // Won't do anything
Whereas:
Foo* foo = new Foo();
delete foo; // Deletes the obj...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
... token, i.e. *.
An alternate syntax
In fact, if it is not permitted to name a field as same as its table name, RDBMS language designer could give COUNT(tableNameHere) the same semantics as COUNT(*). Example:
For counting rows we could have this:
SELECT COUNT(emp) FROM emp
And they could make i...
Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?
I've been hearing a lot about the PyPy project. They claim it is 6.3 times faster than the CPython interpreter on their site .
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What is the difference between a field and a property?
...external way they are accessed by the things that use your class." forgive me if I'm incorrectly understanding, then, but why the need for access modifiers in front of properties at all, if the field behind it seems to handle this? i.e. why make a property anything other than public?
...
Scalar vs. primitive data type - are they the same thing?
In various articles I have read, there are sometimes references to primitive data types and sometimes there are references to scalars.
...
MySQL: multiple tables or one table with many columns?
...
Any time information is one-to-one (each user has one name and password), then it's probably better to have it one table, since it reduces the number of joins the database will need to do to retrieve results. I think some databases...
Re-open *scratch* buffer in Emacs?
...e.
In general you can create as many "scratch" buffers as you want, and name them however you choose.
C-xb NAME RET
switches to a buffer NAME, creating it if it doesn't exist. A new buffer is not associated with a file on disk until you use C-xC-w (or M-x write-file RET) to choose a file wher...
Moving matplotlib legend outside of the axis makes it cutoff by the figure box
...-0.2,1.05, "Aribitrary text", transform=ax.transAxes)
ax.set_title("Trigonometry")
ax.grid('on')
fig.savefig('samplefigure', bbox_extra_artists=(lgd,text), bbox_inches='tight')
This produces:
[edit] The intent of this question was to completely avoid the use of arbitrary coordinate placements o...
What does pylint's “Too few public methods” message mean
I'm running pylint on some code, and receiving the error "Too few public methods (0/2)". What does this message mean? The pylint docs are not helpful:
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Should I test private methods or only public ones? [closed]
I have read this post about how to test private methods. I usually do not test them, because I always thought it's faster to test only public methods that will be called from outside the object. Do you test private methods? Should I always test them?
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