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Reading a huge .csv file
...tly over getdata() in your code:
for row in getdata(somefilename, sequence_of_criteria):
# process row
You now only hold one row in memory, instead of your thousands of lines per criterion.
yield makes a function a generator function, which means it won't do any work until you start looping ...
unbound method f() must be called with fibo_ instance as first argument (got classobj instance inste
...thod() to access parent methods.
class ParentClass(object):
def method_to_call(self, arg_1):
print arg_1
class ChildClass(ParentClass):
def do_thing(self):
super(ChildClass, self).method_to_call('my arg')
...
Bundling data files with PyInstaller (--onefile)
...e, so Shish's excellent answer will not work. Now the path gets set as sys._MEIPASS:
def resource_path(relative_path):
""" Get absolute path to resource, works for dev and for PyInstaller """
try:
# PyInstaller creates a temp folder and stores path in _MEIPASS
base_path = sy...
How can I handle time zones in my webapp?
...s ambiguously used. This looks like a reference: en.wikipedia.org/wiki/Tz_database From what I can tell a "timezone" is "Area/Location", e.g. "America/New_York". That appears to be geographic which is great because for instance America/Los_Angeles means BOTH PST and PDT depending on whether the ...
do N times (declarative syntax)
...s 2017, you may use ES6:
[1,2,3].forEach(i => Array(i).fill(i).forEach(_ => {
something()
}))
or in good old ES5:
[1,2,3].forEach(function(i) {
Array(i).fill(i).forEach(function() {
something()
})
}))
In both cases, the outpout will be
The outpout will be
something
somethin...
Python debugging tips [closed]
...
PDB
You can use the pdb module, insert pdb.set_trace() anywhere and it will function as a breakpoint.
>>> import pdb
>>> a="a string"
>>> pdb.set_trace()
--Return--
> <stdin>(1)<module>()->None
(Pdb) p a
'a string'
(Pdb)
To...
What's the _ underscore representative of in Swift References?
...
Both answers were correct but I want to clarify a little bit more.
_ is used to modify external parameter name behavior for methods.
In Local and External Parameter Names for Methods section of the documentation, it says:
Swift gives the first parameter name in a method a local paramete...
Check if OneToOneField is None in Django
...ately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasattr(object, 'onetoonerevrelattr') and object.onetoo...
How to update PATH variable permanently from Windows command line?
...mmatically add or modify system environment variables, add them to the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment registry key, then broadcast a WM_SETTINGCHANGE message with lParam set to the string "Environment". This allows applications, such as the shell, to ...
What is a proper naming convention for MySQL FKs?
...ue name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE TABLE messages(
message_id int,
user_id int
);
...