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Objective-C ARC: strong vs retain and weak vs assign
...on error to use assign for an object. You have to use either weak or unsafe_unretained (which is unsafe, obviously) if you don't want to retain the property.
– cobbal
Jan 19 '12 at 15:07
...
What is the difference between shallow copy, deepcopy and normal assignment operation?
... @grc But I have tried an example(I remove the new line here.) list_=[[1,2],[3,4]] newlist = list_.copy() list_[0]=[7,8] print(list_) print(newlist) The newlist still display [[1, 2], [3, 4]]. But list_[0] is a list which is mutable.
– Alston
Nov 12 '16...
Rails: around_* callbacks
...classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
...
How to limit the maximum value of a numeric field in a Django model?
...go.db import models
class IntegerRangeField(models.IntegerField):
def __init__(self, verbose_name=None, name=None, min_value=None, max_value=None, **kwargs):
self.min_value, self.max_value = min_value, max_value
models.IntegerField.__init__(self, verbose_name, name, **kwargs)
...
Dynamically updating plot in matplotlib
...t matplotlib.pyplot as plt
import numpy
hl, = plt.plot([], [])
def update_line(hl, new_data):
hl.set_xdata(numpy.append(hl.get_xdata(), new_data))
hl.set_ydata(numpy.append(hl.get_ydata(), new_data))
plt.draw()
Then when you receive data from the serial port just call update_line.
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Determine if 2 lists have the same elements, regardless of order? [duplicate]
...side of the esoteric case of unhashable and unsortable elements.
def equal_ignore_order(a, b):
""" Use only when elements are neither hashable nor sortable! """
unmatched = list(b)
for element in a:
try:
unmatched.remove(element)
except ValueError:
...
Slow Requests on Local Flask Server
...sk run --with-threads which solved my problem.
– arno_v
Apr 13 '18 at 11:33
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show 1 more comment
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Why does Go have a “goto” statement
... x = x + 1
}
if x == 2 {
return z
}
x = x - 2
p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
return z * p / q
small:
if x == 0 ...
Is there a way to crack the password on an Excel VBA Project?
...m (nick name), a Vietnamese developer
Option Explicit
Private Const PAGE_EXECUTE_READWRITE = &H40
Private Declare Sub MoveMemory Lib "kernel32" Alias "RtlMoveMemory" _
(Destination As Long, Source As Long, ByVal Length As Long)
Private Declare Function VirtualProtect Lib "kernel32" ...
Any way to properly pretty-print ordered dictionaries?
...well if you don't care about the order of the keys. Personally, I wish the __repr__ for OrderedDict would produce output like this but preserve the order of the keys.
– ws_e_c421
Sep 24 '15 at 15:54
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