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The model used to open the store is incompatible with the one used to create the store
...el select your new version of data model for current data model
THAT'S NOT ALL ) You should perform so called "light migration".
Go to your AppDelegate and find where the persistentStoreCoordinator is being created
Find this line if (![_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteS...
ViewPager and fragments — what's the right way to store fragment's state?
...agment will be placed. FragmentPagerAdapter.getItem(int position) is only called when a fragment for that position does not exist. After rotating, Android will notice that it already created/saved a fragment for this particular position and so it simply tries to reconnect with it with FragmentManage...
What does the JSLint error 'body of a for in should be wrapped in an if statement' mean?
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First of all, never use a for in loop to enumerate over an array. Never. Use good old for(var i = 0; i<arr.length; i++).
The reason behind this is the following: each object in JavaScript has a special field called prototype. Ever...
Is inline assembly language slower than native C++ code?
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Yes, most times.
First of all you start from wrong assumption that a low-level language (assembly in this case) will always produce faster code than high-level language (C++ and C in this case). It's not true. Is C code always faster than Java code? N...
How can you determine a point is between two other points on a line segment?
Let's say you have a two dimensional plane with 2 points (called a and b) on it represented by an x integer and a y integer for each point.
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Iterating through a JSON object
..._raw= raw.readlines()
json_object = json.loads(json_raw[0])
you should really just do:
json_object = json.load(raw)
You shouldn't think of what you get as a "JSON object". What you have is a list. The list contains two dicts. The dicts contain various key/value pairs, all strings. When you do j...
How can I get the current screen orientation?
...lues ORIENTATION_PORTRAIT and ORIENTATION_LANDSCAPE. Is there a way to get all the four values from ActivityInfo? (That is LANDSCAPE_REVERSE and PORTRAIT_REVERSE as well)
– HRJ
May 4 '11 at 9:56
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How to plot two columns of a pandas data frame using points?
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You can specify the style of the plotted line when calling df.plot:
df.plot(x='col_name_1', y='col_name_2', style='o')
The style argument can also be a dict or list, e.g.:
import numpy as np
import pandas as pd
d = {'one' : np.random.rand(10),
'two' : np.random.rand(...
How to get current timestamp in milliseconds since 1970 just the way Java gets
...e UNIX epoch, but the spec only says it must be the system-wide real time wall clock. There is no requirement for the steady_clock to match reality, only that it only move forward.
– Oz.
Jul 27 '15 at 23:22
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Makefile, header dependencies
...vided by the gnu preprocessor are a bit confusing. However, the removal of all directories from the build target with -MM is documented and not a bug [gpp]:
By default CPP takes the name of the main input file, deletes any
directory components and any file suffix such as ‘.c’, and appends ...