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How to “set a breakpoint in malloc_error_break to debug”
...int Navigator or ⌘8), clicking the plus button in the lower left corner, and selecting "Add Symbolic Breakpoint". In the popup that comes up, enter malloc_error_break in the Symbol field, then click Done.
EDIT: openfrog added a screenshot and indicated that he's already tried these steps without s...
How do I implement an Objective-C singleton that is compatible with ARC?
How do I convert (or create) a singleton class that compiles and behaves correctly when using automatic reference counting (ARC) in Xcode 4.2?
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Replace string within file contents
How can I open a file, Stud.txt, and then replace any occurences of "A" with "Orange"?
8 Answers
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Sort array of objects by string property value
...are function body: return a.value - b.value; (ASC)
– Andre Figueiredo
Jan 8 '14 at 12:06
23
@Cerb...
When to use a “has_many :through” relation in Rails?
I am trying to understand what has_many :through is and when to use it (and how). However, I am not getting it. I am reading Beginning Rails 3 and I tried Googling, but I am not able to understand.
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“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
...Connector/J, configure the MySQL server with character_set_server=utf8mb4, and leave characterEncoding out of the Connector/J connection string. Connector/J will then autodetect the UTF-8 setting.
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Order of member constructor and destructor calls
Oh C++ gurus, I seek thy wisdom. Speak standardese to me and tell my if C++ guarantees that the following program:
4 Answer...
How to add an extra column to a NumPy array
...
I think a more straightforward solution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstac...
How to write inline if statement for print?
...n Python 2.5)
expression_if_true if condition else expression_if_false
And note, that both print a and b = a are statements. Only the a part is an expression. So if you write
print a if b else 0
it means
print (a if b else 0)
and similarly when you write
x = a if b else 0
it means
x = ...
Pandas read_csv low_memory and dtype options
...emory warning is because guessing dtypes for each column is very memory demanding. Pandas tries to determine what dtype to set by analyzing the data in each column.
Dtype Guessing (very bad)
Pandas can only determine what dtype a column should have once the whole file is read. This means nothing can...