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Find MongoDB records where array field is not empty
... To me that's the correct approach, since it makes sure the array exists and is not empty.
– LeandroCR
Mar 19 '15 at 14:34
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How many levels of pointers can we have?
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The C standard specifies the lower limit:
5.2.4.1 Translation limits
276 The implementation shall be able to translate and execute at least one program that contains at least one instance of every one of the following limits...
How to run a makefile in Windows?
I have some demos that I downloaded and they come with a Makefile.win and a Makefile.sgi. How can I run these in Windows to compile the demos?
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What is the difference between getFields and getDeclaredFields in Java reflection
I'm a little confused about the difference between the getFields method and the getDeclaredFields method when using Java reflection.
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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...
No EditorOptionDefinition Export Found Error
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After a reboot and some more research I found this post from a blog. The error described is not the same error I am seeing, however, it was close enough to warrant a try.
Follow the steps:
Close Visual Studio
Open the folder: %LocalAppDa...
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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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
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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 = ...