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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.
...
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?
...
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 bind RadioButtons to an enum?
...
return Enum.Parse(targetType, parameterString);
}
#endregion
}
And in the XAML-Part you use:
<Grid>
<Grid.Resources>
<l:EnumBooleanConverter x:Key="enumBooleanConverter" />
</Grid.Resources>
<StackPanel >
<RadioButton IsChecked="{...
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...
Add IIS 7 AppPool Identities as SQL Server Logons
...actually, it will find it, but it will think its an actual system account, and it will try to treat it as such...which won't work, and will give you the error message about it not being found).
How I've gotten it to work is:
In SQL Server Management Studio, look for the Security folder (the secu...
How to determine if a number is a prime with regex?
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You said you understand this part, but just to emphasize, the String generated has a length equal to the number supplied. So the string has three characters if and only if n == 3.
.?
The first part of the regex says, "any character, zero or o...