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Can't find the PostgreSQL client library (libpq)
I'm trying to install PostgreSQL for Rails on Mac OS X 10.6. First I tried the MacPorts install but that didn't go well so I did the one-click DMG install. That seemed to work.
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python: how to identify if a variable is an array or a scalar
...ad of list.
note: isinstance also supports a tuple of classes, check type(x) in (..., ...) should be avoided and is unnecessary.
You may also wanna check not isinstance(x, (str, unicode))
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What are free monads?
... some time, but everyone just seems to use/discuss them without giving an explanation of what they are. So: what are free monads? (I'd say I'm familiar with monads and the Haskell basics, but have only a very rough knowledge of category theory.)
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Relative frequencies / proportions with dplyr
...nt to calculate the proportion of different values within each group. For example, using the mtcars data, how do I calculate the relative frequency of number of gears by am (automatic/manual) in one go with dplyr ?
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How do you make an array of structs in C?
...nt month;
int year;
}STUDENT;
int numStudents=3;
int x;
STUDENT* students = malloc(numStudents * sizeof *students);
for (x = 0; x < numStudents; x++){
students[x].firstName=(char*)malloc(sizeof(char*));
scanf("%s",students[x].firstName);
stude...
How to create “No Activate” form in Firemonkey
In XCode by adding these methods to your NSView subclass can prevent the window from becoming active when clicking on it:
2...
Are +0 and -0 the same?
... +0 = 0. However, in computing, some number representations allow for the existence of two zeros, often denoted by −0 (negative zero) and +0 (positive zero). This occurs in some signed number representations for integers, and in most floating point number representations. The number 0 is usually e...
How can I set the color of a selected row in DataGrid
...such as linear gradient.
<DataGrid.Resources>
<SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}"
Color="#FF0000"/>
</DataGrid.Resources>
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Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
...t, 32-bit machine)(from here):
unsigned int
reverse(register unsigned int x)
{
x = (((x & 0xaaaaaaaa) >> 1) | ((x & 0x55555555) << 1));
x = (((x & 0xcccccccc) >> 2) | ((x & 0x33333333) << 2));
x = (((x & 0xf0f0f0f0) >> 4) | ((x & 0x0...
Histogram Matplotlib
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import matplotlib.pyplot as plt
import numpy as np
mu, sigma = 100, 15
x = mu + sigma * np.random.randn(10000)
hist, bins = np.histogram(x, bins=50)
width = 0.7 * (bins[1] - bins[0])
center = (bins[:-1] + bins[1:]) / 2
plt.bar(center, hist, align='center', width=width)
plt.show()
The object-...