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Can't find the 'libpq-fe.h header when trying to install pg gem
...on Rails 3.1 pre version. I like to use PostgreSQL, but the problem is installing the pg gem. It gives me the following error:
...
How to call a Parent Class's method from Child Class in Python?
...P was asking how to do it without explicitly naming the superclass at the call site (Bar, in this case).
– Adam Rosenfield
Apr 30 '09 at 2:13
8
...
What is “assert” in JavaScript?
...on is false; this is part of the general concept of assertion checking. Usually assertions (as they're called) are used only in "testing" or "debug" builds and stripped out of production code.
Suppose you had a function that was supposed to always accept a string. You'd want to know if someone call...
Python unit test with base and sub class
...test
class CommonTests(object):
def testCommon(self):
print 'Calling BaseTest:testCommon'
value = 5
self.assertEquals(value, 5)
class SubTest1(unittest.TestCase, CommonTests):
def testSub1(self):
print 'Calling SubTest1:testSub1'
sub = 3
sel...
How to normalize a NumPy array to within a certain range?
...p.max(np.abs(audio),axis=0)
image *= (255.0/image.max())
Using /= and *= allows you to eliminate an intermediate temporary array, thus saving some memory. Multiplication is less expensive than division, so
image *= 255.0/image.max() # Uses 1 division and image.size multiplications
is margi...
WPF Auto height in code
...
Perhaps this link will help you.
At times, you may want to
programmatically set the Height or
Width of a WPF element to Auto in
code. To do this, just use the
Double.NaN (Not a Number) value.
For example, in C#:
this.txtName.Width = Double.NaN;
...
Margin-Top push outer div down
... this is an old issue, I've come across it many times. The problem is that all of the fixes here are hacks that would potentially have unintended consequences.
First off, there's an easy explanation for the root problem. Due to the way that margin collapsing works, if the first element inside a co...
Difference between the 'controller', 'link' and 'compile' functions when defining a directive
...ulation of tElement = template element), hence manipulations that apply to all DOM clones of the template associated with the directive. (If you also need a link function (or pre and post link functions), and you defined a compile function, the compile function must return the link function(s) beca...
How to cache data in a MVC application
...
I agree with Oli.. getting the results from the actual call to the DB is better than getting them from the cache
– CodeClimber
Jul 8 '09 at 21:48
1
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How to check if activity is in foreground or in visible background?
...cation panel, then neither the onPause, onStop, nor the onResume event is called. So what do you do then if none of these events are fired?!
– user4750643
Jul 9 '15 at 15:56
1
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