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How to save an image locally using Python whose URL address I already know?
...wered Nov 27 '11 at 15:01
Liquid_FireLiquid_Fire
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...
Unable to install Maven on Windows: “JAVA_HOME is set to an invalid directory”
...e-maven-2.2.0\bin" is on your command search path.
Make sure that the JAVA_HOME variable refers to the home directory for your Java installation. If you are executing Java from "E:\Sun\SDK\jdk\bin", then the JAVA_HOME variable needs to point to "E:\Sun\SDK\jdk".
NB: JAVA_HOME should NOT end with "...
Convert Python dictionary to JSON array
...
If you are fine with non-printable symbols in your json, then add ensure_ascii=False to dumps call.
>>> json.dumps(your_data, ensure_ascii=False)
If ensure_ascii is false, then the return value will be a
unicode instance subject to normal Python str to unicode
coercion rules in...
Memoization in Haskell?
...alling, for example: fix f 123 = 144
We could memoize this by defining:
f_list :: [Int]
f_list = map (f faster_f) [0..]
faster_f :: Int -> Int
faster_f n = f_list !! n
That performs passably well, and replaces what was going to take O(n^3) time with something that memoizes the intermediate r...
How to check a radio button with jQuery?
...
For versions of jQuery equal or above (>=) 1.6, use:
$("#radio_1").prop("checked", true);
For versions prior to (<) 1.6, use:
$("#radio_1").attr('checked', 'checked');
Tip: You may also want to call click() or change() on the radio button afterwards. See comments for more info.
...
Plot two histograms on single chart with matplotlib
...dom
import numpy
from matplotlib import pyplot
x = [random.gauss(3,1) for _ in range(400)]
y = [random.gauss(4,2) for _ in range(400)]
bins = numpy.linspace(-10, 10, 100)
pyplot.hist(x, bins, alpha=0.5, label='x')
pyplot.hist(y, bins, alpha=0.5, label='y')
pyplot.legend(loc='upper right')
pyplot....
sizeof single struct member in C
...ic way to do it, another would be to use a macro like this:
#define member_size(type, member) sizeof(((type *)0)->member)
and use it like this:
typedef struct
{
float calc;
char text[255];
int used;
} Parent;
typedef struct
{
char flag;
char text[member_size(Parent, text)...
How to detect if a function is called as constructor?
... // except in in EcmaScript 5 strict mode.
&& !this.__previouslyConstructedByX) {
isConstructor = true;
this.__previouslyConstructedByX = true;
}
alert(isConstructor);
}
Obviously this is not ideal, since you now have an extra useless property on ever...
What is the definition of “interface” in object oriented programming
...dom.randint(0,10)
# What you care about
class SecretGame(object):
def __init__(self, number_generator):
number = number_generator.generate()
print number
Here, none of the classes implement an interface. Python does not care about that, because the SecretGame class will just t...
How to get position of a certain element in strings vector, to use it as an index in ints vector?
...nting to the element, simply subtract v.begin() from the iterator:
ptrdiff_t pos = find(Names.begin(), Names.end(), old_name_) - Names.begin();
Now you need to check pos against Names.size() to see if it is out of bounds or not:
if(pos >= Names.size()) {
//old_name_ not found
}
vector i...