大约有 13,922 项符合查询结果（耗时：0.0239秒） [XML]
How to prove that a problem is NP complete?
...te a polynomial time algorithm V that will verify for every possible input X whether X is in your domain or not.
Example
Prove that the problem of vertex covers (that is, for some graph G, does it have a vertex cover set of size k such that every edge in G has at least one vertex in the cover set?) ...
LINQ where vs takewhile
..., 5, -1, -2 };
Console.WriteLine("Where");
foreach (var i in intList.Where(x => x <= 3))
Console.WriteLine(i);
Console.WriteLine("TakeWhile");
foreach (var i in intList.TakeWhile(x => x <= 3))
Console.WriteLine(i);
Gives
Where
1
2
3
-1
-2
TakeWhile
1
2
3
...
How to install python modules without root access?
...ution works for you.
With easy_install you can do:
easy_install --prefix=$HOME/local package_name
which will install into
$HOME/local/lib/pythonX.Y/site-packages
(the 'local' folder is a typical name many people use, but of course you may specify any folder you have permissions to write in...
Zoom in on a point (using scale and translate)
...e viewport position accordingly:
scalechange = newscale - oldscale;
offsetX = -(zoomPointX * scalechange);
offsetY = -(zoomPointY * scalechange);
So really you can just pan over down and to the right when you zoom in, by a factor of how much you zoomed in, relative to the point you zoomed at.
...
How to set a default value with Html.TextBoxFor?
...lper from ASP.NET MVC Framework 1 it is easy to set a default value on a textbox because there is an overload Html.TextBox(string name, object value) . When I tried using the Html.TextBoxFor method, my first guess was to try the following which did not work:
...
How do getters and setters work?
I'm from the php world. Could you explain what getters and setters are and could give you some examples?
6 Answers
...
What is “entropy and information gain”?
...
I assume entropy was mentioned in the context of building decision trees.
To illustrate, imagine the task of learning to classify first-names into male/female groups. That is given a list of names each labeled with either m or f, we want to learn a model that fits th...
What to put in a python module docstring? [closed]
...t a minimum, it should document the functions and classes that the module exports, but I've also seen a few modules that list author names, copyright information, etc. Does anyone have an example of how a good python docstring should be structured?
...
How do I create a variable number of variables?
...h this. Dictionaries are stores of keys and values.
>>> dct = {'x': 1, 'y': 2, 'z': 3}
>>> dct
{'y': 2, 'x': 1, 'z': 3}
>>> dct["y"]
2
You can use variable key names to achieve the effect of variable variables without the security risk.
>>> x = "spam"
>>...
Function to calculate distance between two coordinates
...istance).
alert(calcCrow(59.3293371,13.4877472,59.3225525,13.4619422).toFixed(1));
//This function takes in latitude and longitude of two location and returns the distance between them as the crow flies (in km)
function calcCrow(lat1, lon1, lat2, lon2)
{
var R = 6371; // km
...