大约有 40,000 项符合查询结果（耗时：0.0561秒） [XML]
How to use the PI constant in C++
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On some (especially older) platforms (see the comments below) you might need to
#define _USE_MATH_DEFINES
and then include the necessary header file:
#include <math.h>
and the value of pi can be accessed via:
M_PI
In my math....
How to exit from Python without traceback?
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If sys.exit() is called in "main program stuff", the code above throws away the value passed to sys.exit. Notice that sys.exit raises SystemExit and the variable "e" will contain the exit code.
– bstpierre
...
How do I create a self-signed certificate for code signing on Windows?
...User\My
2) set the password for it:
$CertPassword = ConvertTo-SecureString
-String "my_passowrd" -Force –AsPlainText
3) Export it:
Export-PfxCertificate -Cert "cert:\CurrentUser\My\$($cert.Thumbprint)"
-FilePath "d:\selfsigncert.pfx" -Password $CertPassword
Your certificate s...
A simple command line to download a remote maven2 artifact to the local repository?
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Extra helpful for showing how to get the dependency plugin itself installed.
– Sergio Acosta
Apr 18 '10 at 6:49
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Debugging in Clojure? [closed]
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There's also dotrace, which allows you to look at the inputs and outputs of selected functions.
(use 'clojure.contrib.trace)
(defn fib[n] (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
(dotrace [fib] (fib 3))
produces the output:
TRACE t4425: (f...
How to make an HTTP request + basic auth in Swift
...ike this in Swift 3:
let username = "user"
let password = "pass"
let loginString = String(format: "%@:%@", username, password)
let loginData = loginString.data(using: String.Encoding.utf8)!
let base64LoginString = loginData.base64EncodedString()
// create the request
let url = URL(string: "http://...
month name to month number and vice versa in python
...ore comprehensive method that can also accept full month names
def month_string_to_number(string):
m = {
'jan': 1,
'feb': 2,
'mar': 3,
'apr':4,
'may':5,
'jun':6,
'jul':7,
'aug':8,
'sep':9,
'oct':10,
...
What's the difference between and
...API that used Object.)
Source: http://download.oracle.com/javase/tutorial/extra/generics/convert.html; it explains why the JDK's java.util.Collections class has a method with this signature:
public static <T extends Object & Comparable<? super T>> T max(
Collection<? extends...
What is the command to list the available avdnames
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List all your emulators: emulator -list-avds Run one of the listed emulators: emulator @name-of-your-emulator where emulator is under: ${ANDROID_SDK}/tools/emulator
– Dhiraj Himani
Jun 16 ...
How to concatenate properties from multiple JavaScript objects
...n Javascript.
The Object.assign() method is used to copy the values of all enumerable own properties from one or more source objects to a target object. It will return the target object.
MDN documentation on Object.assign()
var o1 = { a: 1 };
var o2 = { b: 2 };
var o3 = { c: 3 };
var...