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What's the difference between ConcurrentHashMap and Collections.synchronizedMap(Map)?
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Please also note that the ConcurrentHashMap does not allow null keys or values. So they are NOT equal alternatives of a synchronized map.
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Is it ok to use dashes in Python files when trying to import them?
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One other thing to note in your code is that import is not a function. So import(python-code)...
Xcode 6 - How to pick signing certificate/provisioning profile for Ad-Hoc distribution?
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AlexHsiehAlexHsieh
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Importing modules from parent folder
...eraldo Good questions. PYTHONPATH env var is untouched. This installs into site-packages, which is already on sys.path and where the code would typically be installed by end users. That's better than sys.path hacks (and you can include using PYTHONPATH in that category of path hacks) because it mean...
Remove rows with all or some NAs (missing values) in data.frame
...mptions --------------------
fakeData <- function(m, n, p){
set.seed(123)
m <- matrix(runif(m*n), nrow=m, ncol=n)
m[m<p] <- NA
return(m)
}
df <- cbind( data.frame(id = paste0('ID',seq(row_size)),
stringsAsFactors = FALSE),
data.frame(fak...
Import / Export database with SQL Server Server Management Studio
...Microsoft SQL Server 2008 Management Studio Express from the Microsoft web site: http://www.microsoft.com/en-us/download/details.aspx?id=7593
After Microsoft SQL Server Management Studio Express has been installed, launch the application to connect to the system database. The "Connect to Server" dia...
Input placeholders for Internet Explorer
...uires jQuery) and takes just a couple minutes to implement for your entire site. It offers grey text at first, light grey when in focus, and black when typing. It also offers the placeholder text whenever the input field is empty.
First set up your form and include your placeholder attributes on t...
How to hide output of subprocess in Python 2.7
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Here's a more portable version (just for fun, it is not necessary in your case):
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from subprocess import Popen, PIPE, STDOUT
try:
from subprocess import DEVNULL # py3k
except ImportError:
import os
DEVNULL =...
HTTP status code for update and delete?
...atus code is the request sent by the client is valid (DELETE mySite/entity/123) and the entity to delete does not exist.
– Martin
Dec 30 '11 at 21:27
69
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How do I print a double value without scientific notation using Java?
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123
You could use printf() with %f:
double dexp = 12345678;
System.out.printf("dexp: %f\n", dexp)...