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Preferred method to store PHP arrays (json_encode vs serialize)
...2.180496931076 seconds
JSON decoded in 9.8368630409241 seconds
serialized "String" size : 13993
Native PHP :
PHP serialized in 2.9125759601593 seconds
PHP unserialized in 6.4348418712616 seconds
serialized "String" size : 20769
Igbinary :
WIN igbinary serialized in 1.6099879741669 secon...
Subset of rows containing NA (missing) values in a chosen column of a data frame
...olumn (in the example it would be column Var2) has there an 'NA' character string (I will replace it with your second statement), then I would like to choose the entire row to be part of the new data frame.
– John
Nov 2 '11 at 14:29
...
Which @NotNull Java annotation should I use?
...get({FIELD, METHOD, PARAMETER, LOCAL_VARIABLE})
public @interface NotNull {String value() default "";}
package javax.annotation;
@TypeQualifier
@Retention(RUNTIME)
public @interface Nonnull {
When when() default When.ALWAYS;
static class Checker implements TypeQualifierValidator<Nonnu...
How can I check if an ip is in a network in Python?
...lt;<n-1) - 1
def dottedQuadToNum(ip):
"convert decimal dotted quad string to long integer"
return struct.unpack('L',socket.inet_aton(ip))[0]
def networkMask(ip,bits):
"Convert a network address to a long integer"
return dottedQuadToNum(ip) & makeMask(bits)
def addressInNet...
How do you run a SQL Server query from PowerShell?
...here is the function that I use:
function Invoke-SQL {
param(
[string] $dataSource = ".\SQLEXPRESS",
[string] $database = "MasterData",
[string] $sqlCommand = $(throw "Please specify a query.")
)
$connectionString = "Data Source=$dataSource; " +
"In...
Haskell Type vs Data Constructor
...e to you.
Intermission
If you'd want to construct a binary tree to store Strings, you could imagine doing something like
data SBTree = Leaf String
| Branch String SBTree SBTree
What we see here is a type SBTree that contains two data constructors. In other words, there are two funct...
“Items collection must be empty before using ItemsSource.”
...ou caught the error yet? -->
</ItemsControl>
The bug? The extra > after the initial opening <ItemsControl> tag! The < got applied to the built-in Items collection. When the DataContext was later set, instant crashola. So look out for more than just errors surround you...
How do I find the location of the executable in C? [duplicate]
...tModuleFileName. Instead, just #include <windows.h> and use the path string provided automatically by Windows in _pgmptr. It's easier than using the GetModuleFileName function because that has the possibility of failing.
– rsethc
May 1 '13 at 1:43
...
How to loop through all enum values in C#? [duplicate]
...
static void Main(string[] args)
{
foreach (int value in Enum.GetValues(typeof(DaysOfWeek)))
{
Console.WriteLine(((DaysOfWeek)value).ToString());
}
foreach (string value in Enum.GetNames(typeof(DaysOfWeek)))
{
...
MySQL Error 1215: Cannot add foreign key constraint
... @www.jensolsson.se You are correct, if the PK includes one or more string columns then they must use the same character set and collation. In this specific case the PK was an INT so the character set of the table and/or columns was not relevant.
– Ike Walker
...