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PHP regular expressions: No ending delimiter '^' found in
...
PHP regex strings need delimiters. Try:
$numpattern="/^([0-9]+)$/";
Also, note that you have a lower case o, not a zero. In addition, if you're just validating, you don't need the capturing group, and can simplify the regex to /^\d+$/.
Example: http://ideone.com/Ec3zh
See also:...
How to count items in a Go map?
...ed from the now-retired SO documentation:
m := map[string]int{}
len(m) // 0
m["foo"] = 1
len(m) // 1
If a variable points to a nil map, then len returns 0.
var m map[string]int
len(m) // 0
Excerpted from Maps - Counting map elements. The original author was Simone Carletti. Attribution det...
Swift equivalent for MIN and MAX macros
... JackJack
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2
...
Which, if any, C++ compilers do tail-recursion optimization?
...s such as:
int bar(int, int);
int foo(int n, int acc) {
return (n == 0) ? acc : bar(n - 1, acc + 2);
}
int bar(int n, int acc) {
return (n == 0) ? acc : foo(n - 1, acc + 1);
}
Letting the compiler do the optimisation is straightforward: Just switch on optimisation for speed:
For MSVC,...
Matplotlib plots: removing axis, legends and white spaces
...
406
I think that the command axis('off') takes care of one of the problems more succinctly than cha...
is node.js' console.log asynchronous?
...
102
Update: Starting with Node 0.6 this post is obsolete, since stdout is synchronous now.
Well le...
Why use softmax as opposed to standard normalization?
...
170
There is one nice attribute of Softmax as compared with standard normalisation.
It react to lo...
How to find out element position in slice?
...
70
Sorry, there's no generic library function to do this. Go doesn't have a straight forward way of...
Is it possible to figure out the parameter type and return type of a lambda?
..._traits implementation based on Specializing a template on a lambda in C++0x which can give the parameter types. The trick, as described in the answer in that question, is to use the decltype of the lambda's operator().
template <typename T>
struct function_traits
: public function_trai...
How do I space out the child elements of a StackPanel?
...ype="{x:Type TextBox}">
<Setter Property="Margin" Value="0,10,0,0"/>
</Style>
</StackPanel.Resources>
<TextBox Text="Apple"/>
<TextBox Text="Banana"/>
<TextBox Text="Cherry"/>
</StackPanel>
EDIT: In case you would wa...
