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Eclipse error: 'Failed to create the Java Virtual Machine'
...swered Sep 4 '11 at 22:52
Matt BallMatt Ball
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Why does changing the returned variable in a finally block not change the return value?
...atement executes is the value returned by the method. The fact that the finally clause later changes the value of s (after the return statement completes) does not (at that point) change the return value.
Note that the above deals with changes to the value of s itself in the finally block, not to th...
bpftrace教程【官方】 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
bpftrace教程【官方】bpftrace_tutorial该教程通过12个简单小节帮助你了解bpftrace的使用。每一小节都是一行的命令，你可以立马运行并看到运行效果。该教程系列用来介绍bpftrace的概念。关于bpftrace的完整参考，见bpftr 该教程通过12...
Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
...t;> A + B
Counter({'c': 7, 'b': 5, 'd': 5, 'a': 1})
Counters are basically a subclass of dict, so you can still do everything else with them you'd normally do with that type, such as iterate over their keys and values.
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How to add column if not exists on PostgreSQL?
...statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THEN RAISE NOTICE 'column <column_name> already exists in <table_name>.';
END;
END;
$$
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Reflection - get attribute name and value on property
I have a class, lets call it Book with a property called Name. With that property, I have an attribute associated with it.
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Detecting request type in PHP (GET, POST, PUT or DELETE)
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By using
$_SERVER['REQUEST_METHOD']
Example
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
// The request is using the POST method
}
For more details please see the documentation for the $_SERVER variable.
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Calculate distance between two points in google maps V3
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@EmanuelePaolini - Mathematically, atan2(sqrt(a),sqrt(1-a)) = asin(sqrt(a)) = acos(sqrt(1-a)), but the atan2 version remains numerically better conditioned for all values of a.
– ChrisV
Dec 19 '14 at 18:00
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Nested defaultdict of defaultdict
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For an arbitrary number of levels:
def rec_dd():
return defaultdict(rec_dd)
>>> x = rec_dd()
>>> x['a']['b']['c']['d']
defaultdict(<function rec_dd at 0x7f0dcef81500>, {})
>>> print json.dumps(x)
{"a": {"b": {"c": {"d": {}}}}}
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UILabel with text of two different colors
...ike this:
NSMutableAttributedString *text =
[[NSMutableAttributedString alloc]
initWithAttributedString: label.attributedText];
[text addAttribute:NSForegroundColorAttributeName
value:[UIColor redColor]
range:NSMakeRange(10, 1)];
[label setAttributedText: text];
...