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PHP check whether property exists in object or class

... property_exists( mixed $class , string $property ) if (property_exists($ob, 'a')) isset( mixed $var [, mixed $... ] ) if (isset($ob->a)) isset() will return false if property is null Example 1: $ob->a = null var_du...
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Unique BooleanField value in Django?

...rn it off). class Character(models.Model): name = models.CharField(max_length=255) is_the_chosen_one = models.BooleanField() def save(self, *args, **kwargs): if self.is_the_chosen_one: try: temp = Character.objects.get(is_the_chosen_one=True) ...
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How can we match a^n b^n with Java regex?

... testAll($r, $tests) { foreach ($tests as $test) { $isMatch = preg_match($r, $test, $groups); $groupsJoined = join('|', $groups); print("$test $isMatch $groupsJoined\n"); } } $tests = array('aaa', 'aaab', 'aaaxb', 'xaaab', 'b', 'abbb'); $r1 = '/^a+(?=b+)/'; # └...
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Can I run multiple programs in a Docker container?

... you to sepcify behaviour for each process such as autorestart=true, stdout_logfile, stderr_logfile etc. Take a look at docs.docker.com/engine/admin/using_supervisord – Andreas Lundgren Aug 12 '16 at 7:39 ...
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How to inherit from a class in javascript?

...sole issue?) // In the Chrome console you should be able to drill down the __proto__ chain // You can also look down the proto chain with Object.getPrototypeOf // (Equivalent to tiger.__proto__) console.log( Object.getPrototypeOf(tiger) ); // Mammal console.log( Object.getPrototypeOf(Object.getPro...
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Entity Framework - Code First - Can't Store List

... List of entities? how will the mapping be saved? – A_Arnold Aug 6 '18 at 15:16 Depends - most likely to a separate ta...
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How to use single storyboard uiviewcontroller for multiple subclass

... The code of line we are looking for is: object_setClass(AnyObject!, AnyClass!) In Storyboard -> add UIViewController give it a ParentVC class name. class ParentVC: UIViewController { var type: Int? override func awakeFromNib() { if type = 0 { ...
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Convert Rows to columns using 'Pivot' in SQL Server

...) which allows doesn't require that you explicitly name the different "FOR ____ IN (...)" – The Red Pea Aug 13 '15 at 22:03 1 ...
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momentJS date string add 5 days

....4 - use .add(5, 'd') (or .add(5, 'days')) instead of .add('d', 5) var new_date = moment(startdate, "DD-MM-YYYY").add(5, 'days'); Thanks @Bala for the information. UPDATED: March 21, 2014 This is what you'd have to do to get that format. Here's an updated fiddle startdate = "20.03.2014"; var ...
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Converting strings to floats in a DataFrame

... NOTE: pd.convert_objects has now been deprecated. You should use pd.Series.astype(float) or pd.to_numeric as described in other answers. This is available in 0.11. Forces conversion (or set's to nan) This will work even when astype will ...