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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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How to download image using requests

...flate). You can force it to decompress for you anyway by setting the decode_content attribute to True (requests sets it to False to control decoding itself). You can then use shutil.copyfileobj() to have Python stream the data to a file object: import requests import shutil r = requests.get(settin...
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Add Foreign Key to existing table

... To add a foreign key (grade_id) to an existing table (users), follow the following steps: ALTER TABLE users ADD grade_id SMALLINT UNSIGNED NOT NULL DEFAULT 0; ALTER TABLE users ADD CONSTRAINT fk_grade_id FOREIGN KEY (grade_id) REFERENCES grades(id); ...
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Remove characters except digits from string using Python?

...ion of "everything but" a few characters: import string class Del: def __init__(self, keep=string.digits): self.comp = dict((ord(c),c) for c in keep) def __getitem__(self, k): return self.comp.get(k) DD = Del() x='aaa12333bb445bb54b5b52' x.translate(DD) also emits '1233344554552'. ...
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How can I get the current screen orientation?

... This only provides two values ORIENTATION_PORTRAIT and ORIENTATION_LANDSCAPE. Is there a way to get all the four values from ActivityInfo? (That is LANDSCAPE_REVERSE and PORTRAIT_REVERSE as well) – HRJ May 4 '11 at 9:56 ...
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Mapping over values in a python dictionary

...ch function; the easiest way to do this is to use a dict comprehension: my_dictionary = {k: f(v) for k, v in my_dictionary.items()} In python 2.7, use the .iteritems() method instead of .items() to save memory. The dict comprehension syntax wasn't introduced until python 2.7. Note that there is ...
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How to do what head, tail, more, less, sed do in Powershell? [closed]

...txt | more # or less if you have it installed gc log.txt | %{ $_ -replace '\d+', '($0)' } # sed This works well enough for small files, larger ones (more than a few MiB) are probably a bit slow. The PowerShell Community Extensions include some cmdlets for specialised file stuf...
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How to query SOLR for empty fields?

...ou need to change QueryParameter.cs (Create a new parameter) private bool _negativeQuery = false; public QueryParameter(string field, string value, ParameterJoin parameterJoin = ParameterJoin.AND, bool negativeQuery = false) { this._field = field; this._value = value.Trim(); this._para...
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Convert hyphens to camel case (camelCase)

...and have it included in your project. var str = 'my-hyphen-string'; str = _.camelCase(str); // results in 'myHyphenString' share | improve this answer | follow ...
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How to reverse a string in Go?

...ints. n := 0 rune := make([]rune, len(input)) for _, r := range input { rune[n] = r n++ } rune = rune[0:n] // Reverse for i := 0; i < n/2; i++ { rune[i], rune[n-1-i] = rune[n-1-i], rune[i]...