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Mapping over values in a python dictionary
...t 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 no such method on lists...
Getting the first character of a string with $str[0]
...string : Note: Strings may also be accessed using braces, as in $str{42}, for the same purpose. However, this syntax is deprecated as of PHP 5.3.0. Use square brackets instead, such as $str[42].
– VolkerK
Dec 29 '09 at 0:24
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Matplotlib (pyplot) savefig outputs blank image
...o deal with this, you can
Call plt.savefig('tessstttyyy.png', dpi=100) before you call plt.show()
Save the figure before you show() by calling plt.gcf() for "get current figure", then you can call savefig() on this Figure object at any time.
For example:
fig1 = plt.gcf()
plt.show()
plt.draw()
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How to list the contents of a package using YUM?
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To search faster for installed packages, include --installed option. eg $ repoquery -lq --installed time.
– Mohsenme
Mar 5 '14 at 8:06
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Bash Templating: How to build configuration files from templates with Bash?
I'm writing a script to automate creating configuration files for Apache and PHP for my own webserver. I don't want to use any GUIs like CPanel or ISPConfig.
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Better way to check variable for null or empty string?
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// Function for basic field validation (present and neither empty nor only white space
function IsNullOrEmptyString($str){
return (!isset($str) || trim($str) === '');
}
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Remove duplicates from an array of objects in JavaScript
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A primitive method would be:
var obj = {};
for ( var i=0, len=things.thing.length; i < len; i++ )
obj[things.thing[i]['place']] = things.thing[i];
things.thing = new Array();
for ( var key in obj )
things.thing.push(obj[key]);
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How to convert ActiveRecord results into an array of hashes
...ash and you can convert any ActiveRecord results to an Array with to_a, so for your example :
tasks_records = TaskStoreStatus.all
tasks_records.to_a.map(&:serializable_hash)
And if you want an ugly solution for Rails prior to v2.3
JSON.parse(tasks_records.to_json) # please don't do it
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Weak and strong property setter attributes in Objective-C
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You either have ARC on or off for a particular file. If its on you cannot use retain release autorelease etc... Instead you use strong weak for properties or __strong
__weak
for variables (defaults to __strong). Strong is the equivalent to retain, how...
Omitting all xsi and xsd namespaces when serializing an object in .NET?
...add that removing the default namespace can have unintended consequences : for instance, if you use the XmlInclude attribute to serialize derived types, the namespaces will be added to each of these elements, whether you want it or not, because they're necessary for deserialization
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