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In vim, how do I go back to where I was before a search?
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You really should read :help jumplist it explains all of this very well.
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Why does Java's hashCode() in String use 31 as a multiplier?
... i == (i << 5) - i. Modern VMs do this sort of optimization automatically.
(from Chapter 3, Item 9: Always override hashcode when you override equals, page 48)
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HashMap get/put complexity
...ever it depends on the hash implementation. The default object hash is actually the internal address in the JVM heap. Are we sure it is good enough to claim that the get/put are O(1) ?
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Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
How to write LDAP query to test if user is member of a group?
...OU=yourOU,DC=yourcompany,DC=com))";
SearchResultCollection res = srch.FindAll();
if(res == null || res.Count <= 0) {
Console.WriteLine("This user is *NOT* member of that group");
} else {
Console.WriteLine("This user is INDEED a member of that group");
}
Word of caution: this will onl...
Singular or plural controller and helper names in Rails
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Using plural names for controllers is just a convention.
Plural names usually sound more natural (especially for controllers that are tied directly to a specific model: User -> Users, etc.), but you can use whatever you want.
As for helpers, all helpers are available for all controllers by def...
Elastic Search: how to see the indexed data
...lore your ElasticSearch cluster is to use elasticsearch-head.
You can install it by doing:
cd elasticsearch/
./bin/plugin -install mobz/elasticsearch-head
Then (assuming ElasticSearch is already running on your local machine), open a browser window to:
http://localhost:9200/_plugin/head/
Alte...
How can I get the length of text entered in a textbox using jQuery?
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Up Vote because you explained what it all does, not jsut provided the code.
– user83632
May 2 '09 at 16:53
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How to define a custom ORDER BY order in mySQL
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MySQL has a handy function called FIELD() which is excellent for tasks like this.
ORDER BY FIELD(Language,'ENU','JPN','DAN'), ID
Note however, that
It makes your SQL less portable, as other DBMSs might not have such function
When your list of langua...
C/C++ check if one bit is set in, i.e. int variable
... "have" to do it this way. But I usually write:
/* Return type (8/16/32/64 int size) is specified by argument size. */
template<class TYPE> inline TYPE BIT(const TYPE & x)
{ return TYPE(1) << x; }
template<class TYPE> inline bool IsBitSet(const TYPE & x, const TYPE &...