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How to do a join in linq to sql with method syntax?
...eOtherClass
on sc.Property1 equals soc.Property2
select new { SomeClass = sc, SomeOtherClass = soc };
Would be equivalent to:
var result = enumerableOfSomeClass
.Join(enumerableOfSomeOtherClass,
sc => sc.Property1,
soc => soc.Property2,
...
live output from subprocess command
...ptimization: If we are only using one pipe, or no pipe at
# all, using select() or threads is unnecessary.
if [self.stdin, self.stdout, self.stderr].count(None) >= 2:
But, alas, here we've made at least two, and maybe three, different pipes, so the count(None) returns either 1 or 0. We...
How do I create test and train samples from one dataframe with pandas?
...
scikit learn's train_test_split is a good one.
from sklearn.model_selection import train_test_split
train, test = train_test_split(df, test_size=0.2)
share
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improve this answer
...
Array or List in Java. Which is faster?
...;std::string>, although copying by value without a pointer as such, the character arrays will form an object for string (and these will not usually be shared).
If this particular code is really performance-sensitive, you could create a single char[] array (or even byte[]) for all the characters ...
What is the advantage of using heredoc in PHP? [closed]
...e day I used to use them to construct SQL queries:
$sql = <<<SQL
select *
from $tablename
where id in [$order_ids_list]
and product_name = "widgets"
SQL;
To me this has a lower probability of introducing a syntax error than using quotes:
$sql = "
select *
from $tablename
where ...
MongoDB SELECT COUNT GROUP BY
I am playing around with MongoDB trying to figure out how to do a simple
7 Answers
7
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Error “The connection to adb is down, and a severe error has occurred.”
... I solved my issue. I go to Task Manager in windows7 -> processes -> selected the adb.exe -> End Process. After that I go to cmd prompt and type adb start-server. This time adb statred succefully. I run eclipe and it was showing no error.
– Nishant
Apr...
Reading/writing an INI file
...bly.GetExecutingAssembly().GetName().Name;
[DllImport("kernel32", CharSet = CharSet.Unicode)]
static extern long WritePrivateProfileString(string Section, string Key, string Value, string FilePath);
[DllImport("kernel32", CharSet = CharSet.Unicode)]
static extern in...
Similar to jQuery .closest() but traversing descendants?
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These examples all select depth-first descendants, not breadth-first, so these can't be used to solve the original question. In my testing they all returned the first span, not the second.
– JrBaconCheez
M...
querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
I would like to know what exactly is the difference between querySelector and querySelectorAll against getElementsByClassName and getElementById ?
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