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How to split a string in Java
... *, the plus sign +, the opening parenthesis (, the closing parenthesis ), and the opening square bracket [, the opening curly brace {, These special characters are often called "metacharacters".
So, if you want to split on e.g. period/dot . which means "any character" in regex, use either backsla...
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...ch was causing all sorts of problems. I was inadvertently doing a bitwise AND instead of a logical AND .
6 Answers
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Can't compare naive and aware datetime.now()
I am trying to compare the current date and time with dates and times specified in models using comparison operators:
7 Ans...
Get difference between two lists
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@Drewdin: Lists do not support the "-" operand. Sets, however, do, and that what is demonstrated above if you look closely.
– Godsmith
Oct 14 '14 at 21:21
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Why is Dictionary preferred over Hashtable in C#?
... safety with Dictionary<TKey, TValue>, because you can't insert any random object into it, and you don't have to cast the values you take out.
Interestingly, the Dictionary<TKey, TValue> implementation in the .NET Framework is based on the Hashtable, as you can tell from this comment in...
User recognition without cookies or local storage
...--+-----+-----+-----+-----+-----------+
x1 to x20 represent the features converted by the code.
// Get RNA Labels
$labels = array();
$n = 1;
foreach ( $features as $k => $v ) {
$labels[$k] = "x" . $n;
$n ++;
}
Here is an online demo
Class Used:
class Profile {
public $name, $da...
Way to read first few lines for pandas dataframe
...e lines ahead of time? I have a large file that takes a long time to read, and occasionally only want to use the first, say, 20 lines to get a sample of it (and prefer not to load the full thing and take the head of it).
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What is the difference between a stored procedure and a view?
...A view represents a virtual table. You can join multiple tables in a view and use the view to present the data as if the data were coming from a single table.
A stored procedure uses parameters to do a function... whether it is updating and inserting data, or returning single values or data sets.
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Python List vs. Array - when to use?
...y, you can implement it as a List, or else use the 'array' module in the standard library. I have always used Lists for 1d arrays.
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How to get multiple counts with one SQL query?
...a.distributor_id,
(SELECT COUNT(*) FROM myTable WHERE level='personal' and distributor_id = a.distributor_id) as PersonalCount,
(SELECT COUNT(*) FROM myTable WHERE level='exec' and distributor_id = a.distributor_id) as ExecCount,
(SELECT COUNT(*) FROM myTable WHERE distributor_id = a.dis...