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How is “int* ptr = int()” value initialization not illegal?
...fined "integer constant expression with the value 0, or such an expression cast to type void *".
– Jerry Coffin
Nov 9 '11 at 16:52
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The performance impact of using instanceof in Java
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If "object" is an instance of ObjT, casting it is a little faster than doing an instanceof, but the difference my quick test found was 10-20ms over 10,000,000 iterations. If "object" isn't an ObjT, though, catching the exception was over 3000x slower - over 31,...
How can I obtain the element-wise logical NOT of a pandas Series?
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NumPy is slower because it casts the input to boolean values (so None and 0 becomes False and everything else becomes True).
import pandas as pd
import numpy as np
s = pd.Series([True, None, False, True])
np.logical_not(s)
gives you
0 False
1 ...
How can I get the SQL of a PreparedStatement?
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It doesn't work and throws ClassCastException: java.lang.ClassCastException: oracle.jdbc.driver.T4CPreparedStatement cannot be cast to com.mysql.jdbc.JDBC4PreparedStatement
– Ercan
Apr 4 '19 at 13:15
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How do you select a particular option in a SELECT element in jQuery?
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A selector to get the middle option-element by value is
$('.selDiv option[value="SEL1"]')
For an index:
$('.selDiv option:eq(1)')
For a known text:
$('.selDiv option:contains("Selection 1")')
EDIT: As commented above t...
jQuery If DIV Doesn't Have Class “x”
...y I need to do an if statement to see if $this doesn't contain the class '.selected'.
7 Answers
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SQL Server SELECT into existing table
I am trying to select some fields from one table and insert them into an existing table from a stored procedure. Here is what I am trying:
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Nullable vs. int? - Is there any difference?
...tions is clearly named logical. Remember, in C# there are no conversions ("casts") between bool and numeric types!
– Jeppe Stig Nielsen
Aug 14 '15 at 10:41
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Can an Option in a Select tag carry multiple values?
I got a select tag with some options in a HTML form:
(the data will be collected and processed using PHP)
15 Answers
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Ruby on Rails form_for select field with class
I am beating my head against the wall on this one. I want to make a simple select tag using the f.select tag but nothing I do works. I put an example below:
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