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How does delete[] know it's an array?
...eed the delete[] syntax at all? Why can't a single delete form be used to handle all deletes?
The answer to this goes back to C++'s roots as a C-compatible language (which it no longer really strives to be.) Stroustrup's philosophy was that the programmer should not have to pay for any features tha...
Create new user in MySQL and give it full access to one database
I want to create a new user in MySQL and give it full access only to one database, say dbTest , that I create with a command like create database dbTest; . What would be the MySQL commands to do that?
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How do I use itertools.groupby()?
I haven't been able to find an understandable explanation of how to actually use Python's itertools.groupby() function. What I'm trying to do is this:
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Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
Is there any difference between :key => "value" (hashrocket) and key: "value" (Ruby 1.9) notations?
5 Answers
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src/lxml/etree_defs.h:9:31: fatal error: libxml/xmlversion.h: No such file or directory
... Notice for Ubuntu 13.04 users: if you have libxml2 already installed and upgraded to version 2.9.0+dfsg1-4ubuntu4.3 you need to downgrade it to 2.9.0+dfsg1-4ubuntu4.1 by typing the command sudo apt-get install libxml2=2.9.0+dfsg1-4ubuntu4.1 otherwise the libxml2-dev wont be installed due versi...
Function return value in PowerShell
...ere are two main ideas to wrap your head around:
All output is captured, and returned
The return keyword really just indicates a logical exit point
Thus, the following two script blocks will do effectively the exact same thing:
$a = "Hello, World"
return $a
$a = "Hello, World"
$a
return
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Detect & Record Audio in Python
...ssing. The problem is that I need to determine when there is audio present and then record it, stop when it goes silent and then pass that file to the processing module.
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How can I find non-ASCII characters in MySQL?
...haracter class in the regular expression. For example, if periods, commas, and hyphens are OK, change the query to:
SELECT * FROM tableName WHERE columnToCheck NOT REGEXP '[A-Za-z0-9.,-]';
The most relevant page of the MySQL documentation is probably 12.5.2 Regular Expressions.
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How to exit a function in bash
...pecified by N. If N is omitted, the return status is that of the
last command executed within the function or script.
Exit Status:
Returns N, or failure if the shell is not executing a function or script.
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Getting vertical gridlines to appear in line plot in matplotlib
I want to get both horizontal and vertical grid lines on my plot but only the horizontal grid lines are appearing by default. I am using a pandas.DataFrame from an sql query in python to generate a line plot with dates on the x-axis. I'm not sure why they do not appear on the dates and I have trie...