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How to keep index when using pandas merge
I would like to merge two DataFrames , and keep the index from the first frame as the index on the merged dataset. However, when I do the merge, the resulting DataFrame has integer index. How can I specify that I want to keep the index from the left data frame?
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How to generate a number of most distinctive colors in R?
I am plotting a categorical dataset and want to use distinctive colors to represent different categories. Given a number n , how can I get n number of MOST distinctive colors in R? Thanks.
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How can I handle the warning of file_get_contents() function in PHP?
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Step 1: check the return code: if($content === FALSE) { // handle error here... }
Step 2: suppress the warning by putting an error control operator (i.e. @) in front of the call to file_get_contents():
$content = @file_get_contents($site);
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Which version of Python do I have installed?
...script on a Windows server. How can I know which version of Python I have, and does it even really matter?
22 Answers
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PDO closing connection
...ber of other reasons. When connecting or running a query, catch any error, and if it is "MySQL has gone away", attempt to connect again or run the query a second time.
– Frank Forte
Dec 14 '17 at 20:50
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How do ports work with IPv6?
...t changed between the two versions is the addressing scheme, DHCP [DHCPv6] and ICMP [ICMPv6]. So basically, anything TCP/UDP related, including the port range (0-65535) remains unchanged.
Edit: Port 0 is a reserved port in TCP but it does exist. See RFC793
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How to generate all permutations of a list?
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Starting with Python 2.6 (and if you're on Python 3) you have a standard-library tool for this: itertools.permutations.
import itertools
list(itertools.permutations([1, 2, 3]))
If you're using an older Python (<2.6) for some reason or are just...
ERROR: Error 1005: Can't create table (errno: 121)
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I searched quickly for you, and it brought me here. I quote:
You will get this message if you're trying to add a constraint with a
name that's already used somewhere else
To check constraints use the following SQL query:
SELECT
constraint_n...
Django CharField vs TextField
What is the difference between CharField() and TextField() in Django? The documentation says that CharField() should be used for smaller strings and TextField() should be used for larger strings. Okay, but where is the line drawn between "small" and "large"? What's going on under the ho...
How do I center floated elements?
I'm implementing pagination, and it needs to be centered. The problem is that the links need to be displayed as block, so they need to be floated. But then, text-align: center; doesn't work on them. I could achieve it by giving the wrapper div padding of left, but every page will have a different ...