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Python Infinity - Any caveats?
So Python has positive and negative infinity:
5 Answers
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MySQL, better to insert NULL or empty string?
...a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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Why is NaN not equal to NaN? [duplicate]
The relevant IEEE standard defines a numeric constant NaN (not a number) and prescribes that NaN should compare as not equal to itself. Why is that?
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cscope or ctags why choose one over the other? [closed]
I primarily use vim / gvim as an editor and am looking at using a combination of lxr (the Linux Cross Reference) and either cscope or ctags for exploring the kernel source. However, I haven't ever used either cscope or ctags and would like to hear why one might choose one over the other t...
How is the AND/OR operator represented as in Regular Expressions?
...ou want to build a the regex dynamically to contain other words than part1 and part2, and that you want order not to matter. If so you can use something like this:
((^|, )(part1|part2|part3))+$
Positive matches:
part1
part2, part1
part1, part2, part3
Negative matches:
part1, //with ...
Reference - What does this error mean in PHP?
This is a number of answers about warnings, errors, and notices you might encounter while programming PHP and have no clue how to fix them. This is also a Community Wiki, so everyone is invited to participate adding to and maintaining this list.
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Convert datetime to Unix timestamp and convert it back in python
I have dt = datetime(2013,9,1,11) , and I would like to get a Unix timestamp of this datetime object.
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What is this operator in MySQL?
I'm working on code written by a previous developer and in a query it says,
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How to check if all list items have the same value and return it, or return an “otherValue” if they
..., otherwise I need to use an “otherValue”. I can’t think of a simple and clear way of doing this.
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How to create a self-signed certificate with OpenSSL
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You can do that in one command:
openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365
You can also add -nodes (short for no DES) if you don't want to protect your private key with a passphrase. Otherwise it will prompt you for "...