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MySQL vs MongoDB 1000 reads
I have been very excited about MongoDb and have been testing it lately. I had a table called posts in MySQL with about 20 million records indexed only on a field called 'id'.
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What is memoization and how can I use it in Python?
I just started Python and I've got no idea what memoization is and how to use it. Also, may I have a simplified example?
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Python argparse mutual exclusive group
...ns within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
prog
command 1
-a: ...
command 2
-b: ...
-c: ...
To invoke with the first set of arguments:
prog command_1 -a xxxx
To invoke with the sec...
How to count certain elements in array?
... to use the right tool for the job" -requests never made much sense to me. And we can argue what is most elegant. E.g. for me, making a function call per element to just to compare it to a value is not elegant.
– Felix Kling
May 25 '11 at 8:33
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How to generate a random number between a and b in Ruby?
To generate a random number between 3 and 10, for example, I use: rand(8) + 3
8 Answers
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Could not load file or assembly or one of its dependencies
...ce the ServiceLocator you should provide it with the old version of Unity, and that makes the problem.
May be the output folder where all projects build their assemblies, has an old version of unity.
You can use FusLogVw to find out who is loading the old assemblies, just define a path for the log...
Can I store the .git folder outside the files I want tracked?
...e git as a backup system. So let's say I have a directory ./backup/myfiles and I want to back that up using git. To keep things clean I don't want to have a .git directory in the myfiles folder, so I thought I could create ./backup/git_repos/myfiles. From looking at the git docs, I've tried doing th...
How to calculate an angle from three points? [closed]
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Only a handful of languages use a caret for 'power of', so if you don't want to call it arcos, please just type cos⁻¹. (If you're using a commercial operating system that makes it difficult to type exponents, I expect there would ...
Merge 2 arrays of objects
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This is so far the simplest use and works just fine. Thanks for sharing it.
– Leo Caseiro
Jun 22 '16 at 7:51
18
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&& (AND) and || (OR) in IF statements
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No, it will not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write:
if (str != null && !str.isEmpty()) {
doSomethingWith(str.charAt(0));
}
or, the other way around
if ...