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Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
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How to deal with SettingWithCopyWarning in Pandas?
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The SettingWithCopyWarning was created to flag potentially confusing "chained" assignments, such as the following, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2...
Entity Framework DateTime and UTC
...y Framework (I am using the Code First Approach with CTP5 currently) store all DateTime values as UTC in the database?
13 A...
powershell 2.0 try catch how to access the exception
...tch [Net.WebException] {
$_ | fl * -Force
}
I think it will give you all the info you need.
My rule: if there is some data that is not displayed, try to use -force.
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What is the most efficient way to loop through dataframes with pandas? [duplicate]
...Note that iterrows is very slow (it converts every row to a series, potentially messing with your data types). When you need an iterator, better to use itertuples
– joris
Jul 29 '15 at 15:46
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What is the difference between typeof and instanceof and when should one be used vs. the other?
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@Luke generally a bad idea to use "new String" like this. that creates a "string object" rather than a string primitive. see section here developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…
– Colin D
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glob exclude pattern
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Really interesting solution! But my case is going to be extremely slow to make a read twice. Also if the content of a folder is big on an network directory, is going to be slow again. But in any case, really handy.
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SQLite - UPSERT *not* INSERT or REPLACE
...e columns in the table: ID, NAME, ROLE
BAD: This will insert or replace all columns with new values for ID=1:
INSERT OR REPLACE INTO Employee (id, name, role)
VALUES (1, 'John Foo', 'CEO');
BAD: This will insert or replace 2 of the columns... the NAME column will be set to NULL or the def...
How can I get nth element from a list?
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Personally I can't comprehend how an at-index accessor that doesn't return a Maybe type is acceptable as idiomatic Haskell. [1,2,3]!!6 will give you a runtime error. It could very easily be avoided if !! had the type [a] -> Int ...
Copy folder recursively, excluding some folders
...kHuginnsson - What systems are you using? Rsync is included by default in all mainstream Linux distros I know of, including RHEL, CentOS, Debian, and Ubuntu, and I believe it's in FreeBSD as well.
– siliconrockstar
Jan 30 '15 at 19:50
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