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Random row selection in Pandas dataframe
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df_0.7 is not a valid name. Moreover, I suggest replacing df_rest = df.loc[~df.index.isin(df_0_7.index)] with df_rest = df.loc[df.index.difference(df_0_7.index)].
– Pietro Battiston
May 1 '18 at 15:24
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python assert with and without parenthesis
...remove parentheses?) if you ran it through a full interpreter, not through IDLE. Because assert is a keyword and not a function, you are actually passing in a tuple as the first argument and leaving off the second argument.
Recall that non-empty tuples evaluate to True, and since the assertion mes...
setState vs replaceState in React.js
...e, it throws out the current state, and replaces it with only what you provide. Usually setState is used unless you really need to remove keys for some reason; but setting them to false/null is usually a more explicit tactic.
While it's possible it could change; replaceState currently uses the obj...
When do I need to use a semicolon vs a slash in Oracle SQL?
...one) tool to execute SQL scripts - and the "correctness" of a script is validated using that tool. Similar to having one compiler for your programming language or one specific version of your runtime environment (Java 7, .Net 4.0, PHP 5.x, ...)
– a_horse_with_no_name
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LaTeX Optional Arguments
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Example from the guide:
\newcommand{\example}[2][YYY]{Mandatory arg: #2;
Optional arg: #1.}
This defines \example to be a command with two arguments,
referred to as #1 and #2 in the {<definition>}--noth...
Erasing elements from a vector
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Use the remove/erase idiom:
std::vector<int>& vec = myNumbers; // use shorter name
vec.erase(std::remove(vec.begin(), vec.end(), number_in), vec.end());
What happens is that remove compacts the elements that differ from the value to ...
How to merge 2 JSON objects from 2 files using jq?
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"value4": 4
}
},
"status": 200
}
If you also want to get rid of the other keys (like your expected result), one way to do it is this:
jq -s '.[0] * .[1] | {value: .value}' file1 file2
Or the presumably somewhat more efficient (because it doesn't merge any other values):
jq -s '....
Enums and Constants. Which to use when?
.... There isn't a range of PI values, there is just PI.
Other points to consider are:
a: Constants don't necessarily indicate a relationship between the constants, whereas an enumeration indicates that something can be one of the set defined by the enum.
b: A defined enumeration can help you with t...
Why does this code segfault on 64-bit architecture but work fine on 32-bit?
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@vlad - the better idea is to always declare functions rather than rely upon implicit declarations for exactly this reason. (And not cast the return from malloc)
– Flexo♦
Sep 25 '11 at 12:19
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Pelican 3.3 pelican-quickstart error “ValueError: unknown locale: UTF-8”
...me assumptions about the format of locale names that aren't universally valid. Explicitly setting these environment vars is basically just a workaround for that bug.
[Edit:] As @asmeurer correctly points out, the above fix assumes English and the U.S. You should really pick your preferred locale ...