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How do I get the row count of a pandas DataFrame?
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You can use the .shape property or just len(DataFrame.index). However, there are notable performance differences ( len(DataFrame.index) is fastest).
Code to reproduce the plot:
import numpy as np
import pandas as pd
import perfplot
perfplot.save(
"out.png",
setup=lam...
Getting a list item by index
...g c# moving over from Java. I can't seem to find how to get a list item by index. In java to get the first item of the list it would be:
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Callback after all asynchronous forEach callbacks are completed
...sole.log('all done'); }
var itemsProcessed = 0;
[1, 2, 3].forEach((item, index, array) => {
asyncFunction(item, () => {
itemsProcessed++;
if(itemsProcessed === array.length) {
callback();
}
});
});
(thanks to @vanuan and others) This approach guarantees that all items...
Numpy index slice without losing dimension information
I'm using numpy and want to index a row without losing the dimension information.
6 Answers
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mongoDB/mongoose: unique if not null
...s without the field by setting the sparse option to true when defining the index. As in:
email : {type: String, trim: true, index: true, unique: true, sparse: true}
Or in the shell:
db.users.ensureIndex({email: 1}, {unique: true, sparse: true});
Note that a unique, sparse index still does not...
How to override and extend basic Django admin templates?
How do I override an admin template (e.g. admin/index.html) while at the same time extending it (see https://docs.djangoproject.com/en/dev/ref/contrib/admin/#overriding-vs-replacing-an-admin-template )?
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Avoiding if statement inside a for loop?
...lt;vector>
template <typename Container, typename Functor, typename Index = std::size_t>
void for_each_indexed(const Container& c, Functor f, Index index = 0) {
for (const auto& e : c)
f(index++, e);
}
int main() {
using namespace std;
set<char> s{'b',...
Regex: match everything but specific pattern
... everything but a string starting with a specific pattern (specifically index.php and what follows, like index.php?id=2342343 )
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Pandas: drop a level from a multi-level column index?
If I've got a multi-level column index:
7 Answers
7
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CSS I want a div to be on top of everything
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In order for z-index to work, you'll need to give the element a position:absolute or a position:relative property. Once you do that, your links will function properly, though you may have to tweak your CSS a bit afterwards.
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