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Downloading a large file using curl
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I tested it with a https, works great!!!, Thanks for you help @dynamic.
– Ozal Zarbaliyev
Jan 15 '19 at 13:14
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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
...pply is generally not much faster than iterating over a Python list. Let's test the performance of a for-loop to do the same thing as above
%%timeit
A1, A2 = [], []
for val in df['a']:
A1.append(val**2)
A2.append(val**3)
df['A1'] = A1
df['A2'] = A2
298 ms ± 7.14 ms per loop (mean ± std....
Tools to selectively Copy HTML+CSS+JS From A Specific Element of DOM [closed]
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Holy crap that is awesome. Can confirm @xoofx 's findings that the HTML markup remains the same but wanted to comment further that it also outputs skeleton parent wrapping elements needed to truly match the style.
– Daniel Sokolowski
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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
...y verbose, but functional.
import pandas as pd
import numpy as np
# Some test data frame
df = pd.DataFrame({'num_legs': [2, 4, np.nan, 0, np.nan],
'num_wings': [2, 0, np.nan, 0, 9],
'num_specimen_seen': [10, np.nan, 1, 8, np.nan]...
How does having a dynamic variable affect performance?
...on time)
Using a dynamically-generated method that gets created before the test.
Using a dynamically-generated method that gets lazily instantiated during the test.
Each gets called 1 million times in a simple loop. Here are the timing results:
Direct: 3.4248ms
Dynamic: 45.0728ms
Reflection: 888.4...
How to use transactions with dapper.net?
...action . For example it can be used to great effect when unit/integration testing code that does database calls where you want to roll back after. Just float a TransactionScope, test the code, and dispose during test cleanup.
– Larry Smith
Nov 14 '17 at 21:04...
jquery append to front/top of list
...er">Goodbye</div>
</div>
$('.container').prepend('<p>Test</p>');
refer http://api.jquery.com/prepend/ for more info.
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Multiple queries executed in java in single statement
...rejected at runtime with an SQLException.
String dbUrl = "jdbc:mysql:///test?allowMultiQueries=true";
Unless such instruction is passed, an SQLException is thrown.
You have to use execute( String sql ) or its other variants to fetch results of the query execution.
boolean hasMoreResultSet...
Why does this C++ snippet compile (non-void function does not return a value) [duplicate]
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@dpassage confirmed that it was being optimized out.
– Shafik Yaghmour
Dec 17 '13 at 2:38
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Automapper - how to map to constructor parameters instead of property setters
...rg1, etc));
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using AutoMapper;
using NUnit.Framework;
namespace UnitTests
{
[TestFixture]
public class Tester
{
[Test]
public void Test_ConstructUsing()
{
Mapper.CreateMap<ObjectFrom, ObjectTo>()
.ConstructUsing(x => new...