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What is the correct way to make a custom .NET Exception serializable?
More specifically, when the exception contains custom objects which may or may not themselves be serializable.
7 Answers
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What is the purpose of “return await” in C#?
...n async method behave differently: when combined with using (or, more generally, any return await in a try block).
Consider these two versions of a method:
Task<SomeResult> DoSomethingAsync()
{
using (var foo = new Foo())
{
return foo.DoAnotherThingAsync();
}
}
async Tas...
Compare two DataFrames and output their differences side-by-side
...original question
The first step is to concatenate the DataFrames horizontally with the concat function and distinguish each frame with the keys parameter:
df_all = pd.concat([df.set_index('id'), df2.set_index('id')],
axis='columns', keys=['First', 'Second'])
df_all
It's pr...
Python Pandas merge only certain columns
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You can use .loc to select the specific columns with all rows and then pull that. An example is below:
pandas.merge(dataframe1, dataframe2.iloc[:, [0:5]], how='left', on='key')
In this example, you are merging dataframe1 and dataframe2. You have chosen to do an outer left jo...
Easy idiomatic way to define Ordering for a simple case class
...[...] to Ordered[TupleN[...]] provided an implicit Ordering[TN] exists for all elements T1, ..., TN of the tuple, which should always be the case because it makes no sense to sort on a data type with no Ordering.
The implicit ordering for Tuples is your go-to for any sorting scenario involving a co...
What's the difference between eval, exec, and compile?
...
The short answer, or TL;DR
Basically, eval is used to evaluate a single dynamically generated Python expression, and exec is used to execute dynamically generated Python code only for its side effects.
eval and exec have these two differences:
eval accep...
How to dump a dict to a json file?
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you can supply all those parameters to dump(sample, file, ...) too. The extra step of writing to a string is not needed. dump internally writes in chunks. This could be more efficient than to compile a (possibly huge) string first.
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Saving image from PHP URL
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If you have allow_url_fopen set to true:
$url = 'http://example.com/image.php';
$img = '/my/folder/flower.gif';
file_put_contents($img, file_get_contents($url));
Else use cURL:
$ch = curl_init('http://example.com/image.php');
$fp = f...
Python - 'ascii' codec can't decode byte
I'm really confused. I tried to encode but the error said can't decode... .
7 Answers
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How do I run msbuild from the command line using Windows SDK 7.1?
I'm setting up .NET 4.0 support on our CI server. I've installed .NET 4.0, and the .NET tools from the Windows 7.1 SDK.
7 A...