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How to format a string as a telephone number in C#

I have a string "1112224444' it is a telephone number. I want to format as 111-222-4444 before I store it in a file. It is on a datarecord and I would prefer to be able to do this without assigning a new variable. ...
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Are tuples more efficient than lists in Python?

...s are incorporated directly in a tuple object. In contrast, lists have an extra layer of indirection to an external array of pointers. This gives tuples a small speed advantage for indexed lookups and unpacking: $ python3.6 -m timeit -s 'a = (10, 20, 30)' 'a[1]' 10000000 loops, best of 3: 0.0304 ...
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RandomForestClassifier vs ExtraTreesClassifier in scikit learn

Can anyone explain the difference between the RandomForestClassifier and ExtraTreesClassifier in scikit learn. I've spent a good bit of time reading the paper: ...
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insert a NOT NULL column to an existing table

... supplied into the existing rows (i.e. 0.0 for float, 0 for integer, empty string for string, etc). – Michael Tsang Sep 18 '19 at 15:17 add a comment  |  ...
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How to stop flask application without using ctrl-c

...sn't accepted, but it seems to be the cleanest and works great without any extra dependencies. Thanks so much. – Eric Reed Jul 22 at 21:41 add a comment  | ...
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How to convert Set to String[]?

I need to get a String[] out of a Set<String> , but I don't know how to do it. The following fails: 7 Answers ...
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Passing functions with arguments to another function in Python?

...o do this. My favorite way is using lambda because it avoids dependency on extra package and is the least verbose. Assume you have a function add(x, y) and you want to pass add(3, y) to some other function as parameter such that the other function decides the value for y. Use lambda # generic func...
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C# 5 async CTP: why is internal “state” set to 0 in generated code before EndAwait call?

...rrect, as -1 normally means "finished". I could argue that we're giving an extra meaning to state 0 at the moment, but ultimately it doesn't really matter. The point of this question was finding out why the state is being set at all. The value is relevant if the await ends in an exception which is ...
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Replace one substring for another string in shell script

... To replace the first occurrence of a pattern with a given string, use ${parameter/pattern/string}: #!/bin/bash firstString="I love Suzi and Marry" secondString="Sara" echo "${firstString/Suzi/$secondString}" # prints 'I love Sara and Marry' To replace all occurrences, use ${p...
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What's the recommended approach to resetting migration history using Django South?

...t a longer variant of manage.py convert_to_south my_app, but I prefer that extra control, in such delicate situation as modifying the production database. share | improve this answer | ...