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Starting python debugger automatically on error

... You can use traceback.print_exc to print the exceptions traceback. Then use sys.exc_info to extract the traceback and finally call pdb.post_mortem with that traceback import pdb, traceback, sys def bombs(): a = [] print a[0] if __name__ == '...
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How to convert vector to array

...? If you're calling an API function that expects the former, you can do do_something(&v[0], v.size()), where v is a vector of doubles. The elements of a vector are contiguous. Otherwise, you just have to copy each element: double arr[100]; std::copy(v.begin(), v.end(), arr); Ensure not only...
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What do *args and **kwargs mean? [duplicate]

...ments, no matter how many you supply, you could write it like this: def my_sum(*args): return sum(args) It’s probably more commonly used in object-oriented programming, when you’re overriding a function, and want to call the original function with whatever arguments the user passes in. Y...
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Casting vs using the 'as' keyword in the CLR

...bject obj) cil managed { // Code size 22 (0x16) .maxstack 8 IL_0000: ldarg.1 IL_0001: isinst MyClass IL_0006: brfalse.s IL_0015 IL_0008: ldarg.1 IL_0009: castclass MyClass IL_000e: pop IL_000f: ldarg.1 IL_0010: call void [mscorlib]System.Console::WriteL...
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using lodash .groupBy. how to add your own keys for grouped output?

...ame": "eddie", "color": "green", "age": "77" }]; console.log( _.chain(data) // Group the elements of Array based on `color` property .groupBy("color") // `key` is group's name (color), `value` is the array of objects .map((value, key) => ({ color: key, users: valu...
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Any gotchas using unicode_literals in Python 2.6?

...ng: utf-8 name = 'helló wörld from two' one.py # encoding: utf-8 from __future__ import unicode_literals import two name = 'helló wörld from one' print name + two.name The output of running python one.py is: Traceback (most recent call last): File "one.py", line 5, in <module> ...
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App Inventor 2 时间处理教程 - 时间戳转换、格式化与计算 · App Inventor 2 中文网

... = 计时器1.FormatDateTime(当前时间, "yyyy-MM-dd HH:mm:ss") 标签_时间.Text = 显示 } 实时更新 when Screen1.Initialize() { 计时器1.TimerInterval = 1000 // 1秒更新 计时器1.TimerEnabled = true } when 计时器1.Timer() { var 当前时间 = 计...
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Arduino 101 实验05 - 光照传感器,做一个自动小夜灯 · App Inventor 2 中文网

...1 LED D5 5 固件:.ino 里把 LIGHT_SENSOR 和 LED 都设为 ENABLED,其余 DISABLED。 这一篇要同时用两个模块,是唯一需要开两项的实验。其余实验按各自篇里说的只开一项。 三、界面组件 ...
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Is there a REAL performance difference between INT and VARCHAR primary keys?

...(think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables. 14 ...
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How to limit the maximum value of a numeric field in a Django model?

...go.db import models class IntegerRangeField(models.IntegerField): def __init__(self, verbose_name=None, name=None, min_value=None, max_value=None, **kwargs): self.min_value, self.max_value = min_value, max_value models.IntegerField.__init__(self, verbose_name, name, **kwargs) ...