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Get last result in interactive Python shell
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Just for the record, ipython takes this one step further and you can access every result with _ and its numeric value
In [1]: 10
Out[1]: 10
In [2]: 32
Out[2]: 32
In [3]: _
Out[3]: 32
In [4]: _1
Out[4]: 10
In [5]: _2
Out[5]: 32
In [6]: _1 + _2
Out[6]: 42
In [7]: _6
Out[7]: 42...
How does the bitwise complement operator (~ tilde) work?
...representation of a number, taking its complement (inverting all the bits) and adding one. Two starts as 0000 0010, and by inverting the bits we get 1111 1101. Adding one gets us the result above. The first bit is the sign bit, implying a negative.
So let's take a look at how we get ~2 = -3:
Here's ...
How do I kill background processes / jobs when my shell script exits?
... kill $(jobs -p) doesn't work in dash, because it executes command substitution in a subshell (see Command Substitution in man dash)
– user1431317
Jun 15 '17 at 13:37
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How do I use cascade delete with SQL Server?
I have 2 tables: T1 and T2, they are existing tables with data. We have a one to many relationship between T1 and T2. How do I alter the table definitions to perform cascading delete in SQL Server when a record from T1 is deleted, all associated records in T2 also deleted.
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Python name mangling
... for sure a controversial way of doing things. Python newbies just hate it and even some old Python guys despise this default - but it is the default anyway, so I really recommend you to follow it, even if you feel uncomfortable.
If you really want to send the message "Can't touch this!" to your us...
How do you post to an iframe?
...ut if you're using ordinary HTML markup, you're fine. The target attribute and frame names isn't some clever ninja hack; although it was deprecated (and therefore won't validate) in HTML 4 Strict or XHTML 1 Strict, it's been part of HTML since 3.2, it's formally part of HTML5, and it works in just a...
Generate array of all letters and digits
Using ruby, is it possible to make an array of each letter in the alphabet and 0-9 easily?
7 Answers
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“ImportError: No module named” when trying to run Python script
...t. I get a ImportError: No module named ..., however, if I launch ipython and import the same module in the same way through the interpreter, the module is accepted.
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Postgres: clear entire database before re-creating / re-populating from bash script
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I'd just drop the database and then re-create it. On a UNIX or Linux system, that should do it:
$ dropdb development_db_name
$ createdb developmnent_db_name
That's how I do it, actually.
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中文网（自研/维护）拓展 · App Inventor 2 中文网
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事件
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方法
RandomNumCode(length)
返回一个指定位数随机数字码。
SendSms(phoneNumber,signName,templateCode,templateParam)
发送短信。参数：手机号，签名名称，模板CODE，模板参数JSON
Clie...