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How can I write output from a unit test?
Any call in my unit tests to either Debug.Write(line) or Console.Write(Line) simply gets skipped over while debugging and the output is never printed. Calls to these functions from within classes I'm using work fine.
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Trimming a huge (3.5 GB) csv file to read into R
... expert at this, but you might consider trying MapReduce, which would basically mean taking a "divide and conquer" approach. R has several options for this, including:
mapReduce (pure R)
RHIPE (which uses Hadoop); see example 6.2.2 in the documentation for an example of subsetting files
Alterna...
Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
...igure out what's happening. I have a Card entity which contains Sides (usually 2) - and both Cards and Sides have a Stage. I'm using EF Codefirst migrations and the migrations are failing with this error:
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How to slice an array in Bash
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There is also a convenient shortcut to get all elements of the array starting with specified index. For example "${A[@]:1}" would be the "tail" of the array, that is the array without its first element.
version=4.7.1
A=( ${version//\./ } )
echo "${A[@]}" # 4 7 1
B...
what is reverse() in Django
...!-- django <= 1.4 -->
<a href="{% url url_name %}">link which calls some_view</a>
<!-- django >= 1.5 or with {% load url from future %} in your template -->
<a href="{% url 'url_name' %}">link which calls some_view</a>
This will be rendered as:
<a href="...
error C2664: “std::list::list(const std::allocator &)”: 不能将参数 1...
...转换为“const std::allocator &”错误日志：error C2664: std::list<_Ty>::list(const std::allocator<_Ty> &): 不能将参数 1 从std::vector<_Ty>转换为const std::...错误日志：
error C2664: “std::list<_Ty>::list(const std::allocator<_Ty> &)”: 不能将参数 1 从
“std::vect...
Cannot overwrite model once compiled Mongoose
...y have a schema defined, and then you are defining the schema again. Generally what you should do is instantiate the schema once, and then have a global object call it when it needs it.
For example:
user_model.js
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var userSchema...
django: BooleanField, how to set the default value to true?
...mentary to it.
– Josh Brown
May 30 '15 at 22:31
This only works for form model fields. Also, changing the model defaul...
Get generated id after insert
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PHPDevPHPDev
7155 bronze badges
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Unique fields that allow nulls in Django
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155
Django has not considered NULL to be equal to NULL for the purpose of uniqueness checks since ...