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Select DISTINCT individual columns in django?
I'm curious if there's any way to do a query in Django that's not a " SELECT * FROM... " underneath. I'm trying to do a " SELECT DISTINCT columnName FROM ... " instead.
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jQuery UI DatePicker - Change Date Format
...orKnowledge just use y. datepicker-formatting
– Shadoath
Mar 24 '15 at 17:08
11
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Read only the first line of a file?
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Use the .readline() method (Python 2 docs, Python 3 docs):
with open('myfile.txt') as f:
first_line = f.readline()
Some notes:
As noted in the docs, unless it is the only line in the file, the string returned from f.readline() will contain a trailing ne...
How to get a value from a cell of a dataframe?
... @Sophologist I agree that its ridiculous that this is required. It also does not work when you try to pass the conditionals inline; my_df.loc[my_df['Col1'] == foo]['Col2'] still returns an object of type <class 'pandas.core.series.Series'>
– user5359531
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Create timestamp variable in bash script
...Define a timestamp function
timestamp() {
date +"%T" # current time
}
# do something...
timestamp # print timestamp
# do something else...
timestamp # print another timestamp
# continue...
If you don't like the format given by the %T specifier you can combine the other time conversion specifiers...
Maven dependency for Servlet 3.0 API?
...t;Repository hosting the jee6 artifacts</name>
<url>http://download.java.net/maven/2</url>
</repository>
</repositories>
<dependencies>
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-web-api</artifactId&...
Access-Control-Allow-Origin wildcard subdomains, ports and protocols
I'm trying to enable CORS for all subdomains, ports and protocol.
11 Answers
11
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Representing graphs (data structure) in Python
...dict(tuples)) will be fast but also memory efficient? One must be able to do various graph operations on it.
As pointed out, the various graph representations might help. How does one go about implementing them in Python? As for the libraries, this question has quite good answers.
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深入理解 x86/x64 的中断体系 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
... IDTR.base 的值，这意味着 IVT 在 0 的位置上，典型的如： DOS 操作系统。
在保护模式下 IDTR.base 将向不再是中断向量表，而是中断描述符表。不再称为 IVT 而是 IDT。那是因为：
在实模式下，DITR.base 指向的表格项直接给出中断服...
Is background-color:none valid CSS?
...ited Oct 13 '16 at 16:24
JGallardo
9,28666 gold badges7171 silver badges8080 bronze badges
answered Jan 5 '12 at 8:42
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