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delete_all vs destroy_all?
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80
It should also be noted that 1) Callbacks are not called when using delete_all, and 2) destroy_all instantiates all the records and destroys...
How to get thread id from a thread pool?
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answered Jul 20 '10 at 20:59
skaffmanskaffman
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Printf width specifier to maintain precision of floating-point value
...n:
#include <float.h>
int Digs = DECIMAL_DIG;
double OneSeventh = 1.0/7.0;
printf("%.*e\n", Digs, OneSeventh);
// 1.428571428571428492127e-01
But let's dig deeper ...
Mathematically, the answer is "0.142857 142857 142857 ...", but we are using finite precision floating point numbers.
Let...
MySQL remove all whitespaces from the entire column
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203
To replace all spaces :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, ' ', '')
To remo...
How to force IntelliJ IDEA to reload dependencies from build.sbt after they changed?
...t)
– Kaushik Acharya
Nov 16 '16 at 10:46
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How can I test that a value is “greater than or equal to” in Jasmine?
I want to confirm that a value is a decimal (or 0), so the number should be greater than or equal to zero and less than 1.
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How do you clear a slice in Go?
...definition of 'clear'. One of the valid ones certainly is:
slice = slice[:0]
But there's a catch. If slice elements are of type T:
var slice []T
then enforcing len(slice) to be zero, by the above "trick", doesn't make any element of
slice[:cap(slice)]
eligible for garbage collection. This ...
Add missing dates to pandas dataframe
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270
You could use Series.reindex:
import pandas as pd
idx = pd.date_range('09-01-2013', '09-30-201...
Awk学习笔记 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...达式元字符
8. POSIX字符集
9. 匹配操作符(~)
10. 比较表达式
11. 范围模板
12. 一个验证passwd文件有效性的例子
13. 几个实例
14. awk编程
14.1. 变量
14.2. BEGIN模块
14.3. END模块
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What is the difference between “px”, “dip”, “dp” and “sp”?
...sed on the physical density of the screen. These units are relative to a 160
dpi screen, so one dp is one pixel on a 160 dpi screen. The ratio of
dp-to-pixel will change with the screen density, but not necessarily
in direct proportion. Note: The compiler accepts both "dip" and
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