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How to find the length of a string in R
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See ?nchar. For example:
> nchar("foo")
[1] 3
> set.seed(10)
> strn <- paste(sample(LETTERS, 10), collapse = "")
> strn
[1] "NHKPBEFTLY"
> nchar(strn)
[1] 10
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Can a for loop increment/decrement by more than one?
...in Javascript besides i++ and ++i ? For example, I want to increment by 3 instead of one.
7 Answers
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Convert a list to a dictionary in Python
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from itertools import izip
i = iter(a)
b = dict(izip(i, i))
In Python 3 you could also use a dict comprehension, but ironically I think the simplest way to do it will be with range() and len(), which would normally be a code smell.
b = {a[i]: a[i+1] for i in range(0, len(a), 2)}
So the iter(...
Swift 编程语言入门教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...教程，分享给大家
原文地址：http://gashero.iteye.com/blog/2075324
目录
1 简介
2 Swift入门
3 简单值
4 控制流
5 函数与闭包
6 对象与类
7 枚举与结构
1 简介
今天凌晨Apple刚刚发布了Swift编程语言，本文从其发布...
Find Oracle JDBC driver in Maven repository
...pId>
<artifactId>ojdbc14</artifactId>
<version>10.2.0.3.0</version>
...and the URL to download the file which in this case is
http://www.oracle.com/technology/software/tech/java/sqlj_jdbc/index.html.
Once you've downloaded the JAR just add it to your computer repository...
proper hibernate annotation for byte[]
I have an application using hibernate 3.1 and JPA annotations. It has a few objects with byte[] attributes (1k - 200k in size). It uses the JPA @Lob annotation, and hibernate 3.1 can read these just fine on all major databases -- it seems to hide the JDBC Blob vendor peculiarities (as it should do...
How to merge 2 JSON objects from 2 files using jq?
...les in the same array.
Would get you:
{
"value1": 200,
"timestamp": 1382461861,
"value": {
"aaa": {
"value1": "v1",
"value2": "v2",
"value3": "v3",
"value4": 4
},
"bbb": {
"value1": "v1",
"value2": "v2",
"value3": "v3"
},
"ccc": {...
How do I modify fields inside the new PostgreSQL JSON datatype?
With postgresql 9.3 I can SELECT specific fields of a JSON data type, but how do you modify them using UPDATE? I can't find any examples of this in the postgresql documentation, or anywhere online. I have tried the obvious:
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How do I base64 encode (decode) in C?
..., 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3',
'4', '5', '6', '7', '8', '9', '+', '/'};
static char *decoding_table = NULL;
static int mod_table[] = {0, 2, 1};
char *base64_encode(const unsigned char *data,
size_t ...
How to convert int to char with leading zeros?
...as varchar(5)), 5)
It will get the result in 5 digits, ex: 00001,...., 01234
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