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passing several arguments to FUN of lapply (and others *apply)
I have a question regarding passing multiple arguments to a function, when using lapply in R .
4 Answers
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Detect if value is number in MySQL
...l1 * 1) = col1
It doesn't work for non-standard numbers like
1e4
1.2e5
123. (trailing decimal)
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C++ performance challenge: integer to std::string conversion
...
Ah, awesome challenge by the way... I've had a lot of fun with this.
I have two algorithms to submit (code is at the bottom if you feel like skipping to it). In my comparisons I require that the function return a string and that it can handle int and unsigned int. Comparing thi...
App Inventor 2 CustomWebView 拓展：高级版Web浏览器，完美浏览现代Web前...
...url的页面，这款拓展统统解决。
.aix 拓展下载：
cn.fun123.CustomWebView.aix
基础使用方法：
例如，使用此拓展访问 react 写的网页，效果如下：
而使用原生的Web浏览器则无法访问：
属性
AdHosts
Sets the ...
How to compile a static library in Linux?
...e lib
#include <stdio.h>
#include "lib.h"
int main ( void )
{
fun1(10);
fun2(10);
return 0;
}
lib.h the libs main header
#ifndef LIB_H_INCLUDED
#define LIB_H_INCLUDED
#include "lib1.h"
#include "lib2.h"
#endif
lib1.c first lib source
#include "lib1.h"
#include <stdio...
Is there a way to pass optional parameters to a function?
Is there a way in Python to pass optional parameters to a function while calling it and in the function definition have some code based on "only if the optional parameter is passed"
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使用Activity启动器组件 · App Inventor 2 中文网
...页，例如，
Action：android.intent.action.VIEW
DataUri：https://www.fun123.cn
使用预先指定的消息启动邮件程序
2020 年 1 月 26 日：此示例已更新以适应 android 中的更改。 此处显示的电子邮件发送代码将在下一个应用程序...
MySQL Conditional Insert
...nsert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = 123
AND item = 456)
In this, dual is a table with one row only (found orig...
Reading binary file and looping over each byte
... example uses a chunksize of 8192 Bytes. The parameter for the file.read()-function simply specifies the size, i.e. the number of Bytes to be read. codeape chose 8192 Byte = 8 kB (actually it's KiB but that's not as commonly known). The value is "totally" random but 8 kB seems to be an appropriate v...