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How to force R to use a specified factor level as reference in a regression?
...
See the relevel() function. Here is an example:
set.seed(123)
x <- rnorm(100)
DF <- data.frame(x = x,
y = 4 + (1.5*x) + rnorm(100, sd = 2),
b = gl(5, 20))
head(DF)
str(DF)
m1 <- lm(y ~ x + b, data = DF)
summary(m1)
Now alter the factor ...
How to get a list of installed android applications and pick one to run
...ng with a server. Is there any guidelines?
– dowjones123
Jun 30 '15 at 20:07
1
@dowjones123 Did u...
Fastest check if row exists in PostgreSQL
...
How about simply:
select 1 from tbl where userid = 123 limit 1;
where 123 is the userid of the batch that you're about to insert.
The above query will return either an empty set or a single row, depending on whether there are records with the given userid.
If this turns o...
linux svn搭建配置及svn命令详解 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...asswd
[users]
# harry = harryssecret
# sally = sallyssecret
hello=123
用户名=密码
这样我们就建立了hello用户， 123密码
2.2 再设置权限authz
[root@www ~]# vi authz
[/]
hello= rw
意思是hello用户对所有的目录有读写权限，当然也...
Several ports (8005, 8080, 8009) required by Tomcat Server at localhost are already in use
...st gives me the help for the kill command.
– CoderGuy123
Jun 1 '15 at 2:18
...
Insert all values of a table into another table in SQL
...dited Feb 26 '14 at 1:12
hichris123
9,5151212 gold badges5050 silver badges6666 bronze badges
answered Apr 21 '10 at 9:35
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How do I properly escape quotes inside HTML attributes?
...gh, try <option value='<?php echo htmlentities("' onmouseover='alert(123);' foo='"); ?>' /> - make sure you use it with ENT_QUOTES, this is safe: <option value='<?php echo htmlentities("' onmouseover='alert(123);' foo='", ENT_QUOTES); ?>' /> , but in addition to ENT_QUOTES y...
How to remove the hash from window.location (URL) with JavaScript without page refresh?
...
This will remove the trailing hash as well.
eg: http://test.com/123#abc -> http://test.com/123
if(window.history.pushState) {
window.history.pushState('', '/', window.location.pathname)
} else {
window.location.hash = '';
}
...
“Variable” variables in Javascript?
... try using eval():
var data = "testVariable";
eval("var temp_" + data + "=123;");
alert(temp_testVariable);
Or using the window object:
var data = "testVariable";
window["temp_" + data] = 123;
alert(window["temp_" + data]);
http://www.hiteshagrawal.com/javascript/dynamic-variables-in-javascrip...
Easiest way to compare arrays in C#
...or tuples via using StructuralComparisons type:
object[] a1 = { "string", 123, true };
object[] a2 = { "string", 123, true };
Console.WriteLine (a1 == a2); // False (because arrays is reference types)
Console.WriteLine (a1.Equals (a2)); // False (because arrays is reference types)
IStruct...