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What does it mean in shell when we put a command inside dollar sign and parentheses: $(command)
...rname $(which gcc)))/lib using back quotes. Even before you get into the difficulties of doing it in Markdown, it is harder because you have to escape the backquotes of the nested commands, whereas you don't with the $(...) notation.
– Jonathan Leffler
Aug 1 '...
Java regular expression OR operator
...t.println(s.replaceAll("string(1|2)", "blah"));
has the same output. but if you just do this:
String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|2", "blah"));
you get:
blah, stringblah, string3
because you've said "string1" or "2".
If you don't want to capture ...
Omit rows containing specific column of NA
...c("y", "z"))
# x y z
# 2 2 10 33
EDIT: Only return rows with no NAs
If you want to eliminate all rows with at least one NA in any column, just use the complete.cases function straight up:
DF[complete.cases(DF), ]
# x y z
# 2 2 10 33
Or if completeFun is already ingrained in your workfl...
Why does substring slicing with index out of range work?
...
You're correct! 'example'[3:4] and 'example'[3] are fundamentally different, and slicing outside the bounds of a sequence (at least for built-ins) doesn't cause an error.
It might be surprising at first, but it makes sense when you think about it. Indexing returns a single item, but slicin...
Difference between -pthread and -lpthread while compiling
What is the difference between gcc -pthread and gcc -lpthread which is used while compiling multithreaded programs?
3 A...
Getting value of select (dropdown) before change
...
I don't agree with this solution. If you change the value once it will work but if you do it one more time it won't. You have to click somewhere to loose focus and another click on the dropdown. I suggest: $("#dropdownId").on('change', function () { ...
How to execute a java .class from the command line
...ory is not in your classpath ( where java looks for .class definitions )
If that's the case and listing the contents of your dir displays:
Echo.java
Echo.class
Then any of this may work:
java -cp . Echo "hello"
or
SET CLASSPATH=%CLASSPATH;.
java Echo "hello"
And later as Fredrik point...
Download JSON object as a file from browser
... dataStr = "data:text/json;charset=utf-8," + encodeURIComponent(JSON.stringify(storageObj));
var dlAnchorElem = document.getElementById('downloadAnchorElem');
dlAnchorElem.setAttribute("href", dataStr );
dlAnchorElem.setAttribute("download", "scene.json");
dlAnchorElem.click();
In this cas...
Change the image source on rollover using jQuery
...on() {
var src = $(this).attr("src").match(/[^\.]+/) + "over.gif";
$(this).attr("src", src);
})
.mouseout(function() {
var src = $(this).attr("src").replace("over.gif", ".gif");
$(this).attr("src", src);
});
});
For those tha...
comparing sbt and Gradle [closed]
...
Note that one key difference between SBT and Gradle is its dependency management:
SBT: Ivy, with a a revision which can be given as a fixed one (1.5.2, for instance) or as latest (or dynamic) one.
See "Ivy Dependency"
That means the "-SNAPSHOT...