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Transpose a data frame
...ile the name column is in it - all numeric values will then be turned into strings!
Here's a solution that keeps numbers as numbers:
# first remember the names
n <- df.aree$name
# transpose all but the first column (name)
df.aree <- as.data.frame(t(df.aree[,-1]))
colnames(df.aree) <- n
d...
Can someone explain __all__ in Python?
...xplicitly mentioned here, is exactly when __all__ is used. It is a list of strings defining what symbols in a module will be exported when from <module> import * is used on the module.
For example, the following code in a foo.py explicitly exports the symbols bar and baz:
__all__ = ['bar', '...
Java / Android - How to print out a full stack trace?
...
There's overrides of all the log methods with (String tag, String msg, Throwable tr) signatures.
Passing an exception as the third parameter should give you the full stacktrace in logcat.
share
...
How can I wrap or break long text/word in a fixed width span?
...t;lgasdfjksdajgdsglkgsadfasdfadfasdfadsfasdfasddkgjk</span> , a long string of non-spaced text, the word(s) break or wrap to next line.
...
Check time difference in Javascript
...8800000 => hh = 8, mm = 0, ss = 0, msec = 0
You can convert time as string to 24-hour format like this:
function parseTime(s) {
var part = s.match(/(\d+):(\d+)(?: )?(am|pm)?/i);
var hh = parseInt(part[1], 10);
var mm = parseInt(part[2], 10);
var ap = part[3] ? part[3].toUpper...
Calling a function of a module by using its name (a string)
What is the best way to go about calling a function given a string with the function's name in a Python program. For example, let's say that I have a module foo , and I have a string whose content is "bar" . What is the best way to call foo.bar() ?
...
How to use double or single brackets, parentheses, curly braces
...$default}
hello
and several more
Also, brace expansions create lists of strings which are typically iterated over in loops:
$ echo f{oo,ee,a}d
food feed fad
$ mv error.log{,.OLD}
(error.log is renamed to error.log.OLD because the brace expression
expands to "mv error.log error.log.OLD")
$ for ...
Expansion of variables inside single quotes in a command in Bash
...relevant: Which characters need to be escaped in bash?
Do not concatenate strings interpreted by a shell
You should absolutely avoid building shell commands by concatenating variables. This is a bad idea similar to concatenation of SQL fragments (SQL injection!).
Usually it is possible to have pl...
How to check if a map contains a key in Go?
... the value of "foo" from the map or a "zero value" (in this case the empty string) and ok will receive a bool that will be set to true if "foo" was actually present in the map
evaluates ok, which will be true if "foo" was in the map
If "foo" is indeed present in the map, the body of the if stateme...
How to bundle a native library and a JNI library inside a JAR?
...m.load(File) to load the library instead of the typical System.loadLibrary(String) which searches the java.library.path system property. This method makes installation much simpler as the user does not have to install the JNI library on his system, at the expense, however, that all platforms might n...