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Removing double quotes from variables in batch file creates problems with CMD environment
...uotes ' do the following:
set widget=%widget:"='%
Note: To replace the word "World" (not case sensitive) with BobB do the following:
set widget="Hello World!"
set widget=%widget:world=BobB%
set widget
Output:
widget="Hello BobB!"
As far as your initial question goes (save the following code...
How to subtract X days from a date using Java calendar?
...
Taken from the docs here:
Adds or subtracts the specified amount of time to the given calendar field, based on the calendar's rules. For example, to subtract 5 days from the current time of the calendar, you can achieve it by calling:
Calendar calendar = ...
Compare double to zero using epsilon
...00 00000000 00000000 00000000 00000000 00000001 × 2^0 = 1 + 2^-52
Therefore:
epsilon = (1 + 2^-52) - 1 = 2^-52
Are there any numbers between 0 and epsilon? Plenty... E.g. the minimal positive representable (normal) number is:
1.0000 00000000 00000000 00000000 00000000 00000000 00000000 × 2^-...
What is the purpose of the “role” attribute in HTML?
I keep seeing role attributes in some people's work. I use it too, but I'm not sure about its effect.
5 Answers
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Difference between SPI and API?
...l.
Put differently, the API tells you what a specific class/method does for you, and the SPI tells you what you must do to conform.
Usually API and SPI are separate. For example, in JDBC the Driver class is part of the SPI: If you simply want to use JDBC, you don't need to use it directly, but ev...
Is Javascript a Functional Programming Language?
... because functions are first class objects, there are closures, and higher order functions, does Javascript deserve to be called a Functional Programming language? The main thing I think it lacks is Pure Functions, and it doesn't 'feel' like other functional languages, like lisp (although thats not...
Why can't I use switch statement on a String?
...a SE 7, at least 16 years after they were first requested. A clear reason for the delay was not provided, but it likely had to do with performance.
Implementation in JDK 7
The feature has now been implemented in javac with a "de-sugaring" process; a clean, high-level syntax using String constants ...
What does [object Object] mean?
...n the comments, you should use the tools included in browsers like Firefox or Chrome to introspect objects by doing console.log(whichIsVisible()) instead of alert.
Sidenote: IDs should not start with digits.
share
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Showing data values on stacked bar chart in ggplot2
... 0.5) in geom_text.
ggplot(Data, aes(x = Year, y = Frequency, fill = Category, label = Frequency)) +
geom_bar(stat = "identity") +
geom_text(size = 3, position = position_stack(vjust = 0.5))
Also note that "position_stack() and position_fill() now stack values in the reverse order of the gr...
ProcessBuilder: Forwarding stdout and stderr of started processes without blocking the main thread
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To only way in Java 6 or earlier is with a so called StreamGobbler (which you are started to create):
StreamGobbler errorGobbler = new StreamGobbler(p.getErrorStream(), "ERROR");
// any output?
StreamGobbler outputGobbler = new StreamGobbler(p.g...