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How to convert a char array to a string?
...e we will lose some data. The possible solution is:
cout << string("123\0 123") << endl;
cout << string("123\0 123", 8) << endl;
Output is:
123
123 123
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impr...
Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
...
parseInt vs unary plus, when to use which?
... '~~x',
'x>>>0',
'isNaN(x)'
];
VALUES = [
'"123"',
'"+123"',
'"-123"',
'"123.45"',
'"-123.45"',
'"12e5"',
'"12e-5"',
'"0123"',
'"0000123"',
'"0b111"',
'"0o10"',
'"0xBABE"',
'"4294967295"',
'"1...
An example of how to use getopts in bash
...pecify strength, either 45 or 90.
h | *) # Display help.
$ ./foo.sh -s 123 -p any_string
Strength needs to be either 45 or 90, 123 found instead.
p is any_string
$ ./foo.sh -s 90 -p any_string
Strength is 90.
p is any_string
See: Small getopts tutorial at Bash Hackers Wiki
...
Ruby, remove last N characters from a string?
...diomatic (and I'd argue, even more readable than other answers here):
'abc123'.delete_suffix('123') # => "abc"
'abc123'.delete_suffix!('123') # => "abc"
It's even significantly faster (almost 40% with the bang method) than the top answer. Here's the result of the same benchmark:
...
How can I convert a string to a number in Perl?
...
This is a simple solution:
Example 1
my $var1 = "123abc";
print $var1 + 0;
Result
123
Example 2
my $var2 = "abc123";
print $var2 + 0;
Result
0
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improve thi...
Removing all non-numeric characters from string in Python
... this is the most efficient way, but:
>>> ''.join(c for c in "abc123def456" if c.isdigit())
'123456'
The ''.join part means to combine all the resulting characters together without any characters in between. Then the rest of it is a list comprehension, where (as you can probably guess) ...
Passing data between a fragment and its container activity
...
Since you are accessing a function within YOUR Activity (and not the parent Android activity) you will need to cast your getActivity() call: ((MyActivity) getActivity()).getResult();
– Nick
Feb 21 '12 at 17...
Android - implementing startForeground for a service?
...recent versions of Android. This is how i solved it:
Activity:
override fun onCreate(savedInstanceState: Bundle?) {
val intent = Intent(this, BackgroundService::class.java)
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
startForegroundService(intent)
} else {
...
Test whether string is a valid integer
...of "+" (e.g. +30) which obviously is an integer.
Results:
$ int_check.sh 123
123 is an integer !!
$ int_check.sh 123+
ERROR: first parameter must be an integer.
$ int_check.sh -123
-123 is an integer !!
$ int_check.sh +30
+30 is an integer !!
$ int_check.sh -123c
ERROR: first parameter must be...