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Regular expression for floating point numbers
...g a floating point number is
[+-]?([0-9]*[.])?[0-9]+
This will match:
123
123.456
.456
See a working example
If you also want to match 123. (a period with no decimal part), then you'll need a slightly longer expression:
[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)
See pkeller's answer for a fuller...
How to determine a Python variable's type?
...
Use the type() builtin function:
>>> i = 123
>>> type(i)
<type 'int'>
>>> type(i) is int
True
>>> i = 123.456
>>> type(i)
<type 'float'>
>>> type(i) is float
True
To check if a variable is of a given type, u...
Reshaping data.frame from wide to long format
... 1952 10,058
7: AFG Afghanistan 1953 23,557
8: ALB Albania 1953 11,123
9: AFG Afghanistan 1954 24,555
10: ALB Albania 1954 12,246
Some alternative notations:
melt(setDT(wide), id.vars = 1:2, variable.name = "year")
melt(setDT(wide), measure.vars = 3:7, variable.name = "year")
melt...
Unable to set data attribute using jQuery Data() API
...('#changeData').click(function() {
$('#foo').data('helptext', 'Testing 123');
// $('#foo').attr('data-helptext', 'Testing 123');
console.log($('#foo').data('data-helptext'));
return false;
});
See demo
Using the Chrome DevTools Console to inspect the DOM, the $('#foo').data('helptext...
How do I create a parameterized SQL query? Why Should I?
...
'Connection string for mysql
Public SQLSource As String = "Server=123.456.789.123;userid=someuser;password=somesecurepassword;database=somedefaultdatabase;"
'database connection classes
Private DBcon As New MySqlConnection
Private SQLcmd As MySqlCommand
Public DBDA As New ...
How to unset a JavaScript variable?
...hen the target isn't an object property. e.g.,
(function() {
var foo = 123;
delete foo; // wont do anything, foo is still 123
var bar = { foo: 123 };
delete bar.foo; // foo is gone
}());
But since global variables are actually members of the window object, it works.
When prototype c...
Convert string to integer type in Go?
... fmt.Printf("i=%d, type: %T\n", i, i)
}
Output (if called with argument "123"):
i=123, type: int
i=123, type: int64
i=123, type: int
Parsing Custom strings
There is also a handy fmt.Sscanf() which gives even greater flexibility as with the format string you can specify the number format (like ...
Can I mix MySQL APIs in PHP?
...swered Jul 9 '15 at 13:59
Rizier123Rizier123
55k1616 gold badges7777 silver badges119119 bronze badges
...
Is it possible to forward-declare a function in Python?
...
Borodin
123k99 gold badges6464 silver badges134134 bronze badges
answered Oct 19 '09 at 19:36
RichNRichN
...
How can I pass a list as a command-line argument with argparse?
...'<Required> Set flag', required=True)
# Use like:
# python arg.py -l 1234 2345 3456 4567
nargs='+' takes 1 or more arguments, nargs='*' takes zero or more.
append
parser.add_argument('-l','--list', action='append', help='<Required> Set flag', required=True)
# Use like:
# python arg.p...