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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...hould work:
SELECT CASE WHEN myfield~E'^\\d+$' THEN myfield::integer ELSE 0 END FROM mytable;
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Better way to shuffle two numpy arrays in unison
...ple: Let's assume the arrays a and b look like this:
a = numpy.array([[[ 0., 1., 2.],
[ 3., 4., 5.]],
[[ 6., 7., 8.],
[ 9., 10., 11.]],
[[ 12., 13., 14.],
[ 15., 16., 17.]]])
b = numpy.a...
0.1 float is greater than 0.1 double. I expected it to be false [duplicate]
...loat. float has 24 binary bits of precision, and double has 53. In binary, 0.1 is:
0.1₁₀ = 0.0001100110011001100110011001100110011001100110011…₂
^ ^ ^ ^
1 10 20 24
So if we round up at the 24th digit, we'll get
0.1₁₀ ~ 0.00011...
how to use sed, awk, or gawk to print only what is matched?
... tried * instead and I added p tag for printing match:
sed -n 's/^.*abc\([0-9]*\)xyz.*$/\1/p' example.txt
For matching at least one numeric character without +, I would use:
sed -n 's/^.*abc\([0-9][0-9]*\)xyz.*$/\1/p' example.txt
...
Why do indexes in XPath start with 1 and not 0?
...with VBScript with its odd features such as 1-based index instead of 0-based indexes like almost every other language has, the reasoning being that it was a language for users (e.g. Excel VBA) instead of a language for developers.
...
How to get a DOM Element from a JQuery Selector
...
You can access the raw DOM element with:
$("table").get(0);
or more simply:
$("table")[0];
There isn't actually a lot you need this for however (in my experience). Take your checkbox example:
$(":checkbox").click(function() {
if ($(this).is(":checked")) {
// do stuff
...
What's the best way to check if a String represents an integer in Java?
...ncerned with potential overflow problems this function will perform about 20-30 times faster than using Integer.parseInt().
public static boolean isInteger(String str) {
if (str == null) {
return false;
}
int length = str.length();
if (length == 0) {
return false;
...
Removing leading zeroes from a field in a SQL statement
...ve the leading zeroes from a particular field, which is a simple VARCHAR(10) field. So, for example, if the field contains '00001A', the SELECT statement needs to return the data as '1A'.
...
Counting the number of True Booleans in a Python List
...rams
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Comparing strings with == which are declared final in Java
...le (non-final version) is compiled to the following byte code:
Code:
0: ldc #2; //String str
2: astore_1
3: ldc #3; //String ing
5: astore_2
6: new #4; //class java/lang/StringBuilder
9: dup
10: invokespecial #5; //Method java/lang/StringBuilder."&l...