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isset() and empty() - what to use
...mpty checks if the variable is set and if it is it checks it for null, "", 0, etc
Isset just checks if is it set, it could be anything not null
With empty, the following things are considered empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array(...
Capturing Groups From a Grep RegEx
I've got this little script in sh (Mac OSX 10.6) to look through an array of files. Google has stopped being helpful at this point:
...
When to use “new” and when not to, in C++? [duplicate]
...s out of scope. Some examples of this are:
void foo()
{
Point p = Point(0,0);
} // p is now destroyed.
for (...)
{
Point p = Point(0,0);
} // p is destroyed after each loop
Some people will say that the use of new decides whether your object is on the heap or the stack, but that is only true...
How do you read CSS rule values with JavaScript?
...(className) {
var cssText = "";
var classes = document.styleSheets[0].rules || document.styleSheets[0].cssRules;
for (var x = 0; x < classes.length; x++) {
if (classes[x].selectorText == className) {
cssText += classes[x].cssText || classes[x].style.cssText...
How to scroll to top of page with JavaScript/jQuery?
...op once it's fully loaded. This has Cross-browser support.
window.scrollTo(0,0);
history.scrollRestoration Browser support:
Chrome: supported (since 46)
Firefox: supported (since 46)
IE/Edge: not supported (Yet..)
Opera: supported (since 33)
Safari: supported
For IE/Edge if you want to re-s...
Compare two DataFrames and output their differences side-by-side
... rows are empty*:
In [21]: ne = (df1 != df2).any(1)
In [22]: ne
Out[22]:
0 False
1 True
2 True
dtype: bool
Then we can see which entries have changed:
In [23]: ne_stacked = (df1 != df2).stack()
In [24]: changed = ne_stacked[ne_stacked]
In [25]: changed.index.names = ['id', 'col']
...
What does ** (double star/asterisk) and * (star/asterisk) do for parameters?
...s the other way around:
def foo(a, b, c):
print(a, b, c)
obj = {'b':10, 'c':'lee'}
foo(100,**obj)
# 100 10 lee
Another usage of the *l idiom is to unpack argument lists when calling a function.
def foo(bar, lee):
print(bar, lee)
l = [1,2]
foo(*l)
# 1 2
In Python 3 it is possible to...
Get number days in a specified month using JavaScript? [duplicate]
...
609
// Month here is 1-indexed (January is 1, February is 2, etc). This is
// because we're using 0...
How do I set a variable to the output of a command in Bash?
...
vstepaniuk
27022 silver badges88 bronze badges
answered Jan 10 '11 at 21:04
Andy LesterAndy Lester
...
Using NumberPicker Widget with Strings
...
NumberPicker picker = new NumberPicker(this);
picker.setMinValue(0);
picker.setMaxValue(2);
picker.setDisplayedValues( new String[] { "Belgium", "France", "United Kingdom" } );
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