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Remove empty array elements
... of strings, you can simply use array_filter(), which conveniently handles all this for you:
print_r(array_filter($linksArray));
Keep in mind that if no callback is supplied, all entries of array equal to FALSE (see converting to boolean) will be removed. So if you need to preserve elements that ...
Sorting a tab delimited file
...u probably want
sort -k4nr file.txt
to sort file.txt by column 4 numerically in reverse order. (Though the data in the question has even 5 fields so the last field would be index 5.)
share
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impr...
How to select rows from a DataFrame based on column values?
...have multiple values you want to include, put them in a
list (or more generally, any iterable) and use isin:
print(df.loc[df['B'].isin(['one','three'])])
yields
A B C D
0 foo one 0 0
1 bar one 1 2
3 bar three 3 6
6 foo one 6 12
7 foo three 7 14
Note,...
Does order of where clauses matter in SQL?
Let's say I have a table called PEOPLE having 3 columns ID, LastName, FirstName , none of these columns are indexed.
LastName is more unique, and FirstName is less unique.
...
Why can templates only be implemented in the header file?
...f;
When reading this line, the compiler will create a new class (let's call it FooInt), which is equivalent to the following:
struct FooInt
{
int bar;
void doSomething(int param) {/* do stuff using int */}
}
Consequently, the compiler needs to have access to the implementation of the m...
What is setup.py?
...ts and also from [I]Python prompts.
It does the similar job of pip, easy_install etc.,
Using setup.py
Let's start with some definitions:
Package - A folder/directory that contains __init__.py file.
Module - A valid python file with .py extension.
Distribution - How one package relates to ...
Instance variables vs. class variables in Python
...r instance. If there would be more than one instance (which won't happen), all instance should have the same configuration. I wonder which of the following options would be better or more "idiomatic" Python.
...
How to set focus on input field?
...nction ($timeout, $parse) {
return {
//scope: true, // optionally create a child scope
link: function (scope, element, attrs) {
var model = $parse(attrs.focusMe);
scope.$watch(model, function (value) {
console.log('value=', value);
...
Correct way to close nested streams and writers in Java [duplicate]
...
I usually do the following. First, define a template-method based class to deal with the try/catch mess
import java.io.Closeable;
import java.io.IOException;
import java.util.LinkedList;
import java.util.List;
public abstract cl...
count(*) vs count(column-name) - which is more correct? [duplicate]
...
COUNT(*) counts all rows
COUNT(column) counts non-NULLs only
COUNT(1) is the same as COUNT(*) because 1 is a non-null expressions
Your use of COUNT(*) or COUNT(column) should be based on the desired output only.
...