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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.)
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impr...
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.
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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...
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,...
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.
...
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 ...
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.
...
How to resize a custom view programmatically?
...om view, extended from RelativeLayout, and I want to resize it programmatically, How can I do?
14 Answers
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