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How do you check in python whether a string contains only numbers?
...isdigit method on your str object:
if len(isbn) == 10 and isbn.isdigit():
From the isdigit documentation:
str.isdigit()
Return True if all characters in the string are digits and there is at least one character, False otherwise. Digits include decimal characters and digits that need special handli...
What is the correct syntax for 'else if'?
I'm a new Python programmer who is making the leap from 2.6.4 to 3.1.1. Everything has gone fine until I tried to use the 'else if' statement. The interpreter gives me a syntax error after the 'if' in 'else if' for a reason I can't seem to figure out.
...
How do I get an element to scroll into view, using jQuery?
...):
var offset = $(this).offset(); // Contains .top and .left
Subtract 20 from top and left:
offset.left -= 20;
offset.top -= 20;
Now animate the scroll-top and scroll-left CSS properties of <body> and <html>:
$('html, body').animate({
scrollTop: offset.top,
scrollLeft: offse...
append new row to old csv file python
...
I prefer this solution using the csv module from the standard library and the with statement to avoid leaving the file open.
The key point is using 'a' for appending when you open the file.
import csv
fields=['first','second','third']
with open(r'name', 'a') as f:...
Why is Maven downloading the maven-metadata.xml every time?
...wnloaded once, unless refresh is forced with -U or the artifact is removed from local repo and thus needs to be redownloaded.
– user944849
Jan 11 '19 at 17:28
add a comment
...
Better explanation of when to use Imports/Depends
... use "Depends").
A "Depends" directive attempts to ensure that a function from another package is available by attaching the other package to the main search path (i.e. the list of environments returned by search()). This strategy can, however, be thwarted if another package, loaded later, places a...
Where can I find Android source code online? [closed]
... One can indeed get individual packages by pulling their git repositories from a currently active URL. However, this is mostly useful for study - even things that seem like they should be SDK-based ordinary applications typically have dependencies elsewhere in AOSP and so will not build via the SD...
Node.js - getting current filename
...
@Cullub, extract from the nodejs documentation: These CommonJS variables are not available in ES modules. Equivalents of __filename and __dirname can be created inside of each file via import.meta.url.
– herve
...
Structs in Javascript
...tween object literals and constructed objects are the properties inherited from the prototype.
var o = {
'a': 3, 'b': 4,
'doStuff': function() {
alert(this.a + this.b);
}
};
o.doStuff(); // displays: 7
You could make a struct factory.
function makeStruct(names) {
var names = names....
How to compare versions in Ruby?
...default; you need a require 'rubygems' to get access to the Gem namespace. From 1.9 on, however, it's automatically included.
– Mark Reed
Feb 12 '14 at 14:35
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