Questions

Delete a column from a Pandas DataFrame

To delete a column in a DataFrame, I can successfully use: ``` del df['column_name'] ``` But why can't I use the following? ``` del df.column_name ``` Since it is possible to access the Series via `...

6 Feb at 03:5

Check if a value is an object in JavaScript

How do you check if a value is an object in JavaScript?

25 Sep at 22:52

How to reload .bashrc settings without logging out and back in again?

If I make changes to `.bashrc`, how do I reload it without logging out and back in?

3 Jan at 22:4

Download a specific tag with Git

I'm trying to figure out how I can download a particular tag of a Git repository - it's one version behind the current version. I saw there was a tag for the previous version on the git web page, wit...

29 Jan at 19:5

How do I iterate over a range of numbers defined by variables in Bash?

How do I iterate over a range of numbers in Bash when the range is given by a variable? I know I can do this (called "sequence expression" in the Bash [documentation](http://www.gnu.org/software/bash...

1 Sep at 19:4

Delete an element from a dictionary

How do I delete an item from a dictionary in Python? Without modifying the original dictionary, how do I obtain another dict with the item removed? --- [How can I remove a key from a Python diction...

12 Feb at 10:39

How to lazy load images in ListView in Android

I am using a `ListView` to display some images and captions associated with those images. I am getting the images from the Internet. Is there a way to lazy load images so while the text displays, the ...

How do I recursively grep all directories and subdirectories?

How do I recursively `grep` all directories and subdirectories? ``` find . | xargs grep "texthere" * ```

18 Nov at 20:24

Find object by id in an array of JavaScript objects

I've got an array: ``` myArray = [{'id':'73','foo':'bar'},{'id':'45','foo':'bar'}, etc.] ``` I'm unable to change the structure of the array. I'm being passed an id of `45`, and I want to get `'bar...

Does Java support default parameter values?

I came across some Java code that had the following structure: ``` public MyParameterizedFunction(String param1, int param2) { this(param1, param2, false); } public MyParameterizedFunction(Strin...

How can I update NodeJS and NPM to their latest versions?

### I just installed Node.js & NPM (Node Package Manager) I installed NPM for access to additional Modules. After I installed Node.js & NPM I noticed that neither were the latest versions availabl...

How to replace master branch in Git, entirely, from another branch?

I have two branches in my Git repository: 1. master 2. seotweaks (created originally from master) I created `seotweaks` with the intention of quickly merging it back into `master`. However, that ...

19 Aug at 18:8

Preview an image before it is uploaded

I want to be able to preview a file (image) before it is uploaded. The preview action should be executed all in the browser without using Ajax to upload the image. How can I do this?

6 Sep at 10:49

How do I check if a variable is an array in JavaScript?

How do I check if a variable is an array in JavaScript? ``` if (variable.constructor == Array) ```

10 Apr at 12:59

What is the optimal algorithm for the game 2048?

I have recently stumbled upon the game [2048](http://gabrielecirulli.github.io/2048/). You merge similar tiles by moving them in any of the four directions to make "bigger" tiles. After each move, a n...

How to get a Docker container's IP address from the host

Is there a command I can run to get the container's IP address right from the host after a new container is created? Basically, once Docker creates the container, I want to roll my own code deploymen...

8 Apr at 13:32

How to stop tracking and ignore changes to a file in Git?

I have cloned a project that includes some `.csproj` files. I don't need/like my local `csproj` files being tracked by Git (or being brought up when creating a patch), but clearly they are needed in t...

19 Nov at 13:42

Why is it string.join(list) instead of list.join(string)?

This has always confused me. It seems like this would be nicer: ``` ["Hello", "world"].join("-") ``` Than this: ``` "-".join(["Hello", "world"]) ``` Is there a specific reason it is like this?

1 Apr at 02:51

How do I break out of nested loops in Java?

I've got a nested loop construct like this: ``` for (Type type : types) { for (Type t : types2) { if (some condition) { // Do something and break... break; // Br...

6 Dec at 06:35

Writing to files in Node.js

I've been trying to find a way to write to a file when using Node.js, but with no success. How can I do that?

8 Mar at 09:36

How to check if the string is empty?

Does Python have something like an empty string variable where you can do: ``` if myString == string.empty: ``` Regardless, what's the most elegant way to check for empty string values? I find hard...

How do I format XML in Notepad++?

I have [Notepad++](http://en.wikipedia.org/wiki/Notepad%2B%2B) and I got some XML code which is very long. When I pasted it in Notepad++ there was a long line of code (difficult to read and work with)...

6 Apr at 01:35

Config Error: This configuration section cannot be used at this path

I've encountered an error deploying a site to a server. When trying to load the home page, or access authentication on the new site in IIS, I get the error: > Config Error: This configuration sectio...

21 Feb at 18:38

Detecting an "invalid date" Date instance in JavaScript

I'd like to tell the difference between valid and invalid date objects in JS, but couldn't figure out how: ``` var d = new Date("foo"); console.log(d.toString()); // shows 'Invalid Date' console.log(...

5 Jul at 19:34

Difference between static class and singleton pattern?

What real (i.e. practical) difference exists between a static class and a singleton pattern? Both can be invoked without instantiation, both provide only one "Instance" and neither of them is thread-...

15 Nov at 15:2