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Count number of objects in list [closed]
... me : beware, the following is a list of a single object :
> mylist <- list (1:10)
> length (mylist)
[1] 1
In such a case you are not looking for the length of the list, but of its first element :
> length (mylist[[1]])
[1] 10
This is a "true" list :
> mylist <- list(1:1...
Does JavaScript have a method like “range()” to generate a range within the supplied bounds?
...d functions
function range(size:number, startAt:number = 0):ReadonlyArray<number> {
return [...Array(size).keys()].map(i => i + startAt);
}
function characterRange(startChar:string, endChar:string):ReadonlyArray<string> {
return String.fromCharCode(...range(endChar.charCodeA...
iFrame src change event detection?
...
You may want to use the onLoad event, as in the following example:
<iframe src="http://www.google.com/" onLoad="alert('Test');"></iframe>
The alert will pop-up whenever the location within the iframe changes. It works in all modern browsers, but may not work in some very older b...
background function in Python
I've got a Python script that sometimes displays images to the user. The images can, at times, be quite large, and they are reused often. Displaying them is not critical, but displaying the message associated with them is. I've got a function that downloads the image needed and saves it locally. Rig...
How to create a listbox in HTML without allowing multiple selection?
...g to create a simple listbox, but one of the requirements is to DISALLOW multiple selection. Most of the code for listboxes goes like this -
...
Android: why is there no maxHeight for a View?
...
This might not work in all situations, but it certainly gives me the results needed for my layout. And it also addresses the comment by madhu.
If some layout present below the scrollview then this trick wont work – madhu Mar 5 at 4:36
...
How do I select a random value from an enumeration?
...om array item.
static Random _R = new Random ();
static T RandomEnumValue<T> ()
{
var v = Enum.GetValues (typeof (T));
return (T) v.GetValue (_R.Next(v.Length));
}
Test:
for (int i = 0; i < 10; i++) {
var value = RandomEnumValue<System.DayOfWeek> ();
Console.WriteL...
Java 8 Distinct by property
In Java 8 how can I filter a collection using the Stream API by checking the distinctness of a property of each object?
2...
Create a git patch from the uncommitted changes in the current working directory
... are untracked": "git diff" and "git diff --cached" only work if "git add <file>" has been called first. (I am new to git and wondered why I got an empty patch everytime)
– Anonymous
Apr 25 '17 at 8:41
...
How can I convert byte size into a human-readable format in Java?
...public static String humanReadableByteCountSI(long bytes) {
if (-1000 < bytes && bytes < 1000) {
return bytes + " B";
}
CharacterIterator ci = new StringCharacterIterator("kMGTPE");
while (bytes <= -999_950 || bytes >= 999_950) {
bytes /= 1000;
...