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I have two raster with x points on it like this:
I have this data from each raster in a array like this:
[
[200,330],
[500,800]
]
How can i compare this data to figure out how many percent as equal this both grids to each other?
My idea is to generate a hash and compare this both hashes, but i don't have an idea how can i do this.
This idea comes from audio fingerprinting.
I will do this in swift or javascript.
Thanks you for each thought!
What you are looking for is to compute the similarity between two vectors.
In your case the vector looks like: [[x1,y1], [x2,y2], ...,[xn, yn]]
I would recommend Cosine Similarity.
The implementation is pretty straight forward, regardless the programming language.
(There are existing implementation of Cosine Similarity out there, for example In JavaScript)
Related
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I need to arrange an array from highest to lowest in a function
i have used array.sort but was informed that that was not allowed for my exerccise
function minmax(array){
var ar = array.sort().join();//I cant use array.join methood
return ar
}
Please help out
One solution could be to implement any of the popular sorting algorithms, but make the comparison used prioritize larger numbers. One example is this link, the code of which only needs a > flipped to a <.
Note that if this is a homework or school excercise, copying from anywhere is plagiarism and is generally discouraged.
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I've always wondered how on earth does Javascript picks a random number and how can it possibly be random? Don’t computers just take in some input, swirl it around with some math, and then return it?
I'm not asking how to generate a random number with Math.random(), my question is: What happens when you want to generate a ‘random’ number? How does that even work and what’s happening behind the scenes? I understand it's a big topic to discuss but any links will be appreciated!
Some random number generator functions use some kind of system noise or entropy (eg: current timestamp) and apply some mathematical function to it to generate random numbers. They are "true" random numbers.
Some functions work by using a seed value and an algorithm to generate numbers that appear to be random, but that is in fact predictable. They are called "Pseudorandom" numbers.
You can read more here: https://www.howtogeek.com/183051/htg-explains-how-computers-generate-random-numbers/
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my question why we initialize array in different ways.
as i initialize array in php like array();
and in javascript in different way.
please anyone explain difference between array() and Array().
Thanks.
The shortest answer is that they are completely different languages and, just as different spoken languages have different grammar and vocabularies from each other, so do programming languages.
Beyond that, every programming language has to have some sort of runtime or compiler that understands the syntax, data structures, processing model, etc. And, each of those environments are free to implement those details as they see fit. This means that how an Array is internalized can be quite different between languages. But, to the programmer, we don't really need (or care) to know those implementation details.
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I'm making an app and need to store several collections which refer to each other and I want to use JSON.
A little background info. the app will allow the user to create a plan/map of a garden, dividing it into different areas for each category. Then plants can be chosen for each category to grow in that area of the garden. Based on the idea that you can rotate the categories each year to a different part of the garden.
I have the following collections:
categories (in this case type of vegetables/ fruit)
plants (refer to a category)
spaces which contain an array plant ID's
So what would be best practice? store these in 3 separate files or in one?
Would there be a significant speed difference (on mobile devices perhaps?)
I apologize if this was asked before, I tried searching, but couldn't find what I was looking for.
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I made a website that does absolutely nothing, and I've proven to myself that people like to stay there - I've already logged 11+ hours worth of cumulative time on the page.
My question is whether it would be possible (or practical) to use the website as a distributed computing site.
My first impulse was to find out if there were any JavaScript distributed computing projects already active, so that I could put a piece of code on the page and be done. Unfortunately, all I could find was a big list of websites that thought it might be a cool idea.
I'm thinking that I might want to start with something like integer factorization - in this case, RSA numbers. It would be easy for the server to check if an answer was correct (simply test for modulus equals zero), and also easy to implement.
Is my idea feasible? Is there already a project out there that I can use?
Take a look at http://www.igvita.com/2009/03/03/collaborative-map-reduce-in-the-browser/ and http://www.igvita.com/2009/03/07/collaborative-swarm-computing-notes/