Re: complex numbers in clojure

I leave it to others to assess the tradeoffs, but: Anything that's done to better support scientific computing has potential to pay off in the long run with greater popularity for Clojure. Most, or many scientists work in universities. Professors have students--lots of students, over time.

Re: complex numbers in clojure

On 2 Nov 2015, at 13:11, Grahack wrote: > I'm resurrecting this thread in case there is something new that happened > concerning complex numbers that was not logged here. > So was there some progress made? > > I also wanted to add that mixing rationals and complex

Re: complex numbers in clojure

I'll just add that core matrix complex doesn't prevent you from using rationals, as most of the math happens on real/imaginary matrix pairs. However, any time you try to return a scalar value (not a matrix), it wraps the result using the alanforr library, so you'd be potentially restricted there,

Re: complex numbers in clojure

I'm resurrecting this thread in case there is something new that happened concerning complex numbers that was not logged here. So was there some progress made? I also wanted to add that mixing rationals and complex wuold be super cool, like: (* 1/2 i) => i/2) -- You received this message

Re: complex numbers in clojure

On 2 Nov 2015, at 15:57, Christopher Small wrote: > I'll just add that core matrix complex doesn't prevent you from using > rationals, as most of the math happens on real/imaginary matrix pairs. > However, any time you try to return a scalar value (not a matrix), it wraps

Re: complex numbers in clojure

On 28 April 2015 at 05:22, Mikera mike.r.anderson...@gmail.com wrote: Complex numbers are tricky because: - They need to be fast in order to be useful for numerical computing. The obvious implementations that you might create with boxed values, vectors/maps, multimethods and protocols are

Re: complex numbers in clojure

For me, having complex numbers not work seamlessly with other numbers and core arithmetic ops is not viable. Doing arithmetic ops with any kind of number is a real (pardon the pun) use case. If complex numbers are not likely to be supported fully, then maybe it makes sense to have complex

Re: complex numbers in clojure

Hi Before we try to guess what Rich will or won't think or want, are you interested in a proof of concept? So we could evaluate performance and complexity issues before the subject is definitively buried. What do you think about it? Plínio On Wed, Apr 29, 2015 at 12:56 AM, Mikera

Re: complex numbers in clojure

Ideally math APIs would be cross-platform #ClojureScript -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first

Re: complex numbers in clojure

Let me first say I would definitely like to see complex arithmetic support in Clojure. Major hole for scientific computing in my opinion. And with the momentum that Clojure has in ML / data science, I think it's one that needs patching. As to you specific point Nik: For me, having complex

Re: complex numbers in clojure

Yes, it would be nice to have this available for cljs as well. With the new reader literals though, this doesn't preclude having a native java implementation that gets loaded in the :clj case, and some other implementation that gets loaded in the :cljs case. On Wednesday, April 29, 2015 at

Re: complex numbers in clojure

It does seem as though there is no way to meet all the criteria, unless the support for it comes from Java/Oracle. That said, I feel like having a complex type with reasonable performance is better than having nothing at all. What I would like is a complex type that plays well with Clojure's

Re: complex numbers in clojure

My two cents: I started to develop some support to complex numbers in Clojure, but I don't know if the Core Team/Rich Hickey has any intererest in this subject. Even it's an unfinished work, I didn't notice any lost of performance so far. Regards Plínio Balduino On Tue, Apr 28, 2015 at 9:35

Re: complex numbers in clojure

To put is simply, it would be nice to have a complex type in Clojure, not as a separate namespace, but something that is part of the language. It should interoperate with other Clojure types (like adding a double to a complex), as well as clojure.core.arithmetic. That's what I meant about

Re: complex numbers in clojure

Your messages are a bit confusing. Playing nice with collection functions would depend on the collection, not on its contents. Maybe you could elaborate a bit more on what you're trying to accomplish? If you do not care about performance, you need to decide whether you want your type to work

Re: complex numbers in clojure

Most of Clojure's collections already can hold arbitrary type values inside of them, with no additional work required, whether those types are built into Clojure or not. That is because most collections treat all contained items as Java Object references. The only exceptions I can think of are

Re: complex numbers in clojure

You can do virtually all of that already with the Apache commons Complex class. Any Java object can be just fine used with map / reduce / filter / seqs etc. If you want to avoid Java interop and make things more Clojure-like then a lightweight wrapper library is all that is needed (my

Re: complex numbers in clojure

Not that tricky, really. But there's a lot of repetitive work. I changed the Clojure readers to understand the a+bi format, created a ComplexNumber class and changed the class on charge of arithmetic to work with complex numbers. So it's possible to make any operation mixing Numbers, Ratios and

Re: complex numbers in clojure

I think it's unlikely that Clojure would add a complex number type. However, it might be possible to open up the system enough that new types could be created and integrated by others. I think this discussion and implementation from clojure-dev (about unsigned numbers) is pertinent:

Re: complex numbers in clojure

Complex numbers are tricky because: - They need to be fast in order to be useful for numerical computing. The obvious implementations that you might create with boxed values, vectors/maps, multimethods and protocols are likely to be unacceptable for many use cases - You still want to be able to

Re: complex numbers in clojure

I have been thinking along the lines of mikera and Maik - and it seems like there is no further progress here? I would like to take a crack at creating a complex number type, but implemented as a library to Clojure. I am not sure where to start, and if anyone here has suggestions, I'd be happy

Re: complex numbers in clojure

Unless the Java Math library handles complex types already, I don't know of any way to extend it in a way that would let you get the answer you want from (Math/abs my-complex-number) in Clojure. If you want code that gives the correct answers, a library using vectors or maps for complex numbers

Re: complex numbers in clojure

As far as I understand, your example with Math/abs would need to be part of Java. You cannot extend the arithmetic operators in Java, and you will not be able to extend static Java methods like Math/abs. What you may be able to do is make your custom type play nice with Clojure operators, like

Re: complex numbers in clojure

This is what I suspected. Of course, this is not just for abs, but really for any mathematical operation. Sqrt, Trig operations etc. I will study the Ratio type more closely, but note that something like (Math/abs (/ 22 7)) does not work. On Monday, April 27, 2015 at 12:45:32 PM UTC-4, Gary

Re: complex numbers in clojure

As far as I know, Java Math does not have a complex number type. Some implementations of a complex number exist (such as Apache Commons Math), but they create a Complex class that implements Serializeable and a Commons specific interface. Modifying clojure.core itself is a bit daunting, and

Re: complex numbers in clojure

People frequently make their own modified versions of Clojure without having their changes made part of the core Clojure distribution. That is why I said depending upon your goals. If your goal is to try it out and learn from it, and you don't care whether it becomes part of the standard Clojure

Re: complex numbers in clojure

Just cheerleading: I, for one, would love for Clojure to have complex number support, however it can be arranged (built-in or through a library). I sometimes do quantum computing work and this issue has prevented progress on a couple of projects. I haven't tried to solve the problem myself,

Re: complex numbers in clojure

There is really no perfect numerical type: - primitive doubles are best if you care about performance and reasonably good precision (but no complex numbers!) - boxed Doubles are needed in some circumtances, e g. storage in collections, passing to dynamic code - something like

Re: complex numbers in clojure

I agree that Clojure could really use an imaginary number type. The best place to start with this might be `clojure.math.numeric-tower` because it already provides a `MathFunctions` protocol that defines a square root operation. Cheers Jan On 15 Aug 2014, at 19:54, Maik Schünemann

Re: complex numbers in clojure

I agree with mikera on this, the standard numeric abstraction have to be able to fulfill all performance needs. This definitly excludes multimethods (algo.generic) and protocols/interface-calls (numeric-tower). (Imagine multiplying two 5000x5000 matrices and having to go through a protocol for

complex numbers in clojure

Hi, is there a recommended way to do complex arithmetic in clojure ? I am interested to see clojure going forward for scientific computing purposes. There is already considerable effort going on with core.matrix, incanter, expresso etc. But something thad is oddly lacking is support for

Re: complex numbers in clojure

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 The best way to build a complex arithmetic package is probably to work atop `clojure.algo.generic`. I've done a pair of libraries (https://github.com/arrdem/imprecise, https://github.com/arrdem/meajure) based around extending algo.generic with custom

Re: complex numbers in clojure

Hi, On Fri, Aug 15, 2014 at 7:00 PM, Reid McKenzie rmckenzi...@gmail.com wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 The best way to build a complex arithmetic package is probably to work atop `clojure.algo.generic`. I've done a pair of libraries (