Recent content by aphirst

As part of my work, I'm making use of the familiar properties of function minima/maxima in a way which I can't seem to find in the literature. I was hoping that by describing it here, someone else might recognise it and be able to point me to a citation. I think it's highly unlikely that I'm the...

Is it possible to introduce a distinction between "no replies" and "unanswered"? What I mean is, I made a thread the other day, and for reasons of clarity made a 2nd post, which now means my thread no longer shows up in "unanswered threads" despite in no way actually being answered. It seems...

It's probably better to talk explicitly in terms of ##\mathbf{s}(u,v,q)## and ##\mathbf{f}(u,v,q)##, and restate that the path "##\mathrm{d}\mathbf{s}##" is actually a path through ##u,v## (where the path itself depends on ##q## due to ##q##'s impact on ##\mathbf{s}(u,v,q)## and on the unstated...

As part of the work I'm doing, I'm evaluating a contour integral: $$\Omega \equiv \oint_{\Omega} \mathbf{f}(\mathbf{s}) \cdot \mathrm{d}\mathbf{s}$$ along the border of a region on a surface ##\mathbf{s}(u,v)##, where ##u,v## are local curvilinear coordinates, and where the surface itself is...

Of course they are how they are for a lot of good reasons (some of which I explicitly enumerate). My point is simply that these resources are not especially useful for actually Modern Fortran.

If one wishes to actually use Fortran in 2018, and is not strictly forced to use an older version of the language standard, I would certainly strongly recommend familiarising yourself with truly Modern Fortran, i.e. F2003 and F2008, both of which are now "almost entirely" implemented in gfortran...

If the book has been listed on ResearchGate, you will usually get this information as part of whatever aggregation process they do behind-the-scenes (assuming also that the citers/citees are in the same databases).

Yet further analysis raises the following points about the possible extreme cases of ##\cos(\theta)##: 1. ##\Delta \mathbf{X}_{GD} \perp \Delta \mathbf{X}_{NR} \Leftrightarrow \cos(\theta) = 0~,## and this can only occur either for ##\mathbf{F}=0##, or when either...

In light of @FactChecker 's post talking about the properties of objective functions, I feel the need to re-emphasise that my ultimate goal is not merely to minimise a merit function, but indeed actually to solve ##\mathbf{F}(\mathbf{X})=\mathbf{0}## a system of nonlinear equations. This is...

I would like to come back to this topic, as this is becoming a subsection of my thesis work, so it's of utmost importance that I can address the topic concisely and correctly. Let us continue to suppose that we have a function ##\vec{F}(\vec{X})## where both are of length (dimension) ##N##, and...

I think your comment on N-R being a case of quadratic programming has already set me in the right direction. From what I'm seeing so far, it's never so much that you "need N-R to solve the higher dimensional problem" but rather that "if you know you're in a region of essentially quadratic...

I am of course using existing tools for solving my actual problems, my question was more to ensure that I have a thorough understanding of what I'm doing and why I'm using the tools I am, and why they do what they do, along with the ability to provide comprehensive arguments and citations...

Hi @Taylor_1989 There are a few options which should let you preserve the syntax highlighting without having to resort to screenshots. For example, this stackexchange entry demonstrates how to use LaTeX for this. Mentioned in the discussion are another program ostensibly useful just for...

@moebot Are you able to provide some comments to your code, such as What the equation is, whose root(s) you're trying to find What you are intending each section of code to do Why you're writing in F77 (fixed) style with GOTOs instead of loops ?

I would just like to chip into contest the frequently asserted claim that "Fortran is a language where calls are intrinsically by-reference", by "referring" to a blog post by Steve Lionel a.k.a. Doctor Fortran (formerly?) of Intel...