Just want to say I sent this before all the other comments - including the talk by Danie Spiewak and the Sedgewick and Wayne book on Algorithms - so I'll definitely have a look at those too.
Thanks again for all the advice! On Mar 20, 6:45 pm, Nic Long <nicolasl...@gmail.com> wrote: > Hey, just want to say thanks for all the advice! And Andy especially > for the kind offer - I may well PM some specific questions once I > start reading. > > The Cormen et al. book looks great - tough but exactly what I need - > so I'm going to pick up a copy. And I'll also read the PhD thesis on > Functional Data Structures suggested by Nuno. > > On Mar 19, 8:02 pm, Nuno Marques <nuno.filipe.marq...@gmail.com> > wrote: > > > > > > > > > This book: > > > Purely Functional Data > > Structureshttp://www.cs.cmu.edu/~rwh/theses/okasaki.pdf > > > is a good read. > > > Though, It only contains a small reference (half a page) about persistent > > data structures. > > > On Mar 19, 2012, at 7:28 PM, Andy Fingerhut wrote: > > > > I've got my copy of Cormen, Leiserson, and Rivest's book with me now, > > > which is the 3rd edition, and looking in the index under "persistent" it > > > does have one exercise in chapter 13 on that topic, and a mention later > > > in the book that is a paragraph or two long with a reference to a > > > research paper. > > > > So while that book isn't a good reference for persistent data structures > > > in particular, it is a good reference for the more widely known (and some > > > not-so-widely known) mutable data structures. If you learn at least a > > > few of those, then you are very well prepared to understand Clojure's > > > persistent data structures, too, and there are blog posts on the topic > > > that can get you a lot of the way there (once you understand the basics), > > > e.g.: > > > >http://blog.higher-order.net/2009/09/08/understanding-clojures-persis... > > > > The book does assume a knowledge of how basic arrays work, but those are > > > quite simple and hopefully my message below is nearly as much as there is > > > to know about them. To get an understanding of data structures like hash > > > tables and some different kinds of trees, you can probably get there just > > > reading a few of the introductory sections at the beginning, and then > > > jump to those specific sections. Save all the stuff on algorithms for > > > when and if you are interested. > > > > Andy > > > > On Mar 18, 2012, at 8:57 PM, Andy Fingerhut wrote: > > > >> Feel free to ask follow-up questions on the basics privately, since many > > >> Clojure programmers are probably already familiar with them, whereas > > >> follow-up questions on persistent data structures are very on-topic, > > >> since I would guess many people who have studied computer science and/or > > >> programming for a while may not be familiar with them. > > > >> The classic model of an array is based upon the implementation of > > >> physical RAM in a computer: a physical RAM, at a high level and leaving > > >> out details of variations, is a device where you either give it a > > >> command READ and an address, and it returns an 8-bit byte stored at that > > >> location, or you give it a WRITE command, an address, and an 8-bit > > >> value, and it stores the 8-bit value at the location given by the > > >> address. > > > >> A classic array is a one-dimensional structure indexed by an integer i, > > >> usually from 0 up to some maximum value N, and every item in the array > > >> stores an item of the same size and type, e.g. all 32-bit integers, or > > >> all pointers to some object elsewhere in the memory. If every item fits > > >> in exactly B bytes, and the first item of the array begins at address A > > >> in the memory, then item i will be at address A+B*i in the memory. In > > >> terms of performance, computers are designed to be able to access any > > >> address in their memory in the same amount of time, no matter what > > >> address it is stored at, so with a couple of instructions to calculate > > >> A+B*i, the computer can read or write any element of an array within a > > >> constant amount of time (constant meaning it doesn't get larger or > > >> smaller depending upon the size of the array -- it is always the same no > > >> matter the array's size). With other non-array data structures like > > >> trees, accessing an element takes longer as the data structure grows to > > >> contain more items. > > > >> I don't recall if it covers persistent data structures like the ones > > >> most commonly used in Clojure, but Cormen, Leiserson, and Rivest's > > >> "Introduction to Algorithms" is used in many colleges as a text in > > >> courses on algorithms and data structures. There are probably other > > >> books that would be better as a "primer", and it does assume you are > > >> comfortable with at least algebra and a bit more math, but if you got > > >> through a chapter of it and understood even half of it, you'd have > > >> learned something worth knowing about the subject. > > > >>http://www.amazon.com/Introduction-Algorithms-Includes-CD-Rom-Thomas/... > > > >> There is a newer edition than the one I linked to, but an older used > > >> copy for $25.00 might be closer to what you want if you aren't sure yet. > > > >> Andy > > > >> On Mar 15, 2012, at 12:15 PM, Nic Long wrote: > > > >>> Hi all, > > > >>> I am starting to learn Clojure after buying the book 7 Languages in 7 > > >>> Weeks (really interesting read) and working through the examples > > >>> there. But my background is PHP (and no Computer Science degree) so my > > >>> understanding of data structures and in general, my understanding of > > >>> low-level CS ideas, is pretty limited to say the least - PHP only has > > >>> arrays (which I read are only 'ordered hash tables' in fact) and > > >>> objects so I've never had to think hard about which data structures to > > >>> use, nor how they actually work. > > > >>> So I guess I'm asking whether anyone can recommend some good primers > > >>> on data structures, both as they relate to Clojure, but also how they > > >>> work in the fundamentals - e.g. what exactly is the classic model of > > >>> an 'array' and how does it work, etc. I have read the various > > >>> performance commitments for the data-types in Clojure on the .org site > > >>> but even things like Big O notation are still pretty new to me. > > > >>> I'm sure this stuff is pretty basic for many, but I don't know it and > > >>> would like to! > > > >>> I'm not afraid of some heavy reading; I'd rather get a really deep and > > >>> solid grasp of the fundamentals, then a quick surface-level solution. > > >>> If I'm to develop as a programmer I feel like I need to get looking > > >>> under the hood as it were, even though I can get by in PHP (for the > > >>> most part anyway) without this kind of understanding. > > > >>> Thanks in advance, > > > >>> Nic > > > >>> -- > > >>> 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 post. > > >>> To unsubscribe from this group, send email to > > >>> clojure+unsubscr...@googlegroups.com > > >>> For more options, visit this group at > > >>>http://groups.google.com/group/clojure?hl=en > > > > -- > > > 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 post. > > > To unsubscribe from this group, send email to > > > clojure+unsubscr...@googlegroups.com > > > For more options, visit this group at > > >http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups "Clojure" group. 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