whole design intent, but this is what Inventor is good at. The way it packages bits of 'scripted' components into 'little models' that can be stored and re-assembled is central to MCAD working.
The Inventor model shown is almost 5 years old. We don't model like that any more, however it does offer a good idea of general MCAD modeling approaches.
iParts is useful in certain situations, it could've been useful in the above model, its usefulness is often in function of the quantity of variants/configurations.
So much is scripted in GH, maybe it should also be possible to script/define/constrain/assist the placement/gluing of the results?
...
Starting point: I think we are talking across purposes. AFAIK, the solving sequence of GH's scripted components is fixed. It won't do circular dependencies... without a fight. The inter-component dependencies not 'managed' like constraints solvers do for MCAD apps.
Components and assemblies are individual files in MCAD.
Placement of these within assemblies in MCAD is a product of matrix transforms and persistent constraints. There is no bi-directional link, the link is unidirectional (downflow only), because of the use of proxies.
Consequently, scripting the placement of components is irrelevant in GH, unless you decide that each component needs to be contained in its own separate file.
This also brings up the point that generating components and assemblies in MCAD is not as straightforward. In iParts and iAssemblies, each configuration needs to be generated as a "child" (the individual file needs to be created for each child) before those children can be used elsewhere.
You notice the dilemma, if you generate 100 parts, and then you realize you only need 20, you've created 80 extra parts which you have no need for, thus generating wasteful data that may cause file management issues later on.
GH remains in a transient world, and when you decide to bake geometry (if you need to at all), you can do that in one Rhino file, and save it as the state of the design at that given moment. Very convenient for design, though unacceptable for most non-digital manufacturing methods, which greatly limits Rhino's use for manufacturing unless you combine it with an MCAD app.
One of the reasons why the distributed file approach makes perfect sense in MCAD, is that in industry you deal with a finite set of objects. Generative tools are usually not a requirement. Most mechanical engineers, product engineers and machinists would never have any use for that.
The other thing that MCAD apps like Inventor have, is the 'structured' interface that offers up all that setting out information like the coordinate systems, work planes, parameters etc in a concise fashion in the 'history tree'. This will translate into user speed. GH's canvas is a bit more freeform. I suppose the info is all there and linked, so a bit of re-jigging is easy. Also, see how T-Flex can even embed sliders and other parameter input boxes into the model itself. Pretty handy/fast to understand, which also means more speed.
True. As long as you keep the browser pane/specification tree organized and easy to query.
:)
Would love to understand what you did by sketching.
I'll start by showing what was done years ago in the Inventor model, and then share with you what I did in GH, but in another post.
Let's use one of the beams as an example:
We can isolate this component for clarity.
Notice that I've highlighted the sectional sketch with dimensions, and the point of reference, which is in relation to the CL of the column which the beam bears on. The orientation and location of the beam is already set by underlying geometry.
Here's a perspective view of the same:
The extent of the beam was also driven by reference geometry, 2 planes offset from the beam's XY plane, driven by parameters from another underlying file which serves as a parameter container:
Reference axes and points are present for all other components, here are some of them:
It starts getting cluttered if you see the reference planes as well:
Is I mentioned earlier, over time we've found better ways to define and associate geometry, parameters, manage design change, improving the efficiency of parametric models. But this model is a fair representation of a basic modeling approach, and since an Inventor-GH comparison is like comparing apples and oranges anyways, this model can be used to understand the differences and similarities, for those interested.
I haven't even gotten to your latest post yet, I will eventually.…
Added by Santiago Diaz at 10:36am on February 26, 2011
peuvent se diviser une surface avec ne importe quel motif imaginable. 3. Ici, je fournir un moyen de le faire via Lunchbox ... cela fonctionne mais il est fixe et donc nous avons besoin de jouer avec des arbres de données afin de créer le motif approprié par cas. 4. L'autre composante est un joint C # qui fait beaucoup de choses autres que de diviser ne importe quelle collection de points avec de nombreux modèles (voir le modèle ANDRE que je ai fait pour vous). 5. Vous devez décomposer une polysurface en morceaux afin de travailler sur les subdivisions. 6. Je donne une autre définition ainsi que pourrait agir comme un tutoriel sur la façon de traiter des ensembles de points via des composants de GH standards et des méthodes classiques.
Avertissez si tous ceux-ci apparaissent floue pour vous: Si oui, je pourrais écrire une définition utilisant des composants de GH classiques - mais vous perdrez les variations de motifs de division.
mieux, Peter
…
olves some changes to the Rhino SDK, so it's likely that there will be problems running 0.8.0008 under Rhino5 until the next Rhino5 WIP goes out.
Changes since 0.8.0007:
● Added a Mesh|Mesh intersection component.
● Added a Mesh|Curve intersection component.
● Added a Replace List component (Sets.List dropdown)
● Added Integer Division component (Math.Operator dropdown)
● Added ToRadians component (Math.Trig dropdown)
● Added ToDegrees component (Math.Trig dropdown)
● Added Cube component (Math.Polynomials dropdown)
● Added CubeRoot component (Math.Polynomials dropdown)
● Added Round component which exposes Round, Ceiling and Floor functions (Math.Util dropdown)
● Added Negative component (Math.Operators dropdown)
● Added Absolute component (Math.Operators dropdown)
● Added 'One over X' component (Math.Polynomials dropdown)
● Updated to Quantum Whale code editor version 1.62
● Added String Sort component (Sets.Strings dropdown)
● Added Create Set component (Sets.Sets panel)
● Added Set Union component (Sets.Sets panel)
● Added Set Difference component (Sets.Sets panel)
● Added Set Symmetric Difference component (Sets.Sets dropdown)
● Added Set Intersection component (Sets.Sets panel)
● Added Set Carthesian Product component (Sets.Sets panel)
● Added SubSet test component (Sets.Sets panel)
● Added Disjoint Set test component (Sets.Sets dropdown)
● Added Set Majority component (Sets.Sets dropdown)
● Added Set Member Index component (Sets.Sets dropdown)
● Added Set Replace Member component (Sets.Sets dropdown)
● Added Set Remove Consecutive Identical Members component (Sets.Sets dropdown)
● Added Mass Multiplication component (Math.Operators dropdown)
● Simplify Tree component now by default collapses *all* coincident path elements.
● Casting error messages are now vaguely less geeky.
● Added polygon center component (Curve.Analysis dropdown).
● Font Defaults are now copied from the OS Fonts.
● Slider Initialization codes can now be used to specify decimal places.
● Profiler widget now displays long time spans in seconds, minutes and hours.
● Added an IsoVist component (Intersect.Mathematical panel)
● Added an IsoVist Ray component (Intersect.Mathematical panel)
● MRU missing file checks are now threaded to prevent UI delays when files are located on slow media.
● Expression Editor has been redesigned.
● Slider Component popup has been redesigned.
● Slider Components now have customizable grip-styles (accessible via popup only)
● Slider Components are now 20 pixels wider by default than before.
● Slider Controls now draw focus rectangle to indicate caret capture.
● Slider Control text input is now automatically activated by a keypress when the slider has focus.
● Slider Controls that are locked are now rendered greyed out.
● Tumbler Controls now draw themselves in 3D style when they are focused.
● Tumbler Control text input is now automatically activated by a keypress when the slider has focus.
● Tumbler Controls that are locked are now rendered greyed out.
● Generic Data parameters now allow setting multiple items via the menu.
● Text display has been rewritten for Text Panels and Param Viewers, making it faster.
● Null items in Text Panels are now drawn transparently.
● Empty strings in Text Panels are now drawn transparently as "<empty>".
● Path mapping operations that do not involve List Indices are faster.
○ Point Parameters could not be baked from the toolbar, this is fixed.
○ Negative slider initialization codes would result in erroneous limits, this is fixed.
○ Fixed a bug with the normal vector output of the Spherical Cloud component.
○ ASCII control code characters in strings prevented ghx serialization, this is fixed.
○ Fixed several bugs with ReadFile component custom parser scripts.
○ Fixed a bug (without introducing other ones I hope) with screwed up output data trees in case of partial path overlaps.
○ Empty branches would get skipped by the PathMapper, this is fixed.
○ Transform multiplication was the wrong way 'round, this is fixed.
○ There was (at least one) bug in the Curve Offset direction code, it got fixed.
○ Fixed a bug with the Convex Hull algorithm (while inebriated on Tokaj no less).
Important notes:
The zero-length-slider-ultra-crash may or may not still happen. I've fixed a bug in slider code that may or may not explain why it happened to begin with (though probably it doesn't) and also some safety code. Please let me know if this is still a problem.
All the Set components operate on simple data types only (Booleans, Integers, Numbers, Complex Numbers, Strings, Intervals, Vectors & Points). They will not work correctly on more complex types such as Curves, Meshes or Breps. I do not know if they ever will.
I've tried making the sliders and tumblers (the controls, not the canvas objects) easier to use. Basically it should now be obvious based on the display whether a slider or tumbler has focus. Slider have a dotted rectangle drawn in them when focused, tumblers are drawn as 3D objects instead of flat objects). When a slider or tumbler has focus, just typing should automatically bring up the text input override. Please test that this works as advertised and is not 'weird'.
Note to GHA developers: The Internal_Icon_24x24 property on Components and Custom object is now Obsolete. It still exists for the time being, but you are advised to use the Icon property instead.
--
David Rutten
david@mcneel.com
Poprad, Slovakia…
8.3.0 ************* IDF Context for following error/warning message: ************* Note -- lines truncated at 300 characters, if necessary... ************* 829 Construction, ************* indicated Name=PELLE001 ************* Only last 10 lines before error line shown.....
************* 832 AIR WALL2, !- - Layer 2 ************* 833 X-LAM, !- - Layer 3 ************* 834 POLYSTYRENE2, !- - Layer 4 ************* 835 PANNELLO VIP, !- - Layer 5 ************* 836 POLYSTYRENE2, !- - Layer 6 ************* 837 X-LAM, !- - Layer 7 ************* 838 LANA DI ROCCIAS, !- - Layer 8 ************* 839 VANO IMPIANTI, !- - Layer 9 ************* 840 LANA DI ROCCIAS, !- - Layer 10 ************* 841 LASTRA IN GESSOFIBRA, !- - Layer 11 ** Severe ** IP: IDF line~841 Error detected for Object=CONSTRUCTION ** ~~~ ** Maximum arguments reached for this object, trying to process ->LASTRA IN GESSOFIBRA<- ************* IDF Context for following error/warning message: ************* Note -- lines truncated at 300 characters, if necessary... ************* 985 Construction, ************* indicated Name=ROOF001 ************* Only last 10 lines before error line shown..... ************* 988 TRAVETTI, !- - Layer 2 ************* 989 TAVOLATO, !- - Layer 3 ************* 990 POLYSTYRENE2, !- - Layer 4 ************* 991 PANNELLO VIP, !- - Layer 5 ************* 992 POLYSTYRENE2, !- - Layer 6 ************* 993 X-LAM, !- - Layer 7 ************* 994 LANA DI ROCCIAS, !- - Layer 8 ************* 995 VANO IMPIANTI, !- - Layer 9 ************* 996 LANA DI ROCCIAS, !- - Layer 10 ************* 997 LASTRA IN GESSOFIBRA, !- - Layer 11 ** Severe ** IP: IDF line~997 Error detected for Object=CONSTRUCTION ** ~~~ ** Maximum arguments reached for this object, trying to process ->LASTRA IN GESSOFIBRA<- ** Warning ** IP: Note -- Some missing fields have been filled with defaults. See the audit output file for details. ** Severe ** IP: Possible incorrect IDD File ** ~~~ ** IDD Version:"IDD_Version 8.3.0" ** ~~~ ** Version in IDF="8.3" not the same as expected="8.3" ** ~~~ ** Possible Invalid Numerics or other problems ** Fatal ** IP: Errors occurred on processing IDF file. Preceding condition(s) cause termination. ...Summary of Errors that led to program termination: ..... Reference severe error count=3 ..... Last severe error=IP: Possible incorrect IDD File ************* Warning: Node connection errors not checked - most system input has not been read (see previous warning). ************* Fatal error -- final processing. Program exited before simulations began. See previous error messages. ************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning; 0 Severe Errors. ************* EnergyPlus Sizing Error Summary. During Sizing: 0 Warning; 0 Severe Errors. ************* EnergyPlus Terminated--Fatal Error Detected. 1 Warning; 3 Severe Errors; Elapsed Time=00hr 00min 0.34sec
My question is how i can fix it ??? and why it tell me that:
** Severe ** IP: Possible incorrect IDD File** ~~~ ** IDD Version:"IDD_Version 8.3.0"** ~~~ ** Version in IDF="8.3" not the same as expected="8.3"** ~~~ ** Possible Invalid Numerics or other problems** Fatal ** IP: Errors occurred on processing IDF file. Preceding condition(s) cause termination....Summary of Errors that led to program termination:
Help me pleaseeeeeeee
Happy new year!!!!!…
8.3.0************* IDF Context for following error/warning message:************* Note -- lines truncated at 300 characters, if necessary...************* 829 Construction,************* indicated Name=PELLE001************* Only last 10 lines before error line shown.....
************* 832 AIR WALL2, !- - Layer 2************* 833 X-LAM, !- - Layer 3************* 834 POLYSTYRENE2, !- - Layer 4************* 835 PANNELLO VIP, !- - Layer 5************* 836 POLYSTYRENE2, !- - Layer 6************* 837 X-LAM, !- - Layer 7************* 838 LANA DI ROCCIAS, !- - Layer 8************* 839 VANO IMPIANTI, !- - Layer 9************* 840 LANA DI ROCCIAS, !- - Layer 10************* 841 LASTRA IN GESSOFIBRA, !- - Layer 11** Severe ** IP: IDF line~841 Error detected for Object=CONSTRUCTION** ~~~ ** Maximum arguments reached for this object, trying to process ->LASTRA IN GESSOFIBRA<-************* IDF Context for following error/warning message:************* Note -- lines truncated at 300 characters, if necessary...************* 985 Construction,************* indicated Name=ROOF001************* Only last 10 lines before error line shown.....************* 988 TRAVETTI, !- - Layer 2************* 989 TAVOLATO, !- - Layer 3************* 990 POLYSTYRENE2, !- - Layer 4************* 991 PANNELLO VIP, !- - Layer 5************* 992 POLYSTYRENE2, !- - Layer 6************* 993 X-LAM, !- - Layer 7************* 994 LANA DI ROCCIAS, !- - Layer 8************* 995 VANO IMPIANTI, !- - Layer 9************* 996 LANA DI ROCCIAS, !- - Layer 10************* 997 LASTRA IN GESSOFIBRA, !- - Layer 11** Severe ** IP: IDF line~997 Error detected for Object=CONSTRUCTION** ~~~ ** Maximum arguments reached for this object, trying to process ->LASTRA IN GESSOFIBRA<-** Warning ** IP: Note -- Some missing fields have been filled with defaults. See the audit output file for details.** Severe ** IP: Possible incorrect IDD File** ~~~ ** IDD Version:"IDD_Version 8.3.0"** ~~~ ** Version in IDF="8.3" not the same as expected="8.3"** ~~~ ** Possible Invalid Numerics or other problems** Fatal ** IP: Errors occurred on processing IDF file. Preceding condition(s) cause termination....Summary of Errors that led to program termination:..... Reference severe error count=3..... Last severe error=IP: Possible incorrect IDD File************* Warning: Node connection errors not checked - most system input has not been read (see previous warning).************* Fatal error -- final processing. Program exited before simulations began. See previous error messages.************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning; 0 Severe Errors.************* EnergyPlus Sizing Error Summary. During Sizing: 0 Warning; 0 Severe Errors.************* EnergyPlus Terminated--Fatal Error Detected. 1 Warning; 3 Severe Errors; Elapsed Time=00hr 00min 0.34sec
My question is how i can fix it ??? and why it tell me that:
** Severe ** IP: Possible incorrect IDD File** ~~~ ** IDD Version:"IDD_Version 8.3.0"** ~~~ ** Version in IDF="8.3" not the same as expected="8.3"** ~~~ ** Possible Invalid Numerics or other problems** Fatal ** IP: Errors occurred on processing IDF file. Preceding condition(s) cause termination....Summary of Errors that led to program termination:
Help me pleaseeeeeeee
Thanks and Happy new year!!!!!…
ld be the best UI.
I think difference is made by 'Slider = 10' vs 'Slider = 10.000' more than by simple input/component initialization so, why to stop when it could be even more powerful?
Slider = 0 To 5 --- Slider in [0, 5]
Slider = {3; 0 To 5}
Slider = {3;0;5}
Slider = 3;0;5
Slider = 3 0:5
Slider = 3,0,5
Slider = 3 0 5 --- Value and range (min max)
3 0.0 5 --- 3.0 0.0 5.0
3 0 5.0 --- 3.0 0.0 5.0
3.0 0 5 --- 3.0 0.0 5.0
-1 0 5 --- 0 0 5 (-1 -1 5)
6 0 5 --- 5 0 5 (6 0 6)
Slider = 0:2:6 --- Even numbers: 0, 2, 4, 6.
Slider = 1:2:7 --- Odd numbers: 1, 3, 5, 7.
0:2:5 --- 0:2:4 (or 0:2:6)
3:2:8 --- 3:2:7 (or 3:2:9)
3 1:2:7 --- 1 3 5 7 (value 3)
Bang! = 7 --- 7 outputs
Merge = 5 --- 5 inputs
What's your opinion about Bang! = 7? As it's setting number of inputs, should it use different format? Bang! 7? Bang! (7)? Bang! i7?
+ * - / \ % ^ & | ! = > --- Addition, Multiplication, Subtraction, Division, Integer Division, Modulus, Power, AND, OR, NOT, Larger than, &c.
= could be a problem.
\ Integer division or Set difference?
! could be NOT but also Factorial.
| could mean intersection.
& could mean concatenate.
1+ --- Addition: input A = 1
2* --- Multiplication: input A = 2
+{0,1,1} --- Addition: input B = {0,1,1}
0-, 1/, 2^, 10^, e^ have their own components
Flatten = {7} or Flatten = 7 --- Input P = {7} (off-topic: Why can’t P be a list?)
Pt = {1, 2, 3} --- Point XYZ, X = 1, Y = 2, Z = 3.
Swatch = 129,239,231 (102)
Swatch = 129 139 231 102
F2 = "x^2+y"
"List Length" and "List Insert" don't work properly: "Value List" is choosen. Why? What's the reason to this choice? Well, I'd like to know how the whole thing (search by keywords) works, David.
Name and nickname can be now used as keywords. "Larger" works for ">" but "greater" doesn't. Could it be improved? Could synonyms be used? Could a short description even be used (I know this could be a bit weird)?
more than --- >
more or less --- Similarity
more less --- Similarity
red green --- Sets.List components should be showed
lightning --- Split Tree
What about use Curve.Analysis or Math.Boolean to display those Tab.Panel components? Param, Math, Sets, Vector? Primitive, Special, Util? Tab, Panel, and Tab.Panel as keywords.
At the moment that I write this, I check that ignoring accents in keywords has almost been included (0.8.0009): p`anel, pañel, pánel --- panel (almost)
Shouldn’t 'Dom2' work for Dom²?
What about nested search? You type some keywords (say 'Params' or 'Params.Geometry', or 'red green', or 'lst') and then you make a fine-tunning search over previous results/keywords. Tab.Panel and/or nested geometry could be useful when search by plug-in is desired or when you want to search among .ghuser components (first 'ghuser' or 'Extra.MyPlugIn' or 'lst' keyword and then fine-tunning, specific, search).
Is 'list length' performing this nested search right now ('lst' > 'length')? Anyway, I am thinking about UI (graphical) changes; successive searches.
As I said, description (and even words from the help info) could be used to search. What about "some kind of tags"? I mean that if 'list l' to finally choose List Length has been used for a while, that could be learned. Eventually, an XML file could store these tags, so you could even edit them. That could implement description, name, nickname, help info, Tab.Panel, .ghuser, synonyms (lots of them), tags/shortcuts or wathever.
How could flatten/graft/reverse be used? Initialize graft+Simplify or graft+Bang! could be really useful.
What about expressions? I don't how could it be done properly: would Slider = x^2 (expression) work? I mean, aren't expressions parsed when initializing?
Is Panel somehow doing this? 'panel = wathever' always suppose that wathever is a string, so you can't use 'panel = <pi>'. Sets.Strings components also do this.
I've been about to write several paragraphs about height/width (resizable components: Panel, Graph Mapper, Slider, &c.), input/output names (Scripts, F components; or any component with editable input/output names), orientation (Scribble), type hint and access option, nickname, &c. but, to sum up: being able to set any property when initializing would be really useful. I'd like to know the best choice of syntax but I'm sure that, David, you're closer to the answer. What do you think about this?
Slider: 3 0 5 "MySlider" "Slider^2"
Panel: "This is the content" "This is the title"
VB: "N" List Integer 7 "r" Item Double
Addition: A 1 B 2
I guess that any unified syntax would be elegant and useful, but additional ad hoc syntax (per component) could be even better (cleaner).
What about use lists of values? I'm not sure about format: panel = ("Hello", "Bonjour", "Hola")? If any valid format/syntax is found, maybe more sophisticated fetaures could be achieved: panel = {0;0} ("A", "B", "C") {0;1} ("1", "2", "3") How would you like this to be implemented?
There is a much simpler and interesting feature that would be useful, in my opinion: being able to initialize more than one component. I mean say 7xSlider = 10.0 and get 7 sliders and I also mean multiline (multi-component) initialization: Ctrl+Intro when you want to start a new line and Intro (or even some Accept/Cancel buttons when you activate multiline mode) to initialize (every line/component), for example. I mean:
3 x Slider = 1
Panel
Mass addition
Panel
And the whole bunch of components that were in mind (pre-thinked definition) is initialized. It speeds up the workflow, making more dynamic to add components that are only available via the drop-down panels.
Should this multiplier be something like a text box adjacent to search field more than '7x'?
These are some of my thoughts about intitializing. Please let me know your opinion :]
…
lly it should not make much of a difference - random number generation is not affected, mutation also is not. crossover is a bit more tricky, I use Simulated Binary Crossover (SBX-20) which was introduced already in 1194:
Deb K., Agrawal R. B.: Simulated Binary Crossover for Continuous Search Space, inIITK/ME/SMD-94027, Convenor, Technical Reports, Indian Institue of Technology, Kanpur, India,November 1994
Abst ract. The success of binary-coded gene t ic algorithms (GA s) inproblems having discrete sear ch sp ace largely depends on the codingused to represent the prob lem variables and on the crossover ope ratorthat propagates buildin g blocks from pare nt strings to childrenst rings . In solving optimization problems having continuous searchspace, binary-co ded GAs discr et ize the search space by using a codingof the problem var iables in binary st rings. However , t he coding of realvaluedvari ables in finit e-length st rings causes a number of difficulties:inability to achieve arbit rary pr ecision in the obtained solution , fixedmapping of problem var iab les, inh eren t Hamming cliff problem associatedwit h binary coding, and processing of Holland 's schemata incont inuous search space. Although a number of real-coded GAs aredevelop ed to solve optimization problems having a cont inuous searchspace, the search powers of these crossover operators are not adequate .In t his paper , t he search power of a crossover operator is defined int erms of the probability of creating an arbitrary child solut ion froma given pair of parent solutions . Motivated by t he success of binarycodedGAs in discret e search space problems , we develop a real-codedcrossover (which we call the simulated binar y crossover , or SBX) operatorwhose search power is similar to that of the single-point crossoverused in binary-coded GAs . Simulation results on a number of realvaluedt est problems of varying difficulty and dimensionality suggestt hat the real-cod ed GAs with t he SBX operator ar e ab le to perform asgood or bet t er than binary-cod ed GAs wit h t he single-po int crossover.SBX is found to be particularly useful in problems having mult ip le optimalsolutions with a narrow global basin an d in prob lems where thelower and upper bo unds of the global optimum are not known a priori.Further , a simulation on a two-var iable blocked function showsthat the real-coded GA with SBX work s as suggested by Goldberg
and in most cases t he performance of real-coded GA with SBX is similarto that of binary GAs with a single-point crossover. Based onth ese encouraging results, this paper suggests a number of extensionsto the present study.
7. ConclusionsIn this paper, a real-coded crossover operator has been develop ed bas ed ont he search characte rist ics of a single-point crossover used in binary -codedGAs. In ord er to define the search power of a crossover operator, a spreadfactor has been introduced as the ratio of the absolute differences of thechildren points to that of the parent points. Thereaft er , the probabilityof creat ing a child point for two given parent points has been derived forthe single-point crossover. Motivat ed by the success of binary-coded GAsin problems wit h discrete sear ch space, a simul ated bin ary crossover (SBX)operator has been develop ed to solve problems having cont inuous searchspace. The SBX operator has search power similar to that of the single-po intcrossover.On a number of t est fun ctions, including De Jong's five te st fun ct ions, ithas been found that real-coded GAs with the SBX operator can overcome anumb er of difficult ies inherent with binary-coded GAs in solving cont inuoussearch space problems-Hamming cliff problem, arbitrary pr ecision problem,and fixed mapped coding problem. In the comparison of real-coded GAs wit ha SBX operator and binary-coded GAs with a single-point crossover ope rat or ,it has been observed that the performance of the former is better than thelatt er on continuous functions and the performance of the former is similarto the lat ter in solving discret e and difficult functions. In comparison withanother real-coded crossover operator (i.e. , BLX-0 .5) suggested elsewhere ,SBX performs better in difficult test functions. It has also been observedthat SBX is particularly useful in problems where the bounds of the optimum
point is not known a priori and wher e there are multi ple optima, of whichone is global.Real-coded GAs wit h t he SBX op erator have also been tried in solvinga two-variab le blocked function (the concept of blocked fun ctions was introducedin [10]). Blocked fun ct ions are difficult for real-coded GAs , becauselocal optimal points block t he progress of search to continue towards t heglobal optimal point . The simulat ion results on t he two-var iable blockedfunction have shown that in most occasions , the sea rch proceeds the way aspr edicted in [10]. Most importantly, it has been observed that the real-codedGAs wit h SBX work similar to that of t he binary-coded GAs wit h single-pointcrossover in overcoming t he barrier of the local peaks and converging to t heglobal bas in. However , it is premature to conclude whether real-coded GAswit h SBX op erator can overcome t he local barriers in higher-dimensionalblocked fun ct ions.These results are encour aging and suggest avenues for further research.Because the SBX ope rat or uses a probability distribut ion for choosing a childpo int , the real-coded GAs wit h SBX are one st ep ahead of the binary-codedGAs in te rms of ach ieving a convergence proof for GAs. With a direct probabilist ic relationship between children and parent points used in t his paper,cues from t he clas sical stochast ic optimization methods can be borrowed toachieve a convergence proof of GAs , or a much closer tie between the classicaloptimization methods and GAs is on t he horizon.
In short, according to the authors my SBX operator using real gene values is as good as older ones specially designed for discrete searches, and better in continuous searches. SBX as far as i know meanwhile is a standard general crossover operator.
But:
- there might be better ones out there i just havent seen yet. please tell me.
- besides tournament selection and mutation, crossover is just one part of the breeding pipeline. also there is the elite management for MOEA which is AT LEAST as important as the breeding itself.
- depending on the problem, there are almost always better specific ways of how to code the mutation and the crossover operators. but octopus is meant to keep it general for the moment - maybe there's a way for an interface to code those things yourself..!?
2) elite size = SPEA-2 archive size, yes. the rate depends on your convergence behaviour i would say. i usually start off with at least half the size of the population, but mostly the same size (as it is hard-coded in the new version, i just realize) is big enough.
4) the non-dominated front is always put into the archive first. if the archive size is exceeded, the least important individual (the significant strategy in SPEA-2) are truncated one by one until the size is reached. if it is smaller, the fittest dominated individuals are put into the elite. the latter happens in the beginning of the run, when the front wasn't discovered well yet.
3) yes it is. this is a custom implementation i figured out myself. however i'm close to have the HypE algorithm working in the new version, which natively has got the possibility to articulate perference relations on sets of solutions.
…
.!
Feel free to ignore them, or to remove this thread.
They are just a couple of thoughts:
1st idea: It would be great to right click on a slider and reset it to a "original" value (maybe just a click on a little icon next to the name, so it is even faster).This can be handy when using Galapagos, as all the sliders gets changed...and the fastest way I found so far to reset them is to close and open the GH file.But I bet as Galapagos is so new... well... maybe this is something you already thought about!
2nd idea: Having parametric sliders (with inputs).Imagine you want a slider to vary from x to y... now you have to type in the values. It would be good to set set x and y with inputs.
This is actually very useful using Galapagos, but quite useless in all the other cases...
Probably than the best way to do this is to add a feature in Galapagos to use domains as inputs... but I read somewhere that you are working on this already!
3rd idea: Change the value (or range) of multiple sliders.Imagine you want all the sliders you have to be =2... and imagine to have 20 sliders... if you select them and right click on one, it will only change that one. (not the selection). Would be good to edit a selection. (or maybe there is a way and I don't know it?)
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Well, don't know if that will help somehow, but they are just thoughts! ;)
Thanks if you will consider them!!!
Compliments again for the incredible hard work on GH!
Cheers,Fil…
t file** - ply file with just x,y,z locations. I got it from a 3d scanner. Here is how first few lines of file looks like - ply format ascii 1.0 comment VCGLIB generated element vertex 6183 property float x property float y property float z end_header -32.3271 -43.9859 11.5124 -32.0631 -43.983 11.4945 12.9266 -44.4913 28.2031 13.1701 -44.4918 28.2568 13.4138 -44.4892 28.2531 13.6581 -44.4834 28.1941 13.9012 -44.4851 28.2684 ... ... ... In case you need the data - please email me on **nisha.m234@gmail.com**. **Algorithm:** I am trying to find principal curvatures for extracting the ridges and valleys. The steps I am following is: 1. Take a point x 2. Find its k nearest neighbors. I used k from 3 to 20. 3. average the k nearest neighbors => gives (_x, _y, _z) 4. compute covariance matrix 5. Now I take eigen values and eigen vectors of this covariance matrix 6. I get u, v and n here from eigen vectors. u is a vector corresponding to largest eigen value v corresponding to 2nd largest n is 3rd smallest vector corresponding to smallest eigen value 7. Then for transforming the point(x,y,z) I compute matrix T T = [ui ] [u ] [x - _x] [vi ] = [v ] x [y - _y] [ni ] [n ] [z - _z] 8. for each i of the k nearest neighbors:<br> [ n1 ] [u1*u1 u1*v1 v1*v1] [ a ]<br> [ n2 ] = [u2*u2 u2*v2 v2*v2] [ b ] <br> [... ] [ ... ... ... ] [ c ] <br> [ nk ] [uk*uk uk*vk vk*vk]<br> Solve this for a, b and c with least squares 9. this equations will give me a,b,c 10. now I compute eigen values of matrix [a b b a ] 11. This will give me 2 eigen values. one is Kmin and another Kmax. **My Problem:** The output is no where close to finding the correct Ridges and Valleys. I am totally Stuck and frustrated. I am not sure where exactly I am getting it wrong. I think the normal's are not computed correctly. But I am not sure. I am very new to graphics programming and so this maths, normals, shaders go way above my head. Any help will be appreciated. **PLEASE PLEASE HELP!!** **Resources:** I am using Visual Studio 2010 + Eigen Library + ANN Library. **Other Options used** I tried using MeshLab. I used ball pivoting triangles remeshing in MeshLab and then applied the polkadot3d shader. If correctly identifies the ridges and valleys. But I am not able to code it. **My Function:** //the function outputs to ply file void getEigen() { int nPts; // actual number of data points ANNpointArray dataPts; // data points ANNpoint queryPt; // query point ANNidxArray nnIdx;// near neighbor indices ANNdistArray dists; // near neighbor distances ANNkd_tree* kdTree; // search structure //for k = 25 and esp = 2, seems to got few ridges queryPt = annAllocPt(dim); // allocate query point dataPts = annAllocPts(maxPts, dim); // allocate data points nnIdx = new ANNidx[k]; // allocate near neigh indices dists = new ANNdist[k]; // allocate near neighbor dists nPts = 0; // read data points ifstream dataStream; dataStream.open(inputFile, ios::in);// open data file dataIn = &dataStream; ifstream queryStream; queryStream.open("input/query.
pts", ios::in);// open data file queryIn = &queryStream; while (nPts < maxPts && readPt(*dataIn, dataPts[nPts])) nPts++; kdTree = new ANNkd_tree( // build search structure dataPts, // the data points nPts, // number of points dim); // dimension of space while (readPt(*queryIn, queryPt)) // read query points { kdTree->annkSearch( // search queryPt, // query point k, // number of near neighbors nnIdx, // nearest neighbors (returned) dists, // distance (returned) eps); // error bound double x = queryPt[0]; double y = queryPt[1]; double z = queryPt[2]; double _x = 0.0; double _y = 0.0; double _z = 0.0; #pragma region Compute covariance matrix for (int i = 0; i < k; i++) { _x += dataPts[nnIdx[i]][0]; _y += dataPts[nnIdx[i]][1]; _z += dataPts[nnIdx[i]][2]; } _x = _x/k; _y = _y/k; _z = _z/k; double A[3][3] = {0,0,0,0,0,0,0,0,0}; for (int i = 0; i < k; i++) { double X = dataPts[nnIdx[i]][0]; double Y = dataPts[nnIdx[i]][1]; double Z = dataPts[nnIdx[i]][2]; A[0][0] += (X-_x) * (X-_x); A[0][1] += (X-_x) * (Y-_y); A[0][2] += (X-_x) * (Z-_z); A[1][0] += (Y-_y) * (X-_x); A[1][1] += (Y-_y) * (Y-_y); A[1][2] += (Y-_y) * (Z-_z); A[2][0] += (Z-_z) * (X-_x); A[2][1] += (Z-_z) * (Y-_y); A[2][2] += (Z-_z) * (Z-_z); } MatrixXd C(3,3); C <<A[0][0]/k, A[0][1]/k, A[0][2]/k, A[1][0]/k, A[1][1]/k, A[1][2]/k, A[2][0]/k, A[2][1]/k, A[2][2]/k; #pragma endregion EigenSolver<MatrixXd> es(C); MatrixXd Eval = es.eigenvalues().real().asDiagonal(); MatrixXd Evec = es.eigenvectors().real(); MatrixXd u,v,n; double a = Eval.row(0).col(0).value(); double b = Eval.row(1).col(1).value(); double c = Eval.row(2).col(2).value(); #pragma region SET U V N if(a>b && a>c) { u = Evec.row(0); if(b>c) { v = Eval.row(1); n = Eval.row(2);} else { v = Eval.row(2); n = Eval.row(1);} } else if(b>a && b>c) { u = Evec.row(1); if(a>c) { v = Eval.row(0); n = Eval.row(2);} else { v = Eval.row(2); n = Eval.row(0);} } else { u = Eval.row(2); if(a>b) { v = Eval.row(0); n = Eval.row(1);} else { v = Eval.row(1); n = Eval.row(0);} } #pragma endregion MatrixXd O(3,3); O <<u, v, n; MatrixXd UV(k,3); VectorXd N(k,1); for( int i=0; i<k; i++) { double x = dataPts[nnIdx[i]][0];; double y = dataPts[nnIdx[i]][1];; double z = dataPts[nnIdx[i]][2];; MatrixXd X(3,1); X << x-_x, y-_y, z-_z; MatrixXd T = O * X; double ui = T.row(0).col(0).value(); double vi = T.row(1).col(0).value(); double ni = T.row(2).col(0).value(); UV.row(i) << ui * ui, ui * vi, vi * vi; N.row(i) << ni; } Vector3d S = UV.colPivHouseholderQr().solve(N); MatrixXd II(2,2); II << S.row(0).value(), S.row(1).value(), S.row(1).value(), S.row(2).value(); EigenSolver<MatrixXd> es2(II); MatrixXd Eval2 = es2.eigenvalues().real().asDiagonal(); MatrixXd Evec2 = es2.eigenvectors().real(); double kmin, kmax; if(Eval2.row(0).col(0).value() < Eval2.row(1).col(1).value()) { kmin = Eval2.row(0).col(0).value(); kmax = Eval2.row(1).col(1).value(); } else { kmax = Eval2.row(0).col(0).value(); kmin = Eval2.row(1).col(1).value(); } double thresh = 0.0020078; if (kmin < thresh && kmax > thresh ) cout << x << " " << y << " " << z << " " << 255 << " " << 0 << " " << 0 << endl; else cout << x << " " << y << " " << z << " " << 255 << " " << 255 << " " << 255 << endl; } delete [] nnIdx; delete [] dists; delete kdTree; annClose(); } Thanks, NISHA…