ow do you sort data trees with distinctive number of list items in each branch?
In this example, there are 161 branches with three distinctive number of list items, 3, 4, and 5. I want to know if there is another way to sort out this data tree into this way: 3 vertices {0;0}, {0;1}, {0;2],...4 vertices {1;0}, {1;1}, {1;2},... 5 vertices {2;0}, {2;1}, {2;2},...
2. Is there a way to sort our surfaces based on number of distinctive list items automatically? For example, if there are surfaces with 3, 4, 5, 6, and 7 vertices, I want to make five branches with the same number of vertices automatically.
I hope my questions make sense...
Thank you!
Dongyeop …
Added by Dongyeop Lee at 12:14pm on October 3, 2016
I get it. I have 11 and 18 as boundaries and 7 to always add 1
But it doesn t seemt to work with the Loop set to False.
Am I doing something wrong?
Thanks,
Dimitris
g definition but in diva for grasshopper in material it just appear dusty_med and not metal_railings and metal_treads. How I should write the correct definition?
void brightfunc dusty_med4 dirt dirt.cal -s 101 .25
dusty_med metal metal_railings005 .7 .7 .7 .3 .2
dusty_med metal metal_treads005 .5 .5 .5 .3 .2…
13;2} ... 20.{13;12}
21. {21;0}22. {21;1}23. {21;2} ... 41. {21;20}
42. {34;0}43. {34;1}44. {34;2} ... 75. {34;33}
76. {55;0}77. {55;1} ... ....
I want to grab the first 8 [0-7], the next 13[8-20], the next 21[21-42] etc
so i have the (known fibonacci seq) list of numbers on the left here:
C S
8 0
13 8
21 21
34 42
55 76
89 131
144 220
233 364
and i need the list on the right, so that i can select items using a Series (N=1 and S and C from the list above) and a List Item component.
the simple question is:
is there a component that can take a list and accumulate it in this way that I need?
if not, is there anyone that can point me to a simple relevant VB example so i could easily adapt it?
many thanks,
gotjosh…
t, let's talk about randomness. Randomness is a problem in computing because digital computers are deterministic. If you give them the exact same instructions they always end up with the exact same result. It turns out to be mathematically impossible to generate true random numbers using a digital computer, but it is fairly easy to generate pseudo-random numbers. This is actually not bad news as pseudo-random numbers -unlike real random numbers- can be generated again and again and you'll end up with the same random numbers every time. Being able to get the same random numbers on demand increases the reliability of these number sequences which in turn makes them easier to use.
Pseudo-random numbers are numbers that have certain characteristics. Note that when we talk about random numbers we are really talking about numbers. Plural. It's easy to generate only a single one, as xkcd so eloquently put it:
So what are these characteristics that define pseudo-randomness? Without being actually correct, I can sum them up as follows:
The sequence of generated numbers should never repeat itself*
The numbers in the sequence ought to be spread evenly across the numeric domain**
There are a lot of different algorithms out there, some better than others, some faster than others, some solving very specific problems while others are more generic. The generator used in Grasshopper is the standard Microsoft .NET Random, based on Donald Knuth's subtractive algorithm.
So let's imagine we want random integers between 0 and 10. What would a bad random sequence look like?
3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 (about as bad as it gets)
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 (not random at all)
1 3 2 5 3 9 1 2 4 2 5 1 1 2 8 1 5 2 3 4 (too many low numbers)
2 8 4 6 0 9 8 2 4 8 6 4 2 2 5 1 4 8 6 2 (too many even numbers)
So what about good sequences? Well, here's a few:
6 9 1 2 0 4 2 8 5 7 2 9 1 9 2 5 3 1 9 2 (sure, why not)
6 2 5 3 4 1 9 7 8 0 2 1 6 4 5 8 9 5 0 9 (looks about right)
1 8 5 2 3 4 5 7 9 5 2 1 0 2 1 0 9 7 6 4 (I suppose)
9 0 6 4 8 3 1 5 2 7 6 1 4 6 0 1 9 7 5 6 (whatever)
There are a lot of valid pseudo-random sequences. (Seriously, loads). So even if we have a good pseudo-random generator we may be given a random sequence that isn't entirely to our liking. The shorter the sequence we need, the more likely it is that statistical aberrations invalidate that particular sequence for us. What we need is some control over the generator so we don't just get a repeatable sequence, but a repeatable sequence we actually like.
Enter seed values. The random generator requires a seed value before it can generate a random sequence. These seed values are always integers, and they can be any valid 32-bit integer. Every unique seed value results in the same sequence. Every time.
Unfortunately there is no clear relationship between seeds and sequences. Changing the seed value from 5 to 6 will result in a completely difference random sequence, and two sequences that are very similar may well have to wildly different seeds. There is therefore no way to guess a good seed value, it is completely trial-and-error. Also because of this extremely discontinuous nature, you cannot use tools like Galapagos to optimize a seed value.
If you are looking for a pseudo-random sequence which has custom characteristics, you may well end up having to write your own generator algorithm. Ask questions about this on the Grasshopper main forum or the VB/C# forum.
Conclusion: Seed values are integers that define the exact sequence of pseudo-random numbers, but there's no way of knowing ahead of time what sequence it will be and there's no way of tweaking a sequence by slightly changing the seed. Even the tiniest change in seed value will result in a radically different random sequence.
--
David Rutten
david@mcneel.com
Poprad, Slovakia
* This is not actually possible. A finite amount of numbers always repeats itself eventually.
** This should only be true for long enough sequences, short sequences are allowed to cluster their values somewhat.
Interesting links for further reading:
Coding Horror: Computers are Louse Random Number Generators
StackOverflow: When do random numbers start repeating?…
Added by David Rutten at 9:52am on October 20, 2012
shift. I realize I can use 'replace branch' but I do not have an available mask to utilize. I have simplified the problem to its simplest form so my question is understandable, however, the tree I am trying perform this operation on is a much larger 3 digit path address.
{1;3;2}
{2;3;4}
{3;5;4}
{4;3;7}
Change the above list to the list below.
{0;3;2}
{1;3;4}
{2;5:4}
{3;3;7}
I wish for a more robust arsenal of branch manipulation components. Most of the things I need to do are possible with the existing components, however, many operations take several components to perform even simple manipulations. Since branch/path manipulation is so integral to using GH successfully, it seems the GH community would be well served by enhancing the available path manipulation components.
Thanks,
Stan
…
l at each point intersection, less 14. align holes to common angle between each 2 points of intersection (so ovals align with curve)5. copy 4. 360/60 about center circle (creates 6 curves rotated thru 360)6. it appears there a 3 more sets of curves that need to be taken care in the same way as 1 thru 4 (see colander pic)6. project the oval patterns onto, 1/2 a sphere somewhat larger that the surface circle, to avoid extreme oval distortion.7. needs some Boolean subtraction of holes from sphere surface
Does this simple road map have some merit?
…