ength is applied to particle b, and the same vector multiplied by -2*BendStrength is applied to a and c
Hope that helps. I was thinking of changing this input slightly for the next Kangaroo release, because I realize it can be a pain if you want bending stiffness of a curve to be independent of the number of points used, but I'll make sure to clarify any changes when I do update this.
…
an that HashCodes well ... since they are "unique" per item (even if this - for the one reason or the other - is created at the same location with that) I barely can see how one can use them in order to get rid if "equal" items (Lines in this occasion).
On the other hand ... well ... using HashSets sampling the Line center and testing length and direction ... well ... this works but why bother? > if you are not doing business with code (thus you need this "check" internally) > use the Kangaroo1 component.
That said the topic of "equality" is rather huge and most people are confusing a lot of things on that matter: for instance a point not equal to another ... well ... that's rather simple but a brep "not equal" with some else ... this is not that easy (if it's solvable).…
te some cut sheets, but not to optmize material, rather define some cut lines. Everything that I am cutting is made of planar wood elements, but there are very specific geometries (mostly straight lines) and I have to put tolerances and radiasas at the corners in order to cut on the cnc mill. Spending time to figure out how to automate is necessary, but I am stuck!
One thing the definition is doing is taking my brep modeled components in rhino and makking them into 2d close curves and laying them side by side. It works...not ideal as its not layed out in a sheet, but that is not the most important part.
Another particular problem is that you will see some notches in the curves, which other pieces will slip into, so different slots need different specific offsets (making them larger) as a toelrance to allow for material play. This I don't even know how to set up so maybe it will just have to wait.
THE MAIN QUESTION, and super important would be, LIFESAVER:
At all 'inward' corners...which I think will always mean concave corners (most are 90 degrees, but are within to sides, instead of a corner sticking out). I'm sure its obviousy, but the reason being the outward corners a circular dril bit can cut, but inward ones need an arc profile extended beyond where the corner of the other piece will fit into. The drill bit i am using is 6mm, so 6mm diamters arcs is what i'm working with.
I have managed to put such an arc at every vertices of each cut piece. The problem being some stick outward isntead of cutting into the piece. So each one needs to be orieneted correctly. Ideally they would also only draw into inward corners, but I can always delete them out. I think maybe I am missing a more logical mathematical way of defining?
For these geometries it is not very important which side the half circle arc in on in the inward corners, but I also have some geometries that I will have to control where the circles face according to the rest of the cut piece.
The cutouts in the middle of the pieces that are curves do not need such corners obviously.
The picture is an example drawn
I hope this isn't too specific and long. in general though automating fabrication, and controling pracitcal math and orientation problems like this is itnersting to me!
THANKS…
perienced with grasshopper, but so far I've managed to combine the following:
Giulio Piacentino's "Catenary arch from height" script
Pirouz Nourian's "Mobius" script (Obtained from a friend)
End Result:
Here's where I'm stuck: I want the mobius twist to revolve around the midpoint of the arch, but the script uses the input values to determine the endpoints, resulting in a weird sinuous shape when viewed from above. Also, the secondary end points (generated by the mobius script, determining the width of the surface) are generated by default along the z axis, resulting in an arch that only touches the "ground" at two points. I attempted to work around this issue by trying to force the zHeight parameter to correspond with the y axis (thus rotating the arch 90 degrees so it would lay "flat"), but the script interprets the third point as a value and not as an actual point to bisect. I thought this might be an issue with the C# component that I obtained from Giulio Piacentino's script, so I attempted to tinker around with the source code. Unfortunately, I'm not fluent in C# so I only managed to mess everything up (I've since recovered the code from the cache). Anybody got some ideas? -BC …
onsidered period.
Even if the end of July for the mediterranean climate is not the best period to perform an adaptive comfort analysis (it's just a pretest to define a LB model) I want to refine the Adaptive comfort Chart (AC) by changing the external air temperature data imported from the .epw file with that of monitored data as reported here below:
Where the monitored ext air temperature are in this form (green panel below):
I have used the comfortPar component to set the following parameters:
Adaptive chart as defined by EN 15251
90% of occupants comfortable
the prevailing outdoor temperature from a weighted running mean of the last week
fully conditioned space (even if it is not properly in line with AC as already discussed)
The question is this: the AC component could correctly apply the code below if there is only a list of external temperature data for a restricted period (without indication about the limits of this period) and not for an entire year?
else: #Calculate a running mean temperature. alpha = 0.8 divisor = 1 + alpha + math.pow(alpha,2) + math.pow(alpha,3) + math.pow(alpha,4) + math.pow(alpha,5) dividend = (sum(_prevailingOutdoorTemp[-24:-1] + [_prevailingOutdoorTemp[-1]])/24) + (alpha*(sum(_prevailingOutdoorTemp[-48:-24])/24)) + (math.pow(alpha,2)*(sum(_prevailingOutdoorTemp[-72:-48])/24)) + (math.pow(alpha,3)*(sum(_prevailingOutdoorTemp[-96:-72])/24)) + (math.pow(alpha,4)*(sum(_prevailingOutdoorTemp[-120:-96])/24)) + (math.pow(alpha,5)*(sum(_prevailingOutdoorTemp[-144:-120])/24)) startingTemp = dividend/divisor if startingTemp < 10: coldTimes.append(0) outdoorTemp = _prevailingOutdoorTemp[7:] startingMean = sum(outdoorTemp[:24])/24 dailyRunMeans = [startingTemp] dailyMeans = [startingMean] prevailTemp.extend(duplicateData([startingTemp], 24)) startHour = 24
…
th one element which is a list of 10 numbers?
I can flatten it and get (I think) a list of 10 elements (even though when I hover over the output of "Flatten" it says "Tree(T) as tree"). I'm surprised I can flatten at all what would appear to common sense to be a simple list of 10 numbers.
I'm hoping that if I can get this answered it will become obvious why we have trees of lists rather than just lists of lists as you would in most computer languages. That's my real goal - to understand the purpose of adding what seems like an unnecessary complication - trees - to the concept of lists in GH. It seems to me as though a "tree" is just a list of other "trees" until you get to the leaves where you can have "lists" which are identical to trees but can have something other than a tree in them. Whether you can have lists of trees or trees with no lists I'm unclear on. Do the leaves of trees have to be lists? Do lists have to be contained in trees? It would appear from the series example where a tree is produced for no obvious reason to contain the list that this is the case but given that you can flatten it, I guess not - or is the "List" I see in the param viewer just another type of "tree"?
I've found many tutorials that talk about how to manipulate trees and lists and I've managed to get along fairly well with them so far, but nothing seems to explain the reasoning behind the existence of trees and the philosophy for how and when they should be used and when lists should/could be used and precisely what the difference is between them.
Sorry to be long winded but I'm so confused!
Darrell Plank
P.S. I've seen David Rutten's diagram with the colored leaves in Grasshopper Primer 2 and that seems helpful. It would appear that trees can only have lists at their leaves and lists can't have trees although I'm not sure that it comes out and says that directly but at least there are no examples of this shown in his tree diagram. I thought I had it down pretty much so decided to test myself. Apparently I'm as confused as ever:
It certainly appears to me that this tree has two levels - a first level with one limb and a second with 10 limbs - and that I should be able to index it with {0;0} and retrieve a tree with one item in it - the list {0}. The panel data seems to confirm this with indices of {0;0;0}, etc. so I put this path in with quite a bit of confidence that it would work and...bust. The error reads "Path {0;0} does not exist within this tree". Huh? Again, I'm just so confused.…
Added by Darrell Plank at 12:17am on January 20, 2015
(twice the amount of lines, it'll take twice as long).
If you nest two loops you're iterating over each line, and then you iterate again over each line. So when you now have twice as many lines, it takes four times as long O(N*N) or O(N²)
With an octree you can reduce the second iteration from O(N) to O(log N). The reason octrees are fast is because they allow you to quickly reject large amounts of lines in your set. Lines are no longer stored in a list, but rather in recursive spatial buckets. If we determine that a certain bucket is too far away to possibly yield any valid results, we can instantly skip all the lines in that buckets and any sub-buckets. If you're lucky, you can reject ~85% of the local data in every iteration, which means even large collections of lines are reduced to only a few potential candidates very quickly.
Thinking about this I'm actually not sure now whether lookup in my Tree3d class is O(log N) or O(sqrt N), but the basic principle holds. The reason the resulting algorithm is O(N * log N) is because the outer loop is still O(N) but the inner loop is now replaced with an O(log N) searcher, so you end up with O(N) * O(log N) = O(N log N)
At least that's how I think it works, computational theory has never been my strong suit.
--
David Rutten
david@mcneel.com
Poprad, Slovakia…
Added by David Rutten at 4:55pm on November 29, 2012
p; 3D Urban ModelingOn the topography subject I get the next message: "One or more boundaries may be outside the bounds of the topo dataset" I'm not sure if it's the .IMG file I'm loading since I found so many IMG files nearing my polyline area (Miami Lat:26 Lon:-81 aprox.) or maybe my polygon doesn't match the topo area? I have no idea why it isn't working :(On the Shapefile subject, haven't been able to find a Building Height SHP File, so far have downloaded around 8 SHP files which only contain Polylines, my solution is to meanwhile randomize Z heights, but of course this data is not "technically" correct.P.S.: I've already tried all example links and also the ones posted by you and Benjamin in this video.Been strugling last few days, hope you can help me, thanks in advance!!…