I'm looking for a one-way hashing/compression algorithm wherein I can stuff many objects (representing days checked off on a calendar, so could be represented as integers) into a fixed length data field.
- I will not need to retrieve them.
- But I will need to test if a particular value was stuffed into the hash.
- I will need to be able to update the hash with more Dates/integers after initial creation.
- Finally it would be great if an implementation already exists as a Javascript library.
- It's ok if collisions are possible as long as they are quite rare.
Any suggestions? Is this possible? Thanks!
Edit: looking for suggestions on simple easy to use wallets, gift card companies etc.
And to clarify, I mean "shut down early while still producing a fully function and not corrupted output file". Obviously this will stop tar sooner one way or the other.
In case it matters, the compression function is 7za. Also, this is run in WSL (the Ubuntu variety). Ill post the exact code used to call this at the end.
Basically, I want to do this because I significantly underestimated how much data was in the directory this was run on. So far it has chewed through ~200gb of data, and it has at least that much left to go. I have enough space, Im just concerned about something causing the function to about early and losing a days worth of compressing (or more) (this could include, say, windows deciding it was going to restart for an update whether I wanted it to or not). As such, breaking up the remainder into parts ensures that if any time is lost it wont be days worth.
The exact function call is part of a rather leangthy function I have for automating tar->compress and decompress->untar operations, but I believe the function call is as follows:
tar cvf - -O --verbose --keep-newer-files --totals --checkpoint=1000 --full-time --preserve-permissions --show-omitted-dirs --show-transformed-names --restrict --exclude="$excludeString" "$inputDirectory" | 7za a -t7z -m0=LZMA2 -mx=9 -mt=on -ms=on -mtc=on -mhc=on -mf=on -ms=on -md=128m -mmf=bt4 -mfb=128 -ma=1 -mlc=4 -mlp=0 -si "$outputFilename"I've been coding my way through A Hithchhiker's guide to 'Fractal-Based' Function Approximation and Image Compression and was wondering if anyone had some experience with this. The functions described in the paper are in a file called HGF.py and the examples are in this file. My specific questions are;
In the two dimensional IFSM the functions are appended to a list for every pixel in the input image. On a one dimensional IFSM I just said,
fnlist[n] = lamda x:fnlist[n](x) + new_fn(x)
but when I tried IFSM2d with an IFSmap of 8 functions I had recusion errors. so how should I deal with the elements of the graph with multiple functions. On page 15 the article says,
import Image
tomimg = Image.open(file('lena.jpg','rb'))
tomimg.load()
tr,tg,tb = tomimg.split()
then,
Parent_block = [[(i+k,j+l) for k,l in itertools.product(range(16),range(16))] for i,j in itertools.product(range(0,trdata.size[0],16),range(0,trdata.size[1],16))]
child_block = []
for i in Parent_block:
child_block.append([i[:int(len(i)/4)],i[int(len(i)/4):int(len(i)/2)],i[int(len(i)/2):int(len(i)/2)+int(len(i)/4)],i[int(len(i)/2)+int(len(i)/4):]] )
converted to data for ISFM2d like,
uxm = map(tr.getpixel,child_block[0][3])
uxm = [uxm[i:i +8] for i in range(8)]
So whats my next step, how do I determine my theta functions? Do I resize and compare the difference between gray maps?
Male, 30 years old, otherwise healthy. I'm prone to boils and have got a half-inch one on my thigh with a one inch radius red area around it that is ever so slightly raised. Trying to follow the home remedy of using a hot compress to bring it to a head. My issue is that the towels I use cool off too quickly to be called a "hot compress" for long. Would a shower function the same way, or must the heat be localized?
local function test(...) return ... end
print(test(1, 2, 3), test(4, 5, 6), test(7, 8, 9))
-- expected: 1 2 3 4 5 6 7 8 9
-- got: 1 4 7 8 9 🤔
This is the best I have come up with (very similar to tdismount's solution):
local function tables2vararg(...)
local combined = {}
for _, tables in ipairs{...} do
for _, values in ipairs(tables) do
table.insert(combined, values)
end
end
return unpack(combined)
end
print(tables2vararg({test(1, 2, 3)}, {test(4, 5, 6)}, {test(7, 8, 9)}))
I have 156 images and want to have 3 image sequences, one is 75, one with 75 and the other with all of them.
Right now I have to upload all the images multiple times and create multiple image sequences. I would like to just upload the images one time and have multiple image sequences from the same textures. Is this possible?
I saw a post here on reddit not too long ago where this was brought up briefly. Are there any other practical processes where a solid/liquid is compressed in a similar way? Or is the nuclear weapon example the only one? Could you possibly do this to a chunk of steel and force it to be more dense and use it for armor as an example?or would you just get a bomb?
Also, if we did this to a piece of steel how would it affect its properties other than changing its density?
