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steerablesafe commented on Tell HN: Adobe took down the PDF 1.7 specification from their site    · Posted by u/steerablesafe
zozbot234 · 4 years ago
PDFs can support tables of contents with labeled chapters and sections. Not sure if the feature is standardized, but it's there.
steerablesafe · 4 years ago
The specification does have a hierarchical outline, and you can click on cross references too. Of course navigation can still be cumbersome, linking to chapters can also be awkward (tip: right click on outline element and copy link works in Firefox).

There are some problems of the spec though, and navigation is not the most pressing one. The spec is huge, support for less used parts is spotty in various PDF readers. It also has inaccuracies (not corrected in errata) and underspecified parts.

steerablesafe commented on Tell HN: Adobe took down the PDF 1.7 specification from their site    · Posted by u/steerablesafe
darrenf · 4 years ago
Oh, mea culpa. Honestly I just found the opening page and didn't notice it needed payment to get to the rest of it. I naively assumed that since Adobe had published it with ISO's permission, it was free in both places.
steerablesafe · 4 years ago
No worries! How did you find the "opensource.adobe.com" link? I can't hit it with google, even with aggressive searches like "site:opensource.adobe.com filetype:pdf". And I can't seem to navigate there from the main page.
steerablesafe commented on Tell HN: Adobe took down the PDF 1.7 specification from their site    · Posted by u/steerablesafe
darrenf · 4 years ago
It's still available at this Adobe URL: https://opensource.adobe.com/dc-acrobat-sdk-docs/standards/p... "As distributed by Adobe after adoption as ISO 32000-1:2008, with permission of ISO." [0]

Not to mention ISO unsurprisingly host it, which I would also consider authoritative: https://www.iso.org/obp/ui/#iso:std:iso:32000:-1:ed-1:v1:en

[0] https://www.loc.gov/preservation/digital/formats/fdd/fdd0002...

steerablesafe · 4 years ago
Ah, thanks for the link. For some reason that link doesn't turn up in google search for me, however hard I try. Of course the ISO one is also authoritative, but not free.
steerablesafe commented on Difftastic: A diff that understands syntax   github.com/Wilfred/diffta... · Posted by u/tempodox
steerablesafe · 4 years ago
What would be also cool is a syntax aware custom merge driver for git, but that's probably even harder.
steerablesafe commented on Down the mechanical keyboard rabbit hole   fowlie.github.io/2022/02/... · Posted by u/fowlie
dvdkon · 4 years ago
When using a mouse to the right of the keyboard, a narrower keyboard results in a more natural hand position.

It also helps when you need desk space for things other than computer use, but I admit that benefit is marginal.

steerablesafe · 4 years ago
You can have the numpad on the left, but I rarely saw keyboards like that. I saw some odd "left-handed" rubber dome keyboards, but that's it. You can also have a distinct numpad and put it anywhere.
steerablesafe commented on Xdm – Powerfull download accelerator and video downloader   github.com/subhra74/xdm... · Posted by u/maydemir
charcircuit · 4 years ago
Software can't give you faster download speeds. If I get 10 Mbps down from my ISP I'm not going to somehow download at 50 Mbps. yt-dlp, steam, and firefox already max out my connection when they download something.
steerablesafe · 4 years ago
Sometimes the bottleneck is on the server end, and often they throttle throughput per connection. Some download mangers allow you to download the same file through multiple connections and range request. Having said that I think it's a little bit rude to work around the intended throughput limitation.
steerablesafe commented on Xdm – Powerfull download accelerator and video downloader   github.com/subhra74/xdm... · Posted by u/maydemir
steerablesafe · 4 years ago
I recommend aria2 for a similar purpose. Just `apt install aria2`. I'm just a happy user.
steerablesafe commented on Show HN: PDF API – Generate, convert, and modify PDF documents    · Posted by u/arkgil
steerablesafe · 4 years ago
From the pricing page, limits seem to be on number of documents, not number of pages. Is the number of pages per document also limited?
steerablesafe commented on Make a Fair Coin from a Biased Coin (2018)   xarg.org/2018/01/make-a-f... · Posted by u/leonry
eru · 4 years ago
> One obvious drawback is that you have to flip the coin a 1000 times to produce the first unbiased random bit, while Neumann's method starts producing bits much earlier.

Definitely. Though you could fix that problem relatively easily.

I think you might even be able to run von Neumann's method first, but store the coin flips; and then once you've got enough stored, extract a few more bits from the already used flips.

Perhaps like this:

When you do two flips, you add one of three possible tokens to your list:

'double-heads', 'double-tails' or 'mixed'.

Crucially, you only store 'mixed' and not whether it was 'head-tails' or 'tails-heads' because that information was already used to produce the von-Neuman-bit.

After your list has 1000 entries, you run an algorithm a bit like what I originally described to extract bits. The complication is that the table you construct has all possibilities of shuffling a fixed number of 'double-heads', 'double-tails' or 'mixed' tokens.

steerablesafe · 4 years ago
It feels like an awkward middle ground. Like this method has a limited entropy output for the first 2000 coin flips (first 1000 double-heads/double-tails/mixed entries), and then suddenly it adds back a ton of lost entropy.

An other commenter linked to some papers for asymptotically optimal entropy generation, I wonder if there is more of a streaming method there. It feels like there has to be, even maybe after a slow start. My naive intuition is that after 1000000 coin flips you have a good idea what p is, and then you can basically do arithmetic coding from there. Of course a theoretically correct method can't do exactly this, but it might asymptotically approach it.

u/steerablesafe

KarmaCake day1269January 30, 2020View Original