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susi22

1,891 karma · joined March 17, 2013

Email: anonymousmd55 at gmail
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susi22··on Iconic: Advanced icons for the modern web
You don't need a GUI or expensive programs to make very stunning and impressive graphics. I've coded SVG manually myself (using Jade templates) and I've written TikZ and asymptote and it works very very well. Remember, we are programmers and not graphic designers who need Illustrator since they often don't code.

Check out some stuff they do over at tex exchange:

http://tex.stackexchange.com/questions/tagged/tikz-pgf

You can also easily take existing SVG and extract the curve formats out, normalize them and integrate them in your project as a few arrays. You wouldn't start from scratch and have to redraw the github logo. You just put it into source code and things such as arrows you can draw with a few commands

susi22··on Iconic: Advanced icons for the modern web
I didn't mean to say Illustrator is bad b/c of the not openness but more because of the file format. Icons ---compared to other projects done with Illustrator--- are extremely simple and we could use simpler tools instead which means we can use a programming language (an appropriate one, not python etc) to define the languages.

As long as we have the source and it is readable (hence my wish to use a DSL) people will contribute to it with pull request. The result of the kickstarter will not be contributable (except by a small fraction of people)

This can give you a slight taste of a well done DSL which can produce EPS:

http://www.piprime.fr/developpeur/asymptote/example-asy2d/ge...

http://marris.org/asymptote/

Asymptote also knows structs and overloading

susi22··on Iconic: Advanced icons for the modern web
We need to stop making "open source" icons which aren't actually open source. Illustrator files are not open enough so that many people can contribute or edit it to their liking. Look at the FontAwesome github issue page and see how many open issues there are vs how many pull requests have been sent. Not many, since few people have Illustrator.

What we need is a DSL (some already exist) and a framework which defines shapes and forms and which can easily plug things together. Ie. we have _only_ code for all the icons and with a simple "make" run we get our customized sizes, colors, formats etc..

I've actually worked with Asymptote [1] a lot and it would be very easy (and elegant) to define them in that framework. Another candidate would be Scala who can define DSL's elegantly and could use many existing libraries to put out th EPS. It's sad that people invest $50k on something that is again flawed: Not editable, not open (truly) sourced, not line-based versioned (git).

I've been wanting to start something along this way ever since I saw fontawesome but I don't think I have the time to invest. Maybe some day...

[1] http://asymptote.sourceforge.net/

susi22··on GitHub: a case study in link maintenance and 404 pages
Github can definitely improve on this. For instance, if I want to edit a file like so:

https://github.com/takezoe/gitbucket/edit/master/README.md

you will see a 404 if you're not logged in with no information.

susi22··on Prismic.io: a developer-focused approach to content management
Thanks for the link and research. Some of the text is #acb2b6 which is really difficult for me to read. It's not like this website is particularly bad. I've hold back on commenting before but I guess I just felt like ranting today.
susi22··on Prismic.io: a developer-focused approach to content management
Another gray font on gray background website. I think I'll just give up and order a new monitor. I can't read all these new fancy websites. I get it that developers have usually good monitors, but is it really necessary to use a light gray on a gray background?

Edit: Hold your downvotes, I'm talking about the website. Not the blog! The website does have some hard to read gray-on-gray.

susi22··on How traffic actually works
I have to correct myself: Yes you're correct. I thought that the top left blinking arrow indicated that a car passed but that's very wrong. It's just displaying the road construction arrow and the rate or cars is indeed about twice as high.
susi22··on How traffic actually works
Cars per second are the same. Open the two gifs next to each other. Each has 8 frames and the top right lamp is on for 4 and off for 4.
susi22··on How traffic actually works
I just read some of your older blog posts. They're close to my research and well written and very informative. Keep up the good work!

Cheers

susi22··on How traffic actually works
I'm sorry. I didn't mean to lay out any "theory". I really just meant to criticize. I'd suggest to just stick with the theories that researchers have come up with and improve upon them.
susi22··on How traffic actually works
I'm sorry for the harsh critique. I think new radical ideas are great and people should question everything that's out there. But this way was not thought out well enough IMO.

I hope you keep it up and maybe have a follow up post where you can fix some of the flaws.

Some of your ideas are correct and noble. But always remember to take into account the real world driver and his/her behavioral flaws.

Few thoughts: Interesting would be a stochastic behavior model of drivers + driving strategies and in connection with red lights, accidents, rush hour to see what happens. Thought, that model would be quite some work in python.

Cheers

susi22··on How traffic actually works
Agreed 100%

I'm sorry if my post was confusing. I didn't really mean to go to infinity with my theory. I really only wanted to point out the flaws of the article. I didn't mean to say that traffic jams can be avoided. I simply disagree heavily with the author and agree with what's been out there in traffic theory for decades. Part of what you described well in your post!

Again, I'm not suggesting anything radical or want to emerge a new theory. The existing ones are good. I'm just trying to point out flaws from the OP.

susi22··on How traffic actually works
Thank you for that comment. You're 100% correct. However, it again shows that it's important to distinguish between theory and practice:

IF your model is correct, the traffic jam will clear since everybody will at some point reach their desired speed of approx ~80mph again. However, the reality is differnt. The model doesn't work since people break. That's the thing that makes your "deductive thinking practice" break down: People break. To prevent this....

Wait, let me just link this:

http://www.smartmotorist.com/traffic-and-safety-guideline/tr...

susi22··on How traffic actually works
You're right. But in case of a traffic jam we operate at speeds that allow us to do this. Look, the Article's author actually mentions it too:

Quote:

"The difference between these is negligible at high speeds, but at a low enough speed, it becomes difficult to maintain a 2 second following distance from the front bumper of the car in front of you without impinging on the rear bumper of the car in front of you, especially if said car is more than 0 feet long. So under these circumstances the flow rate of the highway decreases below 1 car every 2 seconds — maybe to 1 car every 5 seconds. So now you have to wait 5 seconds for every car in front of you in line."

There you have it. We have plenty of space/time to play with in case we're in a traffic jam since we approach very very slow speeds.

Obviously I'm not saying you should stay 10ft behind somebody when going 80mph.

susi22··on How traffic actually works
This article is so horribly incorrect and fails right at the very beginning with the wrong assumptions and a idea that isn't thought through. What the author forgot is to take by far the most important variable into account: SPEED

So let's quote the author:

"The important fact: there is a limit to the number of cars that can pass by a given point on the highway in a given amount of time, and that limit is one car every 2 seconds, per lane. So imagine you are in heavy traffic during rush hour. There are a certain number of cars in line in front of you. Let’s pick a point on the road to call the front of the line — say, the point at which you plan to exit the highway. The line gets shorter by one car every 2 seconds. If there are 1,000 cars in front of you, it’s going to take a minimum of 2,000 seconds for you to get to the front of the line. It doesn’t matter whether people are kind and let cars merge in front of them, zipper-style. It doesn’t matter how much stop-and-go there is. The simple fact is that it takes 2 seconds per car for you to get to the front of the line, and there are some cars in front of you that have to get there before you do."

Ok this is correct. BUT: I don't care if it takes me 2,000s if my exit is 44 miles away (80mph) but I do if my exit is 10miles away.

So you drive along at 80mph and there is cars around you everywhere. Do you care? No, you're covering distance. It's the same as if you were all by yourself on the highway. The distance between cars is absolutely irrelevant and so is the time between cars if you still go 80mph. Nobody would call it a traffic jam.

Next quote:

"Leaving space in front of your car for people who are trying to merge won’t solve anything."

Yes it absolutely does. And it again solves one very very important piece of a traffic jam: Average speed. Leaving space is crucial. It allows people to do two things:

- Accelerate

- Not having to brake

These two are crucial to get speed up and thus resolve traffic jams. Incidentally he linked an article which visualizes exactly this:

http://www.smartmotorist.com/traffic-and-safety-guideline/tr...

(Section: Merging-lane Traffic Jams, A Simple Cure)

You can see on the right side how his "cars per second" is _exactly the same_ than on the left side. Yet, everybody will be much happier on the right side. Why? Because the speed's been increased and people in the cars cover ground.

Next quote:

"Suppose you’re on a 2-lane (each way) highway and one lane is closed up ahead due to construction. Now the flow rate of your lane is cut in half (or there are twice as many cars in line in front of you, depending on how you want to look at it). Road signs commonly ask you to use both lanes up to the point of the bottleneck. That’s reasonable advice, but it’s not going to get anyone home faster"

Yes it absolutely does. Why? We are all programmers here so let's talk in our lingo: This is our API. Our interface that we agree on. If people follow the interface (rule), then we have people agree on it and we are predictable and prevent braking. This is exactly what we want. Increase speed (with gaps), prevent breaking, be predicable. No surprising cars merging means no breaking and thus increase in average speed which in turn means no more traffic jam.

Please, disregard this article. The conclusions are wrong, the assumptions are wrong and the deductions and the terrible advice he gives at the end is wrong.

susi22··on RethinkDB 1.10: multi-indexing
They settled for the name since MongoDB calles it "Multi-key" index.

Most people would probably not be familiar with the name "inverted index".

susi22··on Reveal.js
It's impressive. But I think it's too much and distracts from the content. Use animations wisely!

Use animations to explain concepts & context but don't make the animations your presentation!

susi22··on Revealed: Qatar's World Cup 'slaves'
I'm glad this is getting attention. I was in Germany in July and watched a ~1h documentary about the working conditions there. Confirming what is written in the Guardian. The image I saw in the documentary were extreme. No access to clean water, no access to working bath rooms, no paying. They're also lured into coming there being promised a better life and once they're there they realize it but it's too late.

There has also been a report on it in March from Spiegel:

http://www.spiegel.de/sport/fussball/wm-2022-internationaler...

I usually dont' quote BILD, but they say the workers get paid ~0.78 Cent (EUR) an hour:

http://www.bild.de/sport/fussball/wm/arbeiter-werden-wie-skl...

No air conditioning when it's often over 50 deg. celsius (~122 Fahrenheit). This could explain the many hear failures noted in the article.

susi22··on What's the Most Concave State in the U.S.? Using R to Solve a Geography Puzzle
Spelling has strict definitions too. You can't just make up spelling. SCNR
susi22··on More On Gmail’s Delivery Delays
We use email communication for our help ticket systems and all our users were affected (~20k). At

9am it was ~10min delay.

10am about 21min

noon about 1h

3pm emails with ~3h delay arrived.

Then it got better. We werent' able to help our users and they of course blamed that we responded slowly. Actually a bounce message would've been preferable since then they could've used a phone or stopped by.

You don't really expect your company @example.org to take 3h. Either bounce withing ~3-4min or you expect it to be delivered by that time.

susi22··on Spain's new piracy penalty: Six years in jail
Can you revise your comment? I can't understand it.
susi22··on Cmd.fm
I'd love to get these implemented:

- Ctrl + L

- 'w'

- 'ls'

susi22··on A Rally Against Mass Surveillance in Washington, DC
I'll ride the megabus in from my campus. Cheers
susi22··on We need to stop masking passwords
We aren't even save from this:

http://www.cs.berkeley.edu/~tygar/papers/Keyboard_Acoustic_E...

but then we should just show the passwords on the screen we enter? That's just insane. Linux command line doesn't even show a * when entering a password. That's how it should be.

We should be paranoid about passwords and not display them.

susi22··on Command-line tools for data science
This also really helpful (pity it's relatively unknown):

https://github.com/dbro/csvquote

And:

http://en.wikipedia.org/wiki/GNU_Core_Utilities (section "Text utilities")

http://directory.fsf.org/wiki/Textutils

Run "$ info coreutils"

susi22··on Command-line tools for data science
http://www.hdfgroup.org/HDF5/doc/RM/Tools.html

http://www.hdfgroup.org/tools5desc.html#1

The first thing I do when I deal with data which has more than --let's say-- 10,000 rows is to put it in HDF file format and work with that. Saves a ton of time while developing a script. I had a python script do a histogram and it ran ~15sec for a file with 100k rows. With converting it first to HDF it ran in ~0.5sec. The import in python is also much shorter (two lines).

HDF is made for high performance numerical I/O. It's great and you can query several structures and even do slices of arrays on the command line (with h5tools).

It's also widely used by Octave, Python, R, Matlab... And you don't have a drawback since you can just pipe it into existing command line tools with a h5dump.

HDF5:

http://www.hdfgroup.org/HDF5/RD100-2002/HDF5_Performance.pdf

http://www.hdfgroup.org/HDF5/RD100-2002/HDF5_Overview.pdf

susi22··on Cutcsv: Unix cut for CSV files
3 Things:

- It uses Ruby... Linux command line people don't like ruby dependency. Perl,awk,sed & Python are the "allowed" ones for sysadmin/devops

- It violates the linux command line spirit "Do one thing, and do it well" (it does two)

- I much prefer this: https://github.com/dbro/csvquote

susi22··on My Most Interesting Interview Problem
Yes, that's what the second link is for to normalize it. Maybe I should've made that clearer.
susi22··on My Most Interesting Interview Problem
Q for the math guys:

Is this the closed form pdf of the angle distribution of one quarter of the circle?

http://www.wolframalpha.com/input/?i=1%2Fcos%28min%28x%2Cpi%...

1/cos(min(x,pi/2-x))

plus the normalization term to make \int(..) == 1:

http://www.wolframalpha.com/input/?i=int+1%2Fcos(min(x%2Cpi%...

Constructed by arguing that the probability is directly proportional to the length of the hypotenuse.

susi22··on The Go Oracle: a source code comprehension tool for Go programs
It does have VIM/EMACS integration:

https://code.google.com/p/go/source/browse/cmd/oracle/oracle...

https://code.google.com/p/go/source/browse/cmd/oracle/oracle...

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