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Comment: Re:cool idea, but poorly done (Score 1) 32 32

Agreed. As a climber (haven't done El Cap yet, but have done some long Valley climbs), this is pretty lame. The distance between the images is way too far. I want a real, seamless view that I can follow up a route and see all the details. I want to be able to look at the rock, turn the camera and see all around. Look up, look down, find the next hold, see where my feet would be. You know, all the stuff that makes climbing fun.

Trip reports on Supertopo (www.supertopo.com) are way better than this if you want to get a feel for what it's like to climb a long route.

-Chris

Comment: Re:C++ is never the right tool (Score 4, Interesting) 296 296

Python is written in C. Linux is written in C. OS X is written in C (with libraries in Objective C). Most low level software is written in C, not C++. It's very important for this exercise to differentiate C from C++. They are not the same language and haven't been since C++ stopped being implemented using macros and the preprocessor and got its first compiler.

C is a much simpler language to learn and maintain, especially if you're doing low level code. C++ has a lot of very nice features, but it's benefits really only come into play if you're willing to put the time and effort into properly learning generic programming (the foundation Boost and the STL).

But, as most people have already pointed out, starting with Python and then migrating portions over to C or C++ as needed for performance is a much better approach. You can manage IO just as effectively from Python as you can from C or C++ and your development time will be much much shorter.

-Chris

Comment: Re:The Fuck? (Score 4, Insightful) 175 175

And the author hasn't looked at a relation database in the last few years, either. PostgreSQL, Oracle, MySQL, and I'm sure the other big ones all have JSON (or similar) column types now that let you attach semi-structured elements to your records. You get all the benefits of a RDBMs (ACID, referential integrity, 40 years of history) _and_ all the benefits of NoSQL.

Seriously, there's no good reason not to start with PostgreSQL and only add MongoDB if you really have a good use case for it (you know, you suddenly need to be Web Scale). Personally (and professionally), I use both, with PostgreSQL as the main DB for everything and MongoDB for read-only collections of indexed data.

My challenge to devs out there: spend the hour it takes to learn SQL and understand what you can actually do with it. And, stop pretending that an RDBMS won't scale to meet your needs (spoiler alert: it will).

-Chris

Comment: Re:Learn from the wealthiest (Score 2) 150 150

Huh? Can you back that up with some evidence? I'm not in the super wealthy class, but do know some of them. They all let their kids use smartphones and tablets. Just as I let my kids use them and so do all my friends. Sure, there are the occasional families that don't allow access or restrict access, but those are few and far between - much like the families without TVs when I was growing up in the 80s.

Comment: It's OK to Quit (Score 2) 583 583

Your first job could be the best job you'll ever have and it could be your last job. But, it could also be the worst job you'll have.

Be honest with yourself. If it's not working, don't be afraid to move on. It's not worth being miserable when you're just starting your career. Don't quit impulsively, but if things don't feel right, ask some older friends if what you're experiencing is normal or not. You don't have the experience yet to know better, but your elders do.

My first job was as a software engineer at a site everyone over 30 has used (it's still around, but not as popular). It was the early days of the internet. At my 6 month review, I got "dinged" for going home one morning at 3 am when everyone else stayed through the night. This was after two weeks of 18 hour days. I was doing more harm than good coding at that point. I was being paid $33k/yr and had no stock options. I was told everyone had to do this to keep up with "Internet Time". Over the next few weeks, most of the senior developers (back when senior developers were actually senior with 10+ years' experience) quit en masse. It took me a few more months to realize that this was not normal and leave as well. I would have been much better off walking after the first month.

-Chris

Comment: Re:Pay them market value (Score 5, Insightful) 234 234

Most CS professors are paid market value. You can look up salaries at public schools. You'll find that at the ones that compete with CMU, the salaries are all in the range of what the researchers would make at a company ($100-250k). Bonuses are a little harder to compete with. But, in CS at least, grants cover a ton of travel. To publish in CS, you have to go to the conferences you're publishing in, unlike the rest of science which just has journals. That more than makes up for the lack of bonuses as far as fringe benefits go.

Now, the one benefit you get from industry is that you don't have to write grants. But, you also have more job security in academia. What worries me most about this is that when this bubble bursts, Uber will be one of the first companies to go (at least, research at Uber will go quickly). These researchers will now be stuck without jobs in a market that will be very hostile towards PhDs. For their sake, I hope they all vest quickly enough to get a nest egg before things go south. (it's going to happen, it always does)

-Chris

Comment: I had microwave Internet 15 years ago... (Score 3, Informative) 221 221

In Lousiville, CO, I lived in one of the few neighborhoods that was skipped over for broadband in 1999. Sprint setup a microwave service that filled in the gap. Bandwidth was awesome - I was getting 10-30 MBs regularly. The downside was the latency - 100 ms ping times were the norm. I remember trying to play Duke Nuke 'Em with friends and having the unfair "advantage" of disappearing regularly when my client didn't ping back in time. Being line-of-site, there were also issues with trees occasionally swaying in front of the dish (a pizza box attached to my roof) and snow blocking the signal.

As others have pointed out, microwave Internet isn't something new and, unfortunately, in the real world isn't a perfect solution.

-Chris

Comment: Hadoop was never really the right solution... (Score 5, Insightful) 100 100

A scripting language with a good math/stats library (e.g., NumPy/Pandas) and decent raid controller are all most people really need for most "big data" applications. If you need to scale a bit, add few nodes (and put some RAM in them) and a job scheduler into the mix and learn some basic data decomposition methods. Most big data analyses are embarrassingly parallel. If you really need 100+ TB of disk, setup Lustre or GPFS. Invest in some DDN storage (it's cheaper and faster than the HDFS system you'll build for Hadoop).

Here's the break down of that claim in more computer sciencey terms: Almost all big data problems are simple counting problems with some stats thrown in. For more advanced clustering tasks, most math libraries have everything you need. Most "big data" sizes are under a few TB of data. Most big data problems are also I/O bound. Single nodes are actually pretty powerful and fast these days. 24 cores, 128 GB RAM, 15 TB of disk behind a RAID controller that can give you 400 MB/s data rates will cost you just barely 5 figures. This single node will outperform a standard 8 node Hadoop cluster. Why? Because the local, high density disks that HDFS encourages are slow as molasses (30 MB/s). And...

Hadoop has a huge abstraction penalty for each record access. If you're doing minimal computation for each record, the cost of delivering the record dominates your runtime. In Hadoop, the cost is fairly high. If you're using a scripting language and reading right off the file system, your cost for each record is low. I've found Hadoop record access times to be about 20x slower than Python line read times from a text file, using the _same_ file system for Hadoop and Python (of course, Hadoop puts HDFS on top of it). In Big-O terms, the 'c' we usually leave out actually matters here - O(1*n) vs. O(20*n). 1 hour or 20 hours, you pick.

If you're really doing big data stuff, it helps to understand how data moves through your algorithms and architect things accordingly. Almost always, a few minutes of big-O thinking and some basic knowledge of your hardware will give you an approach that doesn't require Hadoop.

tl;dr: Hadoop and Spark give people the illusion that their problems are bigger than they actually are. Simply understanding your data flow and algorithms can save you the hassle of using either.

-Chris

Comment: Re:Old browsers (Score 2) 276 276

Two years is our horizon for browser support. Two other trends that have helped us in this regard are (1) that most browsers auto-update or at least nag you a lot and (2) IT departments are more accepting of users running Chrome/Safari/Firefox alongside IE. We're targeting enterprise/internal users, not everyone on the Web, so we can also put some requirements in place when we deploy.

Most of our functionality uses standard HTML/CSS/DOM features, so our we haven't had any issues with features dropping. We don't rely on 3rd party extensions such as Flash or APIs/features that don't have broad support. The decision to use Canvas over SVG for complex visualizations is due to partly this - SVG support is spotty across browsers, Canvas is pretty stable now. Canvas is also much faster at rendering large data sets, which is the other reason for using it.

-Chris

Comment: Why we targeted the browser... (Score 5, Interesting) 276 276

I run a company that develops a laboratory informatics platform for data intensive science applications that mix wet lab and analytics operations into single workflows, with gene sequencing as the motivating application - think LIMS with a pipeline and visualization engine, if you're familiar with the space. (Lab7 Systems, if you're curious - http://www.lab7.io/

When we started development a few years ago, we had to make the decision as to whether or not to build a desktop application or a browser-based application. At the time, this wasn't an easy decision. Some aspects of the UI are straightforward form-style interfaces, but others are graphics heavy visualizations of very large data sets (100+ GB in some cases). Scientific and information visualization have almost always benefitted from local graphics contexts and native rendering engines. In addition, the data decomposition tasks often require efficient implementations in compiled languages. Our platform also controls analysis processes on large clusters, another task not well suited for the browser.

We gambled a bit and decided that the browser would be our primary user interface. Two trends at the time helped us make the decision (and luckily they both held steady):

  (1) The JavaScript engines in all the major browsers get faster with each new release and now outperform other scripting languages for many tasks.
  (2) The JavaScript development community is maturing, with more well-engineered and stable libraries available

As few other considerations helped us make the call:

  (1) Our platform is a multi-user system. A desktop client would add to the support burden for our customers.
  (2) Our backend needs to integrate with compute clusters, scientific instruments, and large, high-performance file systems. It is server-based, regardless of the client.
  (3) The data scales we were dealing with also required "out-of-core" (to use an older term) algorithms for redenering, so the client would never get entire data sets at once.
  (4) REST/json... XML, XMLRPC, SOAP, and all the others are a pain to develop for (I speak from experience), REST/json significantly reduced the amount of code we needed to maintain state between the client and server.

Since we made the call to use the browser, we haven't looked back. Early on there were some user interactions that were tricky to implement across all browsers, but today they've all caught up. Our application looks much more like a desktop or (*shudder*) Flash application, with a very rich UI (designed by an actual UX team that gets scientific software ;) ) and complex visualizations. It's also been relatively straight-forward to implement, thanks in large part to the maturity of some JavaScript libraries (we use jQuery, D3 (for complex filtering, but not for visualization), Canvas, Backbone, and a few others).

Personally, I can't imagine ever writing a desktop application again. The browser is just too convenient and, in the last few years, finally powerful enough for most tasks.

-Chris

Comment: Re:Investments? (Score 1, Insightful) 202 202

$20M on salaries sounds about right for an organization with a complex IT infrastructure and global reach. Not sure what the outrage is here, unless you're expecting the people that keep the site up to work for free.

If they were developing the content as well, I'd expect their salaries to be in the $30-50M range. $1M probably gives you 6-8 editorial FTEs, so $30-50M would give you the few hundred editors and their support staff necessary to produce the content. The numbers are different for IT staff - 4-5 FTEs/$1M, so $20M could cover 80 technical staff and a few managers. Of course, there's all other staff as well, so the technical staff numbers are probably lower.

Other posts have already pointed out that $50M in the bank is a smart move for a non-profit.

-Chris

Comment: Re:HIPAA violation (Score 1) 101 101

But the FDA did smack down 23andMe pretty hard for making medical claims based on SNP profiling.* While HIPPA isn't the right regulatory regime here, the FDA definitely is. 23andMe tried the Uber approach to flaunting regulations and found that when actual human health is involved, "trust us" doesn't cut it.

-Chris

*Can we please stop calling what these companies are doing "DNA sequencing"? It's not and never has been. It's just looking for specific, known markers in your genome. Sequencing is actually getting a readout of your genome.

The rule on staying alive as a forecaster is to give 'em a number or give 'em a date, but never give 'em both at once. -- Jane Bryant Quinn

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