Dog vision is way worse than ours!

It seems a dog's vision is way worse than a man!

It is 20/75 instead of 20/20. That is what a normal man see at 75 ft can be seen only by dog at 20ft.


http://www.psychologytoday.com/blog/canine-corner/201009/how-good-is-dog-s-visual-acuity-compared-people

I heard this in this talk:

http://www.youtube.com/watch?v=rconzwB422s&playnext=1&list=PL680E0DEE270EF70E

and wanted to confirm and inded Dog is legally blind!

Blackberry yellow circle indicator!

It is the most stupid icon I have seen!

I searched for the actual reason for this indicator for 15 minutes. Indicators have to be intuitive, But it is not even close.

In the end I found out that it is for WAP push messages by mobile provider [ads basically], which endup in Messages in a separate folder. It can also be browser feeds, BTW.

Print screen in mac

Simple.

Command+Shift+4

Elegant integration of sinx/x from 0 to infinity

I learned two things called Contour integral and Jordan's lemma today.

It helps solve this integral elegantly.

To evaluate this you can use e^iz/z and integrate it over 2 semi circles and 2 line segments and residue theorem to convert this into evaluation of this integral. It is really elegant.
It uses Jordan's lemma along the way to make one of the semi circle integral 0 as its radius R goes to infinity.

Waking Up in the Universe - Growing Up in the Universe - Richard Dawkins

Great lecture! You really feel special and motivated to do something special and useful with your life.
1. Illustration of the power of exponential.
2. How lucky we are to born over other possible sperms and eggs and even over other ancestors.
3. Power of scientific prediction with a heavy ball.
4. Illustration of time scales involved with 500 million etc.
5. Why very eerie occurences are no so special after all, given the number of people.

Genesis of purpose!

Great video from christmas lectures of 1991 by Dr. Richard Dawkins.

I was feeling a bit blue yesterday and tried to find purpose in life [I have long outgrown religions] and hit upon this video. I was totally refreshed by this video. Although I have seen it earlier, every time I see it, I get a different perspective. His style of explanation is excellent.

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Ep5: The Genesis of Purpose - Growing Up

Nice putnam question

Prove that this is not prime for any n.

I found this question in putnam question paper and it has real elegant solution too.
It is too good to not to solve it yourself.