Another Demo movie of "Muroto for iPad"

Hi, it is NISHIO Hirokazu. I posted Hacker's Cafe Blog: MUROTO: tangible figure as a controller for iPad apps, however it said difficult to see that Muroto can get the information of position and direction. So I made another demo program and movie again!

In the movie, it is more clear:

MUROTO: tangible figure as a controller for iPad apps

Hi, it is NISHIO Hirokazu. I and KUCHII Jun made a system to control iPhone/iPad apps with tangible figure for "Make: Tokyo Meeting 05" on the last Sunday. We called it "MUROTO". Using MUROTO you can know the type of figure you put on iPhone, the direction and also position(not shown in movie)
So you can use tangible figures as a controller! We are making demo apps for iPad now. Don't miss it! See also: PONG-like game played on iPad with tangible controller

13 chars in [4,+,-,*,/] can make all number in range(60)

Hi, it is Dr. NISHIO Hirokazu. Today I wonder how much characters required to make fixed-width one-digit-only digital clock. Which digit is the most suitable?

When I allow to use bitwise calculation, 5 is the most suitable digit. It requires only 8 characters.

0       555/5555
1       ~~-5+-~5
2       -~-5+-~5
3       555&5*55
...

Surprisingly in the hardest restriction it requires only 13 characters.

• no bitwise operation. allow only the 4 arithmetical operations.
  
• no minus-minus connection. 4--4 = 4 - -4 is not allowed
  
• negate operation should not be aside of the other operation. 4+-4, 4*-4, 4/-4 are also omitted
  
• true division. 4 / 44 is not 0, it is 1 / 11.
  

Here is the result. I think 37 == 4444/44-4*4*4 is very cute!! I love it!

0 4444*4-4*4444
1 44-44+444/444
2 4/4+4444/4444
3 44/44+4/4+4/4
4 4-4/4+444/444
5 4-4-4+4+4+4/4
6 4-4/4+4-44/44
7 -4-44+44+44/4
8 4-4*44+44*4+4
9 4-4+4+4+44/44
10 444/4-4444/44
11 -4+4-4+4+44/4
12 4-4-4-4+4*4+4
13 4-4-4+4*4+4/4
14 4-4/44+444/44
15 4-4+4*4-44/44
16 -4-4-4-4*4+44
17 4*4+4444/4444
18 4+4*4-4/4-4/4
19 -44+4*4*4-4/4
20 4-4/4+4*4+4/4
21 4-4+4+4*4+4/4
22 4-4+44/4+44/4
23 4+4+4*4-44/44
24 4-44+44+4*4+4
25 -4-4*4+44+4/4
26 -4/4+4*4+44/4
27 -4+4*4+4+44/4
28 4*4-4-4+4*4+4
29 4-4-4-44/4+44
30 4+4+44/4+44/4
31 4*4+4*4-44/44
32 44-44/4-44/44
33 44/44+4*4+4*4
34 44+44/44-44/4
35 -44/44-4-4+44
36 -44-4-4+44+44
37 4444/44-4*4*4
38 4-44/4+44+4/4
39 -4-4+4-4/4+44
40 -4*4-4+4*4+44
41 -4+44+444/444
42 -4+44+4/4+4/4
43 -4+44+4-44/44
44 -4*44+44*4+44
45 -44+44+44+4/4
46 -4/4-4/4+4+44
47 -4-4/4+4+44+4
48 -4-4-4+4*4+44
49 -44/4-4+4*4*4
50 44-4-4/4+44/4
51 4+44+44/4-4-4
52 -44+4+44+44+4
53 44+4+4*4-44/4
54 44+44/4-44/44
55 44-44+44+44/4
56 4-4-4-4+4*4*4
57 4/4-4-4+4*4*4
58 4-4/4+44+44/4
59 44+4-4+4+44/4

see also The list of all numbers which can generate from nine 4s and arithmetics operations.

What happen if you put both str and unicode key on a dict in Python?

In [1]: {u"a": 1, "a": 2}
Out[1]: {u'a': 2}

Yas, it is because:

In [2]: u"a" == "a"
Out[2]: True

Python2.* think u"a" and "a" are EQUAL. of course:

In [3]: u"a" is "a"
Out[3]: False

they are not IDENTITY. If Guido designed to use IDENTITY to check whether they are SAME key, it causes:

In [4]: (1, 2) is (1, 2)
Out[4]: False

that uncomfortable behavior. We don't want to distinguish EQUAL tuples. It is a difficult question on designing new languages. Those behavior was changed from Python3.0. On it, bytes(byte sequence) and text(unicode char sequence) are not compatible. No automatic conversion between them.

>>> b"a" == "a"
False
>>> {b"a": 1, "a": 2}
{b'a': 1, 'a': 2}

A Quiz like an IQ test

Hi, it is Dr. NISHIO Hirokazu. I enjoyed an IQ test by Mensa. And found such a non-verbal quiz is good for publishing to the world. I just made another quiz. Please try it!


It is published under Creative Commons BY 3.0 License.

For your information: my IQ was 138.

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Making quiz is fun! Here is another one!

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And another one!

Can you say what this graphics is?

Hi, it is Dr. NISHIO Hirokazu, a mathematical artist!

Today's question is:


Hint: There are no randomness. There are no magic numbers in my code (except for the paper's width, height and an 2)

Here is a close-up of the graphics:

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I struggled to show the interesting mathematical interesting structures and got this:



It contains some magic numbers (for folding, spacing etc.) but more easy to understand than the first 'pure' graphics.

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P.S. (2010-01-07)

Ivanhoe said

Without a high-resolution version of the complete (or at least the upper left corner) of the artwork it seems hard to guess.

Oh, it is very good question. The upper left corner is the most important part of the artwork. It helps you to solve the quiz.

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Ivanhoe said...

I would say that this figure the last bit or the sum parity of some 2D function, am I close ?

It is reciprocal numbers in binary notation. 1/2 = 0.1, 1/3 = 0.01010101..., 1/4 = 0.01, 1/5 = 0.00110011, etc. I omit preceding 0s, and make 0 as black, 1 as white. Left-most column corresponts to 1/2.

iTheremin will be on Make: Tokyo Meeting 04

Hi, it is NISHIO Hirokazu. I just made a new promotion movie of my iPhone software: iTheremin. You can control iTheremin without touch.


I and other members of Hacker's Cafe will exhibit on Make: Tokyo Meeting 04. Some belongs to Hacker's Cafe group, others Team Lab group and I Tsuden-Mitoh groups. We are too active to be organized in a shape, ;-)

I'll demonstrate the software on Make: Tokyo Meeting 04. Meet me!