Mexican Blanket (#127)

bbazzarrakk · June 8, 2007, 2:48pm

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-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

by Scott Prager

I’m looking at this blanket my dad got in Mexico, and I’m noticing that
it has
an interesting gradient. There are two colors (c1 and c2) and the
outside c1 is
5 stitches wide, then a 1 stitch c2, 4 stitches c1, 2 stitches c2… It
looks
something like this:

RRRRRBRRRRBBRRRBBBRRBBBBRBBB
RRRRBRRRRBBRRRBBBRRBBBBRBBBB
RRRBRRRRBBRRRBBBRRBBBBRBBBBB
RRBRRRRBBRRRBBBRRBBBBRBBBBBY
RBRRRRBBRRRBBBRRBBBBRBBBBBYB
BRRRRBBRRRBBBRRBBBBRBBBBBYBB
RRRRBBRRRBBBRRBBBBRBBBBBYBBB
RRRBBRRRBBBRRBBBBRBBBBBYBBBB
RRBBRRRBBBRRBBBBRBBBBBYBBBBY
RBBRRRBBBRRBBBBRBBBBBYBBBBYY
BBRRRBBBRRBBBBRBBBBBYBBBBYYB
BRRRBBBRRBBBBRBBBBBYBBBBYYBB
RRRBBBRRBBBBRBBBBBYBBBBYYBBB
RRBBBRRBBBBRBBBBBYBBBBYYBBBY
RBBBRRBBBBRBBBBBYBBBBYYBBBYY
BBBRRBBBBRBBBBBYBBBBYYBBBYYY
BBRRBBBBRBBBBBYBBBBYYBBBYYYB
BRRBBBBRBBBBBYBBBBYYBBBYYYBB
RRBBBBRBBBBBYBBBBYYBBBYYYBBY
RBBBBRBBBBBYBBBBYYBBBYYYBBYY
BBBBRBBBBBYBBBBYYBBBYYYBBYYY
BBBRBBBBBYBBBBYYBBBYYYBBYYYY
BBRBBBBBYBBBBYYBBBYYYBBYYYYB
BRBBBBBYBBBBYYBBBYYYBBYYYYBY
RBBBBBYBBBBYYBBBYYYBBYYYYBYY
BBBBBYBBBBYYBBBYYYBBYYYYBYYY
BBBBYBBBBYYBBBYYYBBYYYYBYYYY
BBBYBBBBYYBBBYYYBBYYYYBYYYYY

It goes on and on like that and when one color ends, another begins.
When two
sets of gradients meet, there is a thick separator. Two gradients don’t
always
meet at the same color, but their opposite borders are usually the same.
(ex:
black-to-yellow |separator| white-to-black) There is also the occasional
gradient of thick bars of equal length; ex: |green|-|yellow|-|red|. It
looks
like this:

http://www1.istockphoto.com/file_thumbview_approve/2544046/2/

So the challenge is to make a pattern generator to generate the patterns
as seen
in the ASCI and picture. It should, or rather NEEDS to, contain the
Mexican flag
as it is respectful to the culture where this challenge comes from. For
extra
credit, try to put them on a blanket of 200x100 pexels. And if you
really need
extra credit to graduate, make the patterns symmetrical, however make
the colors
in the patterns NOT symmetrical (ex: WWRW middle OBOO).

bbazzarrakk · June 8, 2007, 6:53pm

On Fri, 8 Jun 2007 21:46:56 +0900, Ruby Q. [email protected]
wrote:

It should, or rather NEEDS to, contain the Mexican flag as it is respectful to
the culture where this challenge comes from.

By this, you mean the colors of the Mexican flag? The Mexican flag
proper also includes a rather complex coat of arms in the center, which
seems a little ambitious…

-mental

bbazzarrakk · June 8, 2007, 6:57pm

On Jun 8, 2007, at 11:52 AM, MenTaLguY wrote:

On Fri, 8 Jun 2007 21:46:56 +0900, Ruby Q.
[email protected] wrote:

It should, or rather NEEDS to, contain the Mexican flag as it is
respectful to
the culture where this challenge comes from.

By this, you mean the colors of the Mexican flag? The Mexican flag
proper also includes a rather complex coat of arms in the center,
which seems a little ambitious…

Yes. I’m pretty sure the author was referring to the colors.

James Edward G. II

bbazzarrakk · June 8, 2007, 7:19pm

James G. wrote:

On Jun 8, 2007, at 11:52 AM, MenTaLguY wrote:

On Fri, 8 Jun 2007 21:46:56 +0900, Ruby Q.
[email protected] wrote:

It should, or rather NEEDS to, contain the Mexican flag as it is
respectful to
the culture where this challenge comes from.

By this, you mean the colors of the Mexican flag? The Mexican flag
proper also includes a rather complex coat of arms in the center,
which seems a little ambitious…

Yes. I’m pretty sure the author was referring to the colors.

James Edward G. II

Oh, thank God! Now I might actually attempt this one…

bbazzarrakk · June 9, 2007, 3:13pm

On 6/8/07, Ruby Q. [email protected] wrote:

So the challenge is to make a pattern generator to generate the patterns as seen
in the ASCI and picture. It should, or rather NEEDS to, contain the Mexican flag
as it is respectful to the culture where this challenge comes from. For extra
credit, try to put them on a blanket of 200x100 pexels. And if you really need
extra credit to graduate, make the patterns symmetrical, however make the colors
in the patterns NOT symmetrical (ex: WWRW middle OBOO).

I didn’t quite understand this part.
Is this suitable output for 35x70 ?

GGGGGWGGGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRR
GGGGWGGGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRB
GGGWGGGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBB
GGWGGGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBB
GWGGGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBB
WGGGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBR
GGGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRB
GGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBB
GGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBB
GWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBB
WWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBB
WGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBY
GGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYB
GGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBB
GWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBB
WWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBB
WWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBY
WGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYY
GGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYB
GWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBB
WWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBB
WWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBY
WWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYY
WGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYY
GWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYB
WWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBB
WWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBY
WWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYY
WWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYY
WRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYYY
RWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYYYB
WWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYYYBY
WWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYYYBYY
WWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYYYBYYY
WRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYYYBYYYY

I did not want to post 200 lines here but I made a similar (sloppy and
temporary) HTML file of 200x100 in an attempt to make it easier to
understand the color patterns. Is this an acceptable pattern?
http://www.kakueki.com/ruby/q127.html

Or do I need to add some separators and if so, where? I did not get that
part.

Harry

A Look into Japanese Ruby List in English
http://www.kakueki.com/

bbazzarrakk · June 9, 2007, 6:15pm

On Jun 9, 2007, at 8:12 AM, Harry K. wrote:

gradient of thick bars of equal length; ex: |green|-|yellow|-|
from. For extra
GGGGGWGGGGWWGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRR
WGGGWWWGGWWWWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBY
WWGWWWWWRWWWWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYY
WWRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYYYBYYY
WRRWWWRRRWWRRRRWRRRRRBRRRRBBRRRBBBRRBBBBRBBBBBYBBBBYYBBBYYYBBYYYYBYYYY

I did not want to post 200 lines here but I made a similar (sloppy and
temporary) HTML file of 200x100 in an attempt to make it easier to
understand the color patterns. Is this an acceptable pattern?
http://www.kakueki.com/ruby/q127.html

They both look fine to me. Nice work.

James Edward G. II

bbazzarrakk · June 10, 2007, 4:29pm

My solution builds a color string long enough to run across the top of
the
blanket, turn, and run down the right side. This is shifted left for
every
row. You can visualize the blanket as being a rectangular window on the
parallelogram that is created, like this for 10x5:

[--------]
xxxxxxxxxxxxxx

xxxxxxxxxxxxxx
xxxxxxxxxxxxxx
xxxxxxxxxxxxxx
xxxxxxxxxxxxxx
[--------]

Building the edge string is done mainly by my Blanket.edge method, which
repeatedly chooses a random color to gradient with the previous color.
Blanket.symmetrical_edge can create pattern-and-color symmetrical edges
by creating a half-length edge and flipping it, or pattern-but-not-color
symmetrical edges by doing this and mapping the colors to random colors.

I was able to re-use some of my code from Quiz 125 (fractals) to create
images with RMagick.

Examples:

$ ./mexican_blanket.rb 60 15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$ # Blanket displayed on screen:
$ ./mexican_blanket.rb 300 400 --format display

$ ./mexican_blanket.rb 20 5 --symmetric
GGGGGGGGOGGGYYYRYYYY
GGGGGGGOGGGYYYRYYYYY
GGGGGGOGGGYYYRYYYYYY
GGGGGOGGGYYYRYYYYYYY
GGGGOGGGYYYRYYYYYYYY

$ ./mexican_blanket.rb 20 5 --color-symmetric
OOOOOROOOORRRROOOORO
OOOOROOOORRRROOOOROO
OOOROOOORRRROOOOROOO
OOROOOORRRROOOOROOOO
OROOOORRRROOOOROOOOO

$ ./mexican_blanket.rb 400 600 --format png
Wrote blanket to blanket_400x600.png

An example of that last one can be seen here:
http://www.jessemerriman.com/images/ruby_quiz/127_mexican_blanket/blanket_400x600.png

The full usage statement is at the top of mexican_blanket.rb

If you want to change the colors or stripe widths, its hard-coded at the
top
of the Blanket class, and for graphics at the top of BlanketDraw.

bbazzarrakk · June 10, 2007, 4:33pm

On 6/8/07, Ruby Q. [email protected] wrote:

So the challenge is to make a pattern generator to generate the patterns as seen
in the ASCI and picture. It should, or rather NEEDS to, contain the Mexican flag

My HTML version prints a blanket in color.

It is quick and dirty HTML that could certainly

be improved but it is viewable.

This makes a 200x100 blanket.

It looks like this http://www.kakueki.com/ruby/q127.html

Code Start

outs = File.new(“./q127.html”,“w”)
colors = “GWRBYRGRRGRYBRWG”
ahash = {}
ahash.store(“G”,“”+“o” + “”)
ahash.store(“W”,“”+“o” + “”)
ahash.store(“R”,“”+“o” + “”)
ahash.store(“B”,“”+“o” + “”)
ahash.store(“Y”,“”+“o” + “”)

unp = “aXaXaXaXaa”
(1…colors.length).each do
(1…4).each {|y| unp<<“X”<<“Xa”*(5-y)<<“a”<<“Xa”*y}
unp << “a”
end
row = colors.unpack(unp)
row.map! {|x| ahash[x] }
outs.puts “<body bgcolor="#dddddd">”

200.times do
outs.print row[0…99].join
outs.print “
\n”
row.shift
end

outs.puts “”
outs.close

Harry

–

A Look into Japanese Ruby List in English
http://www.kakueki.com/

bbazzarrakk · June 10, 2007, 6:47pm

I have been meaning to have a closer look at RMagick for a while, so
This quiz
seemed a good opportunity to do so.The actual pattern generator came
together
surprisingly quickly, and it was a breeze to draw with RMagick, so I
spent
most of my time working on the ‘random bits’ to give the blankets a bit
of
personality.

My script is fairly simple, it takes as argument first, Xpx and Ypx, and
then
any number of colours. If you want to use only a few colours but still
have
some changes you can specify them multiple times, ie: “yellow red green
yellow red green yellow red green” etc. Otherwise the pattern is just
extended the width of the image.

I posted a couple finished blankets on my site:
$ mexican_blanket.rb 200 400 green yellow red
created: http://badcomputer.org/images/blanket1.png (7K)

$ mexican_blanket.rb 400 800 400 800 blue green yellow white red orange
brown
green yellow blue
created: http://badcomputer.org/images/blanket2.png (25K)

And the code:

#!/usr/bin/ruby

mexican_blanket.rb - Draw a png image which resembles

a traditional mexican blanket

Usage:

$ mexican_blanket.rb width height colour [colour]…

width and height are integers

colours may be specified by name eg: ‘yellow’

or by hex code eg: ‘#FFFF00’

require ‘RMagick’

COLUMNS = ARGV[0].to_i # First arg is blanket width in px
ROWS = ARGV[1].to_i # Second arg is blanket height in px
colours = ARGV[2…-1] # Remaining args are colours

def mexican_blanket_magic(colours)
ptr = -1
pattern = []
colours.size.times do
# Next 10 lines build the gradient
5.times { pattern[ptr += 1] = colours[0] }
pattern[ptr+=1] = colours[1]

4.times { pattern[ptr+=1] = colours[0] }
2.times { pattern[ptr+=1] = colours[1] }

3.times { pattern[ptr+=1] = colours[0] }
3.times { pattern[ptr+=1] = colours[1] }

2.times { pattern[ptr+=1] = colours[0] }
4.times { pattern[ptr+=1] = colours[1] }

pattern[ptr+=1] = colours[0]
5.times { pattern[ptr+=1] = colours[1] }

# This is our black stripe which divides the gradients
n = rand(100)
if n <= 20    # Aprox. 20% chance of 3px wide line
  3.times { pattern[ptr+=1] = "black" }
elsif n >= 80 # Aprox. 20% chance of 7px wide line
  7.times { pattern[ptr+=1] = "black" }
end           # Aprox. 60% chance of no line

# Aprox. 20% chance we will get a diagonal bar
# of random colour and size (<= 21px)
if rand(100) < 20
  clr = colours[rand(colours.size)]
  (rand(20)+1).times { pattern[ptr+=1] = clr }
end

# Rotate through the colours in order
cs = colours.shift
colours.push(cs)

end

Pad out the pattern to match image width

ptr = -1
while pattern.size < COLUMNS
pattern << pattern[ptr+=1]
end
return pattern
end

Create our pattern

pattern = mexican_blanket_magic(colours)

Create the image canvas

blanket = Magick::Image.new(COLUMNS, ROWS)
stitch = Magick::Draw.new

This is the plotter. Basically we just

stamp out a row, left-shift the pattern

and continue till all the rows are done.

yptr = 0
ROWS.times do
xptr = 0
COLUMNS.times do
stitch.fill(pattern[xptr]) # Set colour
stitch.point(xptr, yptr) # Plot point
xptr += 1
end
cc = pattern.shift
pattern.push(cc)
yptr += 1
end

Write the drawing to the canvas,

and the canvas to a file.

stitch.draw(blanket)
blanket.write(“blanket.png”)

end mexican_blanket.rb

BTW, sorry for all the ‘ptr’ damage, been writing a lot of C lately…

-d

bbazzarrakk · June 10, 2007, 3:01pm

On 6/8/07, Ruby Q. [email protected] wrote:

So the challenge is to make a pattern generator to generate the patterns as seen
in the ASCI and picture.

Here is my solution.

I built a string to use for unpacking.

Then I used the string to unpack.

It should work for a blanket of any size if the

‘colors’ string is long enough.

Code Start

colors = “GWRBYRGRRGRYBRWG”
unp = “aXaXaXaXaa”
(1…colors.length).each do
(1…4).each {|y| unp<<“X”<<“Xa”*(5-y)<<“a”<<“Xa”*y}
unp << “a”
end
row = colors.unpack(unp)
35.times do
puts row[0…69].join
row.shift
end

Harry

–

A Look into Japanese Ruby List in English
http://www.kakueki.com/

bbazzarrakk · June 10, 2007, 7:25pm

Andreas L. wrote:

Cycle the colors if we need more. The relationship between

supersequence length l, interval_length w, and number of colors c is

l = (1 + (c-1) * w) * w <=> c = ceil((l - w) / w^2) + 1

And yes, that’s wrong. There shouldn’t be an equivalence there.

bbazzarrakk · June 10, 2007, 6:53pm

Ruby Q. wrote:

So the challenge is to make a pattern generator to generate the patterns as seen
in the ASCI and picture.

Idea: Each line constains a repeating pattern, and the lines themselves
are also repeating patterns. Therefore compute the supersequence of the
lines, then extract subsequences from that to retrieve the complete
pattern.

INTERVAL_LENGTH = 5 # The interval at which the color-pattern changes.
LINE_LENGTH = 100
ROW_COUNT = 200

Mexican flag.

colors = %w{G W R}

Cycle the colors if we need more. The relationship between

supersequence length l, interval_length w, and number of colors c is

l = (1 + (c-1) * w) * w <=> c = ceil((l - w) / w^2) + 1

length_needed = ROW_COUNT + LINE_LENGTH - 1
colors_needed = ((length_needed - INTERVAL_LENGTH).to_f /
INTERVAL_LENGTH**2).ceil + 1
colors *= (colors_needed.to_f / colors.size).ceil

Create a supersequence for the lines. Reverse the colors and slice

from the end of the pattern to get the correct order.

color_pattern = colors.reverse.map{ |c| c * INTERVAL_LENGTH }.join
line_superseq = ‘’
INTERVAL_LENGTH.upto(color_pattern.size) do |i|
line_superseq << color_pattern.slice(-i, INTERVAL_LENGTH)
end

Sample the line-sequence a few times to produce the complete pattern.

ROW_COUNT.times do |i|
puts line_superseq[i, LINE_LENGTH]
end

I didn’t really understand what kind of symmetry was requested, but
replacing the colors with the following can be used to create the
pattern posted by Harry, the need for repetition of colors probably
means I misunderstod something though.

Recreates the pattern posted by Harry.

colors = %w{G W R B Y R G R}
colors += colors.reverse

bbazzarrakk · June 10, 2007, 8:21pm

On Sunday 10 June 2007 12:38, Tim H. wrote:

Again, very cool!

Tim

Right you are Tim. Attached is my new blanket_image.rb improved in the
way
you suggested (blanket_draw.rb can be discarded now). Quite a
difference:

$ time ./mexican_blanket.orig.rb 800 800 --format png
Wrote blanket to blanket_800x800.png

real 0m28.706s
user 0m25.757s
sys 0m0.454s

$ time ./mexican_blanket.rb 800 800 --format png
Wrote blanket to blanket_800x800.png

real 0m7.687s
user 0m7.452s
sys 0m0.070s

(BTW, your message appears to have been sent to just me, not the list.
Not
sure if this was intentional. If so, hope you don’t mind me moving to
the
list.)

bbazzarrakk · June 10, 2007, 10:01pm

On Jun 8, 7:46 am, Ruby Q. [email protected] wrote:

The three rules of Ruby Q.:

Here is my solution. It’s rather long, but provides enough flexibility
to
reuse the code, add more colors, etc.
Displays in Unix terminals and PPM Images

http://pastie.caboo.se/69309

It should, or rather NEEDS to, contain the Mexican flag
as it is respectful to the culture where this challenge comes from.

As a mexican, I shall say the don’t need the Mexican Flag colors, as
their origin comes from prehispanic times, way before those colors
appeared as a national symbol. Nevertheless, they are often included
nowadays.

Thanks for the quizes.

Ruben M…

bbazzarrakk · June 10, 2007, 11:54pm

I’m very much a newb, but I figure that the best way to learn Ruby
isn’t sitting on the sidelines. So here’s my solution (hacked, but it
works):

==== mexican_blanket.rb ====
class MexicanBlanket
def initialize(colors, length, max_width)
colors = colors
@length = length
max_width = max_width

@current_row = 0

generate ‘complete’ line

@complete_pattern = generate_complete_pattern(colors,max_width)
end

def first_row
@complete_pattern[0…@length].to_s
end

def next_row
length = @length + @current_row
row = @complete_pattern[@current_row … length]
@current_row += 1
row.to_s
end

def generate_complete_pattern(colors, max_width)
first_two = mix_two_colors(colors[0…1],max_width)
last_two = mix_two_colors(colors[1…2],max_width)
last_two.shift;
complete_pattern = first_two
complete_pattern << last_two
return complete_pattern.to_s.split(//)
end

def mix_two_colors(colors,max_width)
first_color = colors[0]
second_color = colors[1]
first_width = max_width
second_width = 1
two_colors = []
until (second_width > max_width)
two_colors << first_color * first_width << second_color *
second_width
first_width -= 1
second_width += 1
end
return two_colors
end

attr_reader :complete_pattern # for testing
end
==== end mexican_blanket.rb ====

==== print_mexican_flag_blanket.rb ====
#!/usr/bin/env ruby -wKU

require “…/lib/mexican_blanket”

colors = [“G”,“W”,“R”]
line_length = 28
color_max_width = 5
rows = 28

mexican_flag_blanket =
MexicanBlanket.new(colors,line_length,color_max_width)

rows.times { |n| puts mexican_flag_blanket.next_row }
==== end print_mexican_flag_blanket.rb ====

bbazzarrakk · June 12, 2007, 6:40pm

My solution…, I’ve spent an extra 10 minutes to put the code into a
class.

http://pastie.caboo.se/69806

#! /usr/bin/ruby

usage: $> ruby quiz#127.rb <color_width>

without args it prints carpet of 100*200 with color_width 5.

class MexicanCarpet
COLORS = %w(W Y G W B)

def initialize(width, rows, color_width)
@width, @rows, @color_width = width, rows, color_width
total_width = @width * @rows

 @color_stack = ""

 # make one long line of colors
 (COLORS.length-1).times do |i|
   color1 = COLORS[i]
   color2 = COLORS[i+1]

   color_width.times do |i|
     @color_stack << color1 * (@color_width-i)
     @color_stack << color2 * (i + 1) if i < @color_width - 1
   end
 end

 while total_width > @color_stack.length do
   @color_stack_ = @color_stack_ ? @color_stack_.reverse :

@color_stack[5…-1].reverse
@color_stack += (@color_stack[-2…-2] * @color_width) +
@color_stack_
end

 @color_stack << COLORS.last * @color_width
 print_carpet

end

def print_carpet
# print slices of the color_stack
@rows.times do |row|
puts @color_stack[row…row+@width]
end
end

end

width = ARGV[0] ? ARGV[0].to_i : 100
rows = ARGV[1] ? ARGV[1].to_i : 200
color_width = ARGV[2] ? ARGV[2].to_i : 5

MexicanCarpet.new( width, rows, color_width )