Hi,
I defined and populated a 9x9 matrix (Array of Arrays) of strings, m
I defined an element-extractor:
class Array
def get(i,j)
line =self[i-1]
char = line[j-1]
end
end
To get the first element of the second row, I used the following,
which worked fine:
m.get(2,1)
I'd like to write merely m(2,1). How can I do that simply?
Thanks in Advance,
Richard
Hi,
You do this:
class Array
alias old_
def *args
if *args.length == 2 && args[0].is_a? Integer && args[1].is_a? Integer
get(*args)
else
old_(*args)
end
end
Of course, this would remove some of the functionality of an Array for
every Array, not just matricies. Consider making a subclass of Array
like this:
class Matrix < Array
...
end
Now you can modify Matrix at will without affecting Array.
If you are creating a Matrix for purely pragmatic reasons (i.e., not
as an excercise) then there is an excellent Matrix class in the Ruby
standard library: RDoc Documentation
Dan
On Sat, May 3, 2008 at 4:05 PM, RichardOnRails <RichardDummyMailbox58407@uscomputergurus.com> wrote:
Hi,
I defined and populated a 9x9 matrix (Array of Arrays) of strings, m
I defined an element-extractor:
class Array
def get(i,j)
line =self[i-1]
char = line[j-1]
end
endTo get the first element of the second row, I used the following,
which worked fine:m.get(2,1)
I'd like to write merely m(2,1). How can I do that simply?
Thanks in Advance,
Richard
Hi,
You do this:
class Array
alias old_
def *args
if *args.length == 2 && args[0].is_a? Integer && args[1].is_a? Integer
get(*args)
else
old_(*args)
end
endOf course, this would remove some of the functionality of an Array for
every Array, not just matricies. Consider making a subclass of Array
like this:
class Matrix < Array
...
endNow you can modify Matrix at will without affecting Array.
If you are creating a Matrix for purely pragmatic reasons (i.e., not
as an excercise) then there is an excellent Matrix class in the Ruby
standard library:RDoc DocumentationDan
> Hi,
> I defined and populated a 9x9 matrix (Array of Arrays) of strings, m
> I defined an element-extractor:
> class Array
> def get(i,j)
> line =self[i-1]
> char = line[j-1]
> end
> end> To get the first element of the second row, I used the following,
> which worked fine:> m.get(2,1)
> I'd like to write merely m(2,1). How can I do that simply?
> Thanks in Advance,
> Richard
Hi Daniel,
Thanks for the "kick start" and the Matrix class. I got the latter
working, but I'm going to "roll my own" because I want a Sudoku
solver that works the way I do manually. I know there's a free solver
written in VisualProlog, but like Frank Sinatra, "I'll do it my
way" 
alias old_
I'm running ruby 1.8.6 (2007-09-24 patchlevel 111) [i386-mswin32]. It
barfed on "old_", so I substituted:
else
super(*args)
which worked fine.
Best wishes,
Richard
On May 3, 9:06 pm, Daniel Finnie <d...@danfinnie.com> wrote:
On Sat, May 3, 2008 at 4:05 PM, RichardOnRails > > <RichardDummyMailbox58...@uscomputergurus.com> wrote:
I should have mentioned that I used "alias old_ " in the context
of "Matrix < Array", so there's no wonder it didn't work. Sorry about
that omission.
On May 4, 4:38 pm, RichardOnRails <RichardDummyMailbox58...@uscomputergurus.com> wrote:
On May 3, 9:06 pm, Daniel Finnie <d...@danfinnie.com> wrote:
> Hi,
> You do this:
> class Array
> alias old_
> def *args
> if *args.length == 2 && args[0].is_a? Integer && args[1].is_a? Integer
> get(*args)
> else
> old_(*args)
> end
> end> Of course, this would remove some of the functionality of an Array for
> every Array, not just matricies. Consider making a subclass of Array
> like this:
> class Matrix < Array
> ...
> end> Now you can modify Matrix at will without affecting Array.
> If you are creating a Matrix for purely pragmatic reasons (i.e., not
> as an excercise) then there is an excellent Matrix class in the Ruby
> standard library:RDoc Documentation> Dan
> On Sat, May 3, 2008 at 4:05 PM, RichardOnRails > > > <RichardDummyMailbox58...@uscomputergurus.com> wrote:
> > Hi,> > I defined and populated a 9x9 matrix (Array of Arrays) of strings, m
> > I defined an element-extractor:
> > class Array
> > def get(i,j)
> > line =self[i-1]
> > char = line[j-1]
> > end
> > end> > To get the first element of the second row, I used the following,
> > which worked fine:> > m.get(2,1)
> > I'd like to write merely m(2,1). How can I do that simply?
> > Thanks in Advance,
> > RichardHi Daniel,
Thanks for the "kick start" and the Matrix class. I got the latter
working, but I'm going to "roll my own" because I want a Sudoku
solver that works the way I do manually. I know there's a free solver
written in VisualProlog, but like Frank Sinatra, "I'll do it my
way"> alias old_
I'm running ruby 1.8.6 (2007-09-24 patchlevel 111) [i386-mswin32]. It
barfed on "old_", so I substituted:
else
super(*args)
which worked fine.Best wishes,
Richard
Hi again,
I'm glad super worked out for you. That's the "right way" to do it
for inheritance.
I have a feeling I may have misguided you with the "alias old_ "
line. It should probably be something like "alias old_brackets " as
I doubt that old_ is a valid method name (I just checked and it
isn't, to be sure).
Dan
On Sun, May 4, 2008 at 4:40 PM, RichardOnRails <RichardDummyMailbox58407@uscomputergurus.com> wrote:
On May 3, 9:06 pm, Daniel Finnie <d...@danfinnie.com> wrote:
> Hi,
>
> You do this:
> class Array
> alias old_
> def *args
> if *args.length == 2 && args[0].is_a? Integer && args[1].is_a? Integer
> get(*args)
> else
> old_(*args)
> end
> end
>
> Of course, this would remove some of the functionality of an Array for
> every Array, not just matricies. Consider making a subclass of Array
> like this:
> class Matrix < Array
> ...
> end
>
> Now you can modify Matrix at will without affecting Array.
>
> If you are creating a Matrix for purely pragmatic reasons (i.e., not
> as an excercise) then there is an excellent Matrix class in the Ruby
> standard library:RDoc Documentation
>
> Dan
>
> On Sat, May 3, 2008 at 4:05 PM, RichardOnRails > > > > > <RichardDummyMailbox58...@uscomputergurus.com> wrote:
> > Hi,
>
> > I defined and populated a 9x9 matrix (Array of Arrays) of strings, m
>
> > I defined an element-extractor:
>
> > class Array
> > def get(i,j)
> > line =self[i-1]
> > char = line[j-1]
> > end
> > end
>
> > To get the first element of the second row, I used the following,
> > which worked fine:
>
> > m.get(2,1)
>
> > I'd like to write merely m(2,1). How can I do that simply?
>
> > Thanks in Advance,
> > RichardHi Daniel,
Thanks for the "kick start" and the Matrix class. I got the latter
working, but I'm going to "roll my own" because I want a Sudoku
solver that works the way I do manually. I know there's a free solver
written in VisualProlog, but like Frank Sinatra, "I'll do it my
way"> alias old_
I'm running ruby 1.8.6 (2007-09-24 patchlevel 111) [i386-mswin32]. It
barfed on "old_", so I substituted:
else
super(*args)
which worked fine.Best wishes,
Richard
Hi again,
I'm glad super worked out for you. That's the "right way" to do it
for inheritance.I have a feeling I may have misguided you with the "alias old_ "
line. It should probably be something like "alias old_brackets " as
I doubt that old_ is a valid method name (I just checked and it
isn't, to be sure).Dan
> > Hi,
> > You do this:
> > class Array
> > alias old_
> > def *args
> > if *args.length == 2 && args[0].is_a? Integer && args[1].is_a? Integer
> > get(*args)
> > else
> > old_(*args)
> > end
> > end> > Of course, this would remove some of the functionality of an Array for
> > every Array, not just matricies. Consider making a subclass of Array
> > like this:
> > class Matrix < Array
> > ...
> > end> > Now you can modify Matrix at will without affecting Array.
> > If you are creating a Matrix for purely pragmatic reasons (i.e., not
> > as an excercise) then there is an excellent Matrix class in the Ruby
> > standard library:RDoc Documentation> > Dan
> > > Hi,
> > > I defined and populated a 9x9 matrix (Array of Arrays) of strings, m
> > > I defined an element-extractor:
> > > class Array
> > > def get(i,j)
> > > line =self[i-1]
> > > char = line[j-1]
> > > end
> > > end> > > To get the first element of the second row, I used the following,
> > > which worked fine:> > > m.get(2,1)
> > > I'd like to write merely m(2,1). How can I do that simply?
> > > Thanks in Advance,
> > > Richard> Hi Daniel,
> Thanks for the "kick start" and the Matrix class. I got the latter
> working, but I'm going to "roll my own" because I want a Sudoku
> solver that works the way I do manually. I know there's a free solver
> written in VisualProlog, but like Frank Sinatra, "I'll do it my
> way"> > alias old_
> I'm running ruby 1.8.6 (2007-09-24 patchlevel 111) [i386-mswin32]. It
> barfed on "old_", so I substituted:
> else
> super(*args)
> which worked fine.> Best wishes,
> Richard
Hi Daniel,
Thanks for your additional response.
misguided
No problem! I misguide myself all the time Any, it's history.
I've got two questions about my current version of your code, which
works fine BTW.
1. Where is the get method come from. I looked in Ruby RDoc and (i)
see no get method for Array, nor (ii) any related get method on the
Methods section of the RDoc. I'd really like a pointer to it's
documentation. It certainly is useful in this context.
2. As I mentioned, I switched from "old_(*args)" in the else
clause to "super *args". which works fine for the most part. I works
fine, too, except I want to substitute "raise 'invalid data'" or
something more descriptive. Unfortunately, when I do that I get a
syntax error.
If you have the time, I'd love to get your take on these issues.
Code and output is below for your convenience.
Best wishes,
Richard
class Matrix < Array
def *args
if (args.length == 2) && args[0].is_a?(Integer) && args[1].is_a?
(Integer)
get(*args)
else
super *args
end
end
end
m = Matrix[ [10,20,30], [40,50,60], [70,80,90] ];
puts m [0] [1] # 20
puts m [2] [0] # 70
puts m[1] # 40
# 50
# 60
# This displayed nicely in my browser (Firefox 2.0). I hope it does
in yours!
On May 4, 5:44 pm, Daniel Finnie <d...@danfinnie.com> wrote:
On Sun, May 4, 2008 at 4:40 PM, RichardOnRails > > <RichardDummyMailbox58...@uscomputergurus.com> wrote:
> On May 3, 9:06 pm, Daniel Finnie <d...@danfinnie.com> wrote:
> > On Sat, May 3, 2008 at 4:05 PM, RichardOnRails > > > > <RichardDummyMailbox58...@uscomputergurus.com> wrote: