Rebol 3 Bazaar updates:

Well, these are the changes added to Rebol 3 Bazaar:

• changed bugs
• changed changes
• corrected demo, now launching demo, you'll obtain this:

• added demo in builds/windows, so you can understand new Rebol 3 styles
  
• added lasidlav correction of help string of exp and log-e
• Added r3-guir.r3 in build/windows/ directory, this way you don't need to load from internet; just launch  
  do %r3-gui.r3

• Added hostilefork suggestion to allow NEW-LINE and NEW-LINE? to accept PAREN! series
• Added earl fix parse thru end

Brett Handley

Today I write about Mr. Brett Handley, another great rebol activist.
Do you remember this post (http://rebol.informe.com/blog/2013/01/28/seeing-parse-in-action/)?
Mr. Brett Handley updated his scripts about parse analysis , read here:
http://www.rebol.org/cpt-list-scripts.r?user-name=brett

He said me:
There have been many changes. Simplification, speed up, reduced memory usage, bug fixes. A much more interactive display and a simple way to call it (visualise-parse). The other big change is that the new display now supports parsing in block mode (not just text).

Try his scripts downloading them from http://www.rebol.org/cpt-list-scripts.r?user-name=brett or visit his site: http://www.codeconscious.com/

Mandelbrot

Today we will talk of fractals, but what is a fractal?
It's like a image repeated so much that is the same zooming in or out, look the border of the following image, every line become a spike, but it's alway the same image repeated:

Well, science studies mathematically fractals since you may find fractals everywhere around you: leaves, minerals, galaxies.
The following scripts draw a Mandelbrot fractal, one of the best known:

REBOL [
    File: %mandelb.r
    Date: 19-Jul-2009
    Title: "Mandelbrot"
    Purpose: "Mandelbrot"
    Author: "Lami Gabriele"
    Email: koteth@gmail.com
]
x-siz: 400 y-siz: 400          
im: to-image layout [origin 0x0 box black to-pair x-siz y-siz]
bg-color: 200.200.210  
make-col: func[flo ][
    ic:   to-integer ( 10 * cosine ( erre * 100 ) )  
    ip:   to-integer ( 10 * ( 1 - cosine   ( erre * 100 ) )   )
    0.200.0 * ic   + ip   * 0.0.200 +   120.0.0
]
clear-im: func [im [image!] color [tuple!]][repeat j im/size/x * im/size/y [poke im j color] ]
set-pixel: func [im [image!] x [integer!] y [integer!] color [tuple!] ] [poke im (im/size/y - y * im/size/x + x) color ]
itmax: 30 minXPos: 0.0 minYPos: 0.0 zoom: 100.0 rmax: 3
norma: func[xx yy ] [square-root ((yy ** 2) + (xx ** 2)) ]
rescale: func[coo zoo offs ] [( coo / zoo ) + offs ]

calc-pixel: func [xPixel yPixel] [
    xStart: rescale xPixel zoom ( - 3.0 + minXPos ) yStart: rescale yPixel zoom ( - 2.0 + minYPos )  
    xcic: xStart ycic: yStart count: 0 r: 0.0  
    while [ r <= rmax and ( count < itmax ) ][
        xtem: (xcic ** 2 ) - (ycic ** 2) + xStart ycic: (2.0 * xcic * ycic ) + yStart
        r: norma xcic ycic xcic: xtem count: count + 1
    ]
    if (r < rmax)[return r ] return -1
]
view layout [
    text "threshold" tresInp: field to-string rmax
    text "iterations" iterInp: field to-string itmax
    text "zoom" zoomInp: field to-string zoom  
    text "x position" icsInp: field to-string minXPos  
    text "y position" ipsInp: field to-string minYPos  
    pgBar: progress 200x15 coal blue 0.0
   
    button "Draw" [
        zoom: to-decimal zoomInp/data itmax: to-integer iterInp/data
        minXPos: to-decimal icsInp/data minYPos: to-decimal ipsInp/data
        rmax: to-integer tresInp/data clear-im im bg-color
        repeat x x-siz [
            repeat y y-siz [
                erre: calc-pixel x y inrange: ( not-equal? erre -1 )
                if inrange[ set-pixel im x y make-col erre ]
            ]
            if ( x // 10 ) == 0   [show img ]
            pgBar/data: ( x / x-siz ) show pgBar
        ]
        show img
    ]
    at 240X10 img: image im
]                            


REBOL [
    Title: "Mandelbrot"
    Date: 21-Sep-2001
    Version: 0.0.1
    File: %mandelbrot.r
    Author: "Keith Ray"
    Purpose: "Create Mandelbrot Set "
    Email: %keithray--yahoo--com
]
clear-im: func [im [image!] color [tuple!]][
    repeat j im/size/x * im/size/y [poke im j color]
]
set-pixel: func [
    im [image!]
    x [integer!]
    y [integer!]
    color [tuple!]
    /local   x-siz y-siz siz
][
    x-siz: im/size/x
    y-siz: im/size/y
    poke im (y-siz - y * x-siz + x) color
]
calc-pixel: func [xPixel yPixel] [
    rmax: 2
    itmax: 100
    xStart: 0.00
    yStart: 0.00
    count: 0
    r: 0.00
    xnew: 0.00
    ynew: 0.00
    xold: 0.00
    yold: 0.00
    ;convert to real coordinates
    ;convert it to a value between -2.0 ... 1.0
    xStart: ( xPixel / 100.0 ) - 2.0
    ;convert it to a value between -2.0 ... 2.0
    yStart: ( yPixel / 100.0 ) - 2.0
    xold: xStart
    yold: yStart
    count: 0
    r:   0.0
    flag: 2
    while [flag > 1 ][
        flag: 0
        if ( r <= rmax )[flag: flag + 1 ]
        if ( count < itmax ) [flag: flag + 1 ]
        xnew: (xold * xold) - (yold * yold) + xStart
        ynew:   (2.0 * xold * yold) + yStart
        r: square-root ((xnew * xnew) + (ynew * ynew))
        xold: xnew
        yold:   ynew
        count: count + 1
    ]
    bol: false
    if (r < rmax)[bol: true]
    return bol
]
x-siz: 300 y-siz: 400          
im: make image! 300x400
bg-color: 255.255.220
clear-im im bg-color    
view layout [
    img: image im
    across
    pad 50
    button "Draw" [
    clear-im im bg-color
        repeat x x-siz [
            repeat y y-siz [
            if calc-pixel x y   [ set-pixel im x y blue ]
            ]
        show img
        ]
      show img
    ]
    button "Quit" [quit]
]


REBOL [
    Title: "Mandelbrot II"
    Date: 23-Sep-2001
    Version: 0.0.1
    File: %mandelbrot2.r
    Author: "Keith Ray"
    Purpose: "Create Mandelbrot Set with colors "
    Email: %keithray--yahoo--com
]
start-x: 2.0
start-y: 1.5
global-color: 0
clear-im: func [im [image!] color [tuple!]][
    repeat j im/size/x * im/size/y [poke im j color]
]
set-color: func [c ][
    switch c [
        1 [z: 0.0.0]
        2 [z: 20.0.0]
        3 [z: 40.0.0]
        4 [z: 60.0.0]
        5 [z: 80.0.0]
        6 [z: 100.0.0]
        7 [z: 120.0.0]
        8 [z: 140.0.0]
        9 [z: 160.0.0]
        10 [z: 180.0.0]
        12 [z: 180.20.0]
        22 [z: 180.40.0]
        13 [z: 180.60.0]
        14 [z: 180.80.0]
        15 [z: 180.100.0]
        16 [z: 180.120.0]
        17 [z: 180.140.0]
        18 [z: 180.160.0]
        19 [z: 180.180.0]
        20 [z: 160.180.0]
        21 [z: 140.180.0]
        22 [z: 120.180.0]
        23 [z: 100.180.0]
        24 [z: 80.180.0]
        25 [z: 60.180.0]
        26 [z: 40.180.0]
    ]
return z
]
set-outside-pixel: func [
    im [image!]
    x [integer!]
    y [integer!]
    colr [integer!]
    /local   x-siz y-siz siz
][
    x-siz: im/size/x
    y-siz: im/size/y
    color: set-color global-color
    poke im (y-siz - y * x-siz + x) color
   
]
set-pixel: func [
    im [image!]
    x [integer!]
    y [integer!]
    color [tuple!]
    /local   x-siz y-siz siz
][
    x-siz: im/size/x
    y-siz: im/size/y
    poke im (y-siz - y * x-siz + x) color
]
calc-pixel: func [xPixel yPixel] [
    rmax: 2
    itmax: 26
    xStart: 0.00
    yStart: 0.00
    count: 0
    r: 0.00
    xnew: 0.00
    ynew: 0.00
    xold: 0.00
    yold: 0.00
    ;convert to real coordinates
    ;convert it to a value between -2.0 ... 1.0
    xStart: ( xPixel / 100.0 ) - start-x
    ;convert it to a value between -2.0 ... 2.0
    yStart: ( yPixel / 100.0 ) - start-y
    xold: xStart
    yold: yStart
    count: 0
    r:   0.0
    flag: 2
    while [flag > 1 ][
        flag: 0
        if ( r <= rmax )[flag: flag + 1 ]
        if ( count < itmax ) [flag: flag + 1 ]
        xnew: (xold * xold) - (yold * yold) + xStart
        ynew:   (2.0 * xold * yold) + yStart
        r: square-root ((xnew * xnew) + (ynew * ynew))
        xold: xnew
        yold:   ynew
        count: count + 1
    ]
    bol: false
    if (r > rmax)[global-color: to-integer r]
    if (r < rmax)[bol: true]
    return bol
]
x-siz: 300 y-siz: 300          
im: make image! 300x300
bg-color: 255.255.220
clear-im im bg-color    
view layout [
    img: image im
    across
    pad 50
    button "Draw" [
    clear-im im bg-color
        repeat x x-siz [
            repeat y y-siz [
            either calc-pixel x y   [ set-pixel im x y black ][set-outside-pixel im x y y]
            ]
        show img
        ]
      show img
    ]
    button "Quit" [quit]
]


The Easiest Programming Language

Today I present another work of Nick Antonaccio: The Easiest Programming Language site
Obviously it talks about Rebol :-)
Moreover on his site he offers FREE private Rebol programming lesson, he wrote:

To introduce myself to new students and clients, I offer an absolutely free, private, no strings attached, one-one-one lesson and/or consultation, live online. If you'd like to take a free personal interactive lesson, if you'd like me to build you an application, or if you have any questions, you can get in touch with me 3 ways:

1. Go to http://rebolforum.com to ask questions in the forum.
2. Send an email to com2@com-pute.com, with the word "lessons" in the subject.
3. Leave me a phone message at 267-352-3625, if you live in the USA.

Well, now you know: Nick is one of the most prolific rebol activist.
Tomorrow I'll write about another activist.

send/only

Send/only permit to send message to many addresses with only a command, but how is the header?
Look here:
send/only [test@test.com maxint@tiscali.it] "Testing Rebol send/only"


The source of the email received will be:

From: MaxV
To:
Date: Wed, 27 Feb 2013 15:26:40 +0100
Subject: test Rebol send/only
X-REBOL: View 2.7.8.3.1 http://WWW.REBOL.COM

Testing Rebol send/only


As you noted the To: field is empty and there aren't other fields.
The best way in order to create beautiful mail is to create your custom header:

myheader: make object! [
    X-REBOL: "View 2.7.8.3.1 http://WWW.REBOL.COM"
    Subject:   "My subject"
    From:   maxint@tiscali.it
    Return-Path: maxint@tiscali.it
    To: "only for the secret R3B community..."
    Date: to-idate now   ;we must set a correct RFC 822 standard format date or our emails will be identified as spam
    MIME-Version:   "1.0"
        ]
send/header/only [maxint@tiscali.it test@test.it]   "Testing send/only again..." myheader

And you'll obtain:

X-REBOL: View 2.7.8.3.1 http://WWW.REBOL.COM
Subject: My subject
From: maxint@tiscali.it
To: only for the secret R3B community...
Date: 06/03/2013 15.11 MIME-Version: 1.0

Testing send/only again...




Cool!

Improved Search This Blog

I noticed that the blogger Search don't work well, so I replaced it with the http://rebol.informe.com/blog/ search engine.
Don't be scared, it just works better. Try it.

Magic 8 ball

Do you remember the magic 8 ball?
If not you can read this http://en.wikipedia.org/wiki/Magic_8-Ball about this ball that help yo to take decisions.
Well, the following script is a very simple example of recreate that:

Rebol []
random/seed now
sentences: [
    "As I see it, yes"
    "It is certain"
    "It is decidedly so"
    "Most likely"
    "Outlook good"
    "Signs point to yes"
    "Without a doubt"
    "Yes"
    "Yes – definitely"
    "You may rely on it"
    "Reply hazy, try again"
    "Ask again later"
    "Better not tell you now"
    "Cannot predict now"
    "Concentrate and ask again"
    "Don't count on it"
    "My reply is no"
    "My sources say no"
    "Outlook not so good"
    "Very doubtful"
    ]
   
view   layout [
    h1 "Ask the magic ball"
   
    button "ASK" [  
    a: pick   sentences (random 20)
    answer/text: a
    answer/color: random 255.255.255
    show answer
    ]
    answer: vtext "________________________"
    ]