LED is my new Hello World - ABAP Time

It's been a long time since I did any ABAP development...so just for the good all times I decided to build the LED Number application on ABAP as well... -;)

I'm might be a little bit rusty...but I think I still remember most of the all tricks -:P

This goes out to all my ABAP friends...there are plenty -:)

ZLED
REPORT zled. TYPES: BEGIN OF ty_lines, line(1) TYPE c, index(1) TYPE c, map TYPE string, END OF ty_lines. DATA: s_number TYPE string, counter TYPE i, num_counter TYPE i, line1 TYPE string, line2 TYPE string, line3 TYPE string. DATA: t_lines TYPE STANDARD TABLE OF ty_lines. FIELD-SYMBOLS: <fs_lines> LIKE LINE OF t_lines. SELECTION-SCREEN BEGIN OF BLOCK params. PARAMETERS: p_number TYPE i. SELECTION-SCREEN END OF BLOCK params. START-OF-SELECTION. PERFORM load_data. num_counter = 0. s_number = p_number. counter = strlen( s_number ) - 1. DO counter TIMES. READ TABLE t_lines ASSIGNING <fs_lines> WITH KEY line = 1 index = s_number+num_counter(1). CONCATENATE line1 <fs_lines>-map INTO line1 SEPARATED BY space. READ TABLE t_lines ASSIGNING <fs_lines> WITH KEY line = 2 index = s_number+num_counter(1). CONCATENATE line2 <fs_lines>-map INTO line2 SEPARATED BY space. READ TABLE t_lines ASSIGNING <fs_lines> WITH KEY line = 3 index = s_number+num_counter(1). CONCATENATE line3 <fs_lines>-map INTO line3 SEPARATED BY space. num_counter = num_counter + 1. ENDDO. REPLACE ALL OCCURRENCES OF '%' IN line1 WITH ` ` IN CHARACTER MODE. REPLACE ALL OCCURRENCES OF '%' IN line2 WITH ` ` IN CHARACTER MODE. REPLACE ALL OCCURRENCES OF '%' IN line3 WITH ` ` IN CHARACTER MODE. WRITE:/ line1. WRITE:/ line2. WRITE:/ line3. *&---------------------------------------------------------------------* *& Form LOAD_DATA *&---------------------------------------------------------------------* FORM load_data. PERFORM add_lines USING '1' '0' '%_%%'. PERFORM add_lines USING '2' '0' '| |%'. PERFORM add_lines USING '3' '0' '|_|%'. PERFORM add_lines USING '1' '1' '%%'. PERFORM add_lines USING '2' '1' '|%'. PERFORM add_lines USING '3' '1' '|%'. PERFORM add_lines USING '1' '2' '%_%%'. PERFORM add_lines USING '2' '2' ' _|%'. PERFORM add_lines USING '3' '2' '|_%%'. PERFORM add_lines USING '1' '3' '_%%'. PERFORM add_lines USING '2' '3' '_|%'. PERFORM add_lines USING '3' '3' '_|%'. PERFORM add_lines USING '1' '4' '%%%%'. PERFORM add_lines USING '2' '4' '|_|%'. PERFORM add_lines USING '3' '4' ' |%'. PERFORM add_lines USING '1' '5' '%_%%'. PERFORM add_lines USING '2' '5' '|_ %'. PERFORM add_lines USING '3' '5' ' _|%'. PERFORM add_lines USING '1' '6' '%_%%'. PERFORM add_lines USING '2' '6' '|_%%'. PERFORM add_lines USING '3' '6' '|_|%'. PERFORM add_lines USING '1' '7' '_%%'. PERFORM add_lines USING '2' '7' '%|%'. PERFORM add_lines USING '3' '7' '%|%'. PERFORM add_lines USING '1' '8' '%_%%'. PERFORM add_lines USING '2' '8' '|_|%'. PERFORM add_lines USING '3' '8' '|_|%'. PERFORM add_lines USING '1' '9' '%_%%'. PERFORM add_lines USING '2' '9' '|_|%'. PERFORM add_lines USING '3' '9' ' _|%'. ENDFORM. " LOAD_DATA *&---------------------------------------------------------------------* *& Form add_lines *&---------------------------------------------------------------------* FORM add_lines USING p_line p_index p_map. APPEND INITIAL LINE TO t_lines ASSIGNING <fs_lines>. <fs_lines>-line = p_line. <fs_lines>-index = p_index. <fs_lines>-map = p_map. ENDFORM. "add_lines

Pics or it didn't happen -:)

Greetings,

Blag.

Development Culture.

LED is my new Hello World - R Time

Yep...as I have said many times before, the LED Number application has become my new Hello World...whenever I learn a new programming language I try to build this, because it compromises several language constructs and makes you learn more by trying to figure out how to build it again...

Yesterday I blog about how to build it using Haskell...and...I'm still learning Haskell...so I thought..."It's cool that I'm using this for my new programming languages...but what about the old ones?"

I suddenly realized that I had never wrote this using R...and that's really sad...I love R -:)

Anyway...here it goes -;)

LED.R
line<-c(1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3) index<-c(0,0,0,1,1,1,2,2,2,3,3,3,4,4,4,5,5,5,6,6,6,7,7,7,8,8,8,9,9,9) map<-c(" _ ","| | ","|_| "," ","| ","| "," _ "," _| ","|_ ", " _","_| ","_| "," ","|_| "," | "," _ ","|_ "," _| ", " _ ","|_ ","|_| "," _ "," | "," | "," _ ","|_| ","|_| ", " _ ","|_| "," _| ") Lines<-cbind(line,index,map) DF_Lines<-data.frame(Lines,stringsAsFactors=F) line1<-"" line2<-"" line3<-"" p_number<-readline("Enter a number?: ") l_number<-strsplit(p_number,"") for(i in 1:nchar(p_number)){ num_map<-DF_Lines[DF_Lines$index == as.numeric(l_number[[1]][i]),] line1<-paste(line1,num_map$map[1]) line2<-paste(line2,num_map$map[2]) line3<-paste(line3,num_map$map[3]) } lines = paste(line1,"\n",line2,"\n",line3,"\n") cat(lines)

Check the picture -;)

Greetings,

Blag.

Development Culture.

My first post on Haskell

So...as I get into functional programming thanks to Erlang...I decided to deep dive into Haskell...a pure functional programming language...

Of course...I'm reading a book for this...so when I finished it...which will take some time as I'm planning to start reading from the very first page again...soon you will read my review on Learn You a Haskell for Great Good...

Now...Haskell is hard...the hardest programming language I have ever dared to learn...and here's a couple of reasons why...

• Variables are immutable...once assigned they cannot be re-assigned.
• Functions only accept one parameter and one parameter only.
• Functions can only call one function at a time.
• There are no loops.
• No side effects...everything is pure...a function will always return the same output

There's a really nice picture from XKCD explaining Haskell...

Anyway...Haskell makes you really forget everything you ever learn and make you learn everything again...for a developer like me...that's pure happiness -:)

So...I have done with already Ruby, Python, Julia and Erlang...I wanted my first Haskell application to be a LED Numbers application...so here goes the code...hang to you seat and watch this...BTW...I'm sure the code can be optimized...but I'm just a newbie...and my application works...so who cares about it -;)

LED.hs
showLED :: Int -> IO() showLED(num) = do putStr(concat(addN(get_led(digits num) 1 num) (length(show num)) (length(show num)))) get_led :: [Int] -> Int -> Int -> [[Char]] get_led (x:xs) n num = make_led_digit(x,n) ++ get_led(xs) n num get_led [] n num = get_led2(digits num) (n+1) num get_led2 :: [Int] -> Int -> Int -> [[Char]] get_led2 (x:xs) n num = make_led_digit(x,n) ++ get_led2(xs) n num get_led2 [] n num = get_led3(digits num) (n+1) num get_led3 :: [Int] -> Int -> Int -> [[Char]] get_led3 (x:xs) n num = make_led_digit(x,n) ++ get_led3(xs) n num get_led3 [] n num = [] digits :: Int -> [Int] digits = map (read . (:[])) . show addN :: [String] -> Int -> Int -> [String] addN (x:xs) n ni | n > 0 = [x] ++ addN xs (n-1) ni | n == 0 = ["\n"] ++ [x] ++ addN xs (ni-1) ni addN [] _ _ = [] ++ ["\n"] make_led_digit :: (Int, Int) -> [[Char]] make_led_digit(0,1) = [" _ "]; make_led_digit(0,2) = ["| | "]; make_led_digit(0,3) = ["|_| "]; make_led_digit(1,1) = [" "]; make_led_digit(1,2) = ["| "]; make_led_digit(1,3) = ["| "]; make_led_digit(2,1) = [" _ "]; make_led_digit(2,2) = [" _| "]; make_led_digit(2,3) = ["|_ "]; make_led_digit(3,1) = ["_ "]; make_led_digit(3,2) = ["_| "]; make_led_digit(3,3) = ["_| "]; make_led_digit(4,1) = [" "]; make_led_digit(4,2) = ["|_| "]; make_led_digit(4,3) = [" | "]; make_led_digit(5,1) = [" _ "]; make_led_digit(5,2) = ["|_ "]; make_led_digit(5,3) = [" _| "]; make_led_digit(6,1) = [" _ "]; make_led_digit(6,2) = ["|_ "]; make_led_digit(6,3) = ["|_| "]; make_led_digit(7,1) = ["_ "]; make_led_digit(7,2) = [" | "]; make_led_digit(7,3) = [" | "]; make_led_digit(8,1) = [" _ "]; make_led_digit(8,2) = ["|_| "]; make_led_digit(8,3) = ["|_| "]; make_led_digit(9,1) = [" _ "]; make_led_digit(9,2) = ["|_| "]; make_led_digit(9,3) = [" _| "]

Here's a picture that show how it works...

I will keep learning Haskell and write another blog called "Decimals to Roman - Haskell Style"...stay tuned -;)

UPDATE!

Ok...I must face it...I couldn't leave the application like that knowing that I could make better...here's the new updated version -;)

LED_Fixed.hs
showLED :: Int -> IO() showLED(num) = do putStr(concat(addN(get_led(digits num) 1 num) (length(show num)) (length(show num)))) get_led :: [Int] -> Int -> Int -> [[Char]] get_led (x:xs) n num = make_led_digit(x,n) ++ get_led(xs) n num get_led [] n num | n < 3 = get_led(digits num) (n+1) num | n == 3 = [] digits :: Int -> [Int] digits = map (read . (:[])) . show addN :: [String] -> Int -> Int -> [String] addN (x:xs) n ni | n > 0 = [x] ++ addN xs (n-1) ni | n == 0 = ["\n"] ++ [x] ++ addN xs (ni-1) ni addN [] _ _ = [] ++ ["\n"] make_led_digit :: (Int, Int) -> [[Char]] make_led_digit(0,1) = [" _ "]; make_led_digit(0,2) = ["| | "]; make_led_digit(0,3) = ["|_| "]; make_led_digit(1,1) = [" "]; make_led_digit(1,2) = ["| "]; make_led_digit(1,3) = ["| "]; make_led_digit(2,1) = [" _ "]; make_led_digit(2,2) = [" _| "]; make_led_digit(2,3) = ["|_ "]; make_led_digit(3,1) = ["_ "]; make_led_digit(3,2) = ["_| "]; make_led_digit(3,3) = ["_| "]; make_led_digit(4,1) = [" "]; make_led_digit(4,2) = ["|_| "]; make_led_digit(4,3) = [" | "]; make_led_digit(5,1) = [" _ "]; make_led_digit(5,2) = ["|_ "]; make_led_digit(5,3) = [" _| "]; make_led_digit(6,1) = [" _ "]; make_led_digit(6,2) = ["|_ "]; make_led_digit(6,3) = ["|_| "]; make_led_digit(7,1) = ["_ "]; make_led_digit(7,2) = [" | "]; make_led_digit(7,3) = [" | "]; make_led_digit(8,1) = [" _ "]; make_led_digit(8,2) = ["|_| "]; make_led_digit(8,3) = ["|_| "]; make_led_digit(9,1) = [" _ "]; make_led_digit(9,2) = ["|_| "]; make_led_digit(9,3) = [" _| "]

Greetings,

Blag.
Development Culture.

Programming Erlang Software for a Concurrent World - Book Review

I just finished reading Programming Erlang Software for a Concurrent World by Joe Armstrong...the creator of Erlang.

Nothing better that reading about a language, from the mouth of it's creator -:)

The book is huge with 519 pages...but every single page is worth reading...full of nice, funny and well explained examples, Mr. Armstrong makes you love Erlang -:)

Learn about Sequential Programming, Concurrent Programming, Distrubuted Programming, Sockets, DETS, OTP and Mnesia...among others...

This book is just great and I have learned so much...of course...while I'm still an Erlang newbie..I have enough knowledge to build small applications and have a lot of fun -;)

What I like about the book is that the approach is very light and casual...the example are not too easy or too hard, so using them to learn is just right...

Erlang is a language is that more than worth learning...and this book really does the job of hooking you up and getting ready for more...

Greetings,

Blag.
Development Culture.

Bioinformatics with R Cookbook - Book Review

I just finished reading Bioinformatics with R Cookbook...so here's my review -:)

I was excited to read this book, because it's been a while since I read any R book...but...I gotta admit...this is not my kind of book...as I discovered that obviously I had minus one experience in Bioinformatics...

The book is not short but not long either...340 pages...and it's full of recipes...

It starts with a basic introduction to R, which should be appreciated by newbies...but for more season developers that just can be skipped out...

The are chapters dedicated to Sequence Analysis, Protein Structure Analysis and even Machine Learning in Bioinformatics...

Of course there's a lot of new packages that are used for the recipes and well as many interesting graphics...

If you have some knowledge of Bioinformatics...then you should for sure get this book...if you're not...well...you can buy it anyway...even if you don't understand anything...it is still a book about R and it's full of interesting codes...so you might end learning a bunch of new things -;)

The recipes are well explained and the result is always shown...which is good so we can know exactly what to expect...

Greetings,

Blag.

Development Culture.

Decimal to Romans - Erlang Style

As I keep going with my Erlang enlightenment...I decided to try to make a Decimal to Roman Numbers application...as I have done with other programming languages in the past...and it wasn't that easy -:)

First...there's no such thing as associative arrays in Erlang...also...you can only assign variables once...on top of that there's no loops...but...who cares...functional programming is cool -;)

Of course...my code might be have done better...but...I'm learning...and by coding I learn more...so that's fine with me...

Here's why I wrote -;)

roman_numerals.erl
-module(roman_numerals). -export([showRomans/1]). -define(DECIMALS,{1000,900,500,400,100,90,50,40,10,9,5,4,1}). showRomans(Number) when is_integer(Number) -> showRomans(Number,1,""). showRomans(0,_,Acc) -> io:format("~s~n",[Acc]); showRomans(Number,Counter,Acc) -> case Number >= element(Counter,?DECIMALS) of true -> showRomans(Number - element(Counter,?DECIMALS), Counter,Acc ++ make_roman(element(Counter,?DECIMALS))); false -> showRomans(Number,Counter + 1,Acc) end. make_roman(1) -> "I";make_roman(4) -> "IV";make_roman(5) -> "V"; make_roman(9) -> "IX";make_roman(10) -> "X";make_roman(40) -> "XL"; make_roman(50) -> "L";make_roman(90) -> "XC";make_roman(100) -> "C"; make_roman(400) -> "CD";make_roman(500) -> "D";make_roman(900) -> "CM"; make_roman(1000) -> "M".

When we execute it...we can see that it works nicely -;)

As you can see...Erlang is all about functions, recursion, accumulators and a new way of thinking -:)

Greetings,

Blag.
Development Culture.

A trip down memory lane - Basic for Macintosh Plus

Many years ago...in the good old days...my first computer was a Macintosh Plus...

Of course...back then I didn't have a clue about programming...but...thanks to the wonderful world of the Internet I was able to get my hands on a Macintosh Plus Emulator called Mini vMac.

I got it a couple of years ago but barely used it...so today...I wanted to get the feeling of old programming by using...

Yep...Microsoft Basic 2.0 for the Mac...

This is how the environment of the Mini vMac looks like...using MacOS 7.0.1

As I have been using the LED example for many programming languages...I thought it would be a good idea to use it here as well...

The output doesn't look to good...but who cares -;)

Here's the source code in case you're interested -:D

LED
Dim Five$(2) Dim Six$(2) Dim Seven$(2) Dim Eight$(2) Dim Nine$(2) Zero$(0) = " _ " Zero$(1) = "| | " Zero$(2) = "|_| " One$(0) = " " One$(1) = "| " One$(2) = "| " Two$(0) = " _ " Two$(1) = " _| " Two$(2) = "|_ " Three$(0) = "_ " Three$(1) = "_| " Three$(2) = "_| " Four$(0) = " " Four$(1) = "|_| " Four$(2) = " | " Five$(0) = " _ " Five$(1) = "|_ " Five$(2) = " _| " Six$(0) = " _ " Six$(1) = "|_ " Six$(2) = "|_| " Seven$(0) = "_ " Seven$(1) = " |" Seven$(2) = " |" Eight$(0) = " _ " Eight$(1) = "|_| " Eight$(2) = "|_| " Nine$(0) = " _ " Nine$(1) = "|_| " Nine$(2) = " _| " INPUT "Enter a Number: ", Number$ NumLen = LEN(Number$) FOR i = 1 to NumLen Digit$ = MID$(Number$,i,1) IF Digit$ = "0" THEN line1$ = line1$ + Zero$(0):line2$ = line2$ + Zero$(1):line3$ = line3$+Zero$(2) IF Digit$ = "1" THEN line1$ = line1$ + One$(0):line2$ = line2$ + One$(1):line3$ = line3$+One$(2) IF Digit$ = "2" THEN line1$ = line1$ + Two$(0):line2$ = line2$ + Two$(1):line3$ = line3$+Two$(2) IF Digit$ = "3" THEN line1$ = line1$ + Three$(0):line2$ = line2$ + Three$(1):line3$ = line3$+Three$(2) IF Digit$ = "4" THEN line1$ = line1$ + Four$(0):line2$ = line2$ + Four$(1):line3$ = line3$+Four$(2) IF Digit$ = "5" THEN line1$ = line1$ + Five$(0):line2$ = line2$ + Five$(1):line3$ = line3$+Five$(2) IF Digit$ = "6" THEN line1$ = line1$ + Six$(0):line2$ = line2$ + Six$(1):line3$ = line3$+Six$(2) IF Digit$ = "7" THEN line1$ = line1$ + Seven$(0):line2$ = line2$ + Seven$(1):line3$ = line3$+Seven$(2) IF Digit$ = "8" THEN line1$ = line1$ + Eight$(0):line2$ = line2$ + Eight$(1):line3$ = line3$+Eight$(2) IF Digit$ = "9" THEN line1$ = line1$ + Nine$(0):line2$ = line2$ + Nine$(1):line3$ = line3$+Nine$(2) NEXT i PRINT line1$ PRINT line2$ PRINT line3$

The code might not be the most optimal...but what can you expect? It's basic...old basic -:P

Greetings,

Blag.
Development Culture.

Learn You Some Erlang for great good! - Book review

Today...just a couple of minutes ago...I finished reading Learn You Some Erlang for great good! and I must say...I'm both joyful and tired -:)

The book is huge...not kidding...it's "OMFG this book is huge"...with 628 pages...and lots...lots of examples...

This book is so good that it's actually considered part of the Erlang standard documentation...or something like that...or at least...that's how I think it should be considered...

The book starts with the basics of Erlang (the one's that make you brain hurt)...and then keeps moving forward introducing things like Concurrency, Multiprocessing, Supervisors, OTP, Event Handlers and more...much more...

Reading this book will give all the tools and knowledge necessary to start building applications...

If you have never heard of Erlang before and want to give it a try...this is totally the book for you...but...a word of warning...this book is full of content...that it could easily overwhelm you and make your brain hurt even more...

Now that I have finished the book...I think I will constantly come back to re-read some chapters as I need them...gladly...with some many examples it's easy to grasp most of the concepts at least in a slight way...

Of course...I'm still a newbie...so my next book (with review of course) it's going to be Programming Erlang (Software for a Concurrent World) written by Joe Amstrong (one the creators of Erlang)...

Oh...BTW...you can read Learn You Some Erlang for great good! online

Greetings,

Blag.

Development Culture.