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this file uses UTF-8 encoding
A+ employs 0-origin indexing
and the index origin is always 0
when using firefox to view text pages about aplus use
KAPL font with UTF-8 encoding
when editing this file aplus-notes.txt use kedit
with KAPL font and UTF-8 encoding
use kedit to edit aplus scripts but use
LC_ALL=ISO-8859-1
examples of aplus in this file can be clipboarded and run
in aplus
when using aplus:
xmodmap usapl.txt necessary to get the alt key to work as expected
export LANG=en_GB.iso8859 this may be necessary for scripts
export LC_ALL=ISO-8859-1 this may be necessary for scripts
system variable names begin with `.
examples in ~/Downloads/aplus-fsf-4.22/src/a
environment variables are $ATREE and $APATH
keys specific to aplus
----------------------
alt shift c generates the comment character, everything on that line is a comment
alt shift 4 generates the sort symbol è
alt shift 5 gives circle with vertical line ÷
alt shift 6 gives transpose ô
alt shift f gives depth ½
alt shift 8 gives natural log ð
alt shift b gives execute â
alt shift a gives á
alt shift n gives format î
alt 1 generates each ¡
alt 2 generates high minus ¢
alt 3 generates enclose <
alt 7 generates greater than >
alt 8 generates not equal ¨
alt 9 generates logical or © or monadic type
alt 0 generates logical and ^
alt [ gives û operator
alt ] gives ý operator (clears error, $ also clears error)
alt - gives multiply «
alt = gives divide ß
alt shift = gives matrix divide
alt / gives ¯
alt s gives ceiling Ó
alt d gives floor Ä
alt u gives drop Õ
alt y gives take Ù
alt n gives encode Î
alt b gives decode Â
alt i gives interval É
alt e gives member Å
alt ` gives diamond þ
alt ' gives left Ý
alt ; gives right Û
alt v gives separate symbols Ö
alt q gives ?
alt l gives box Ì
alt o gives pi times Ï
alt r gives reshape Ò
alt z gives partition/partition count Ú
alt x gives pick/raze Ø
$load s loads screen management facilities
$load disp load display function
$load loop.+
load an apl program and execute it
$load prime.a
load user function prime into workspace
operating system commands in general can be accessed by preceeding
the $ symbol before it:
$date
$time
in other versions of APL the box symbol is used for built-in
variables, but in aplus $ is used instead:
$pp returns the number of digits of precision which is 10
$cd /home/cubeman
change directory to home directory
$clear clears screen
$mode returns current mode (e.g. apl or ascii or uni)
$off logs out of aplus
$vars returns all the variables
$sfs returns system function names
$fns returns all functon names
$si state indicator
$vers returns version of aplus
$reset reset all suspensions
$mode ascii
set ascii mode
$ops list operators
$cmds list all commands
$globs list all global objects
$cxs display a list of all the context names
$cx c switch to context c
$cx . return to root context
$Gf 1 sets protected mode on
É10 returns the numbers 0 to 9
«/(É10)+1 returns 10 factorial
+\É5 returns 0 1 3 6 10
(É50)+50 returns the numbers 50 to 99
| ¢5 returns absolute value, e.g. 5
3 3 Ò É9
returns the numbers 0 to 8 in a 3x3 matrix
v û 3 3 Ò É9
+/ v sum the columns
+/@1 v sum the rows
a û 'gerbie power'
#a returns the number of characters or 12
Trail û 'Going to the trail'
variable names are case sensitive
ô2 6Ò 'Hello World!'
returns Hello World! vertically
a û 'apple'
b û 'pear'
c û a,b stores applepear in c
2ð1 2 4 8 16 32
returns log of 2, i.e. 0 1 2 3 4 5
+/2|3 4 5 6 7
returns the number of odd integers, i.e. 3
«\5Ò2 returns 2 4 8 16 32
+\+\5Ò1 returns 1 3 6 10 15
÷(É5)+1 returns 5 4 3 2 1
?3 returns a random number from 0 to 2
100 ? 100 generates 100 random numbers from 0 to 99
12/4 generate 12 4's
4 / 'abc' generates aaaabbbbcccc
table û 3 3 Ò 1 2 3 4 5 6 7 8 9
table[2;2] returns 9
Ò table returns 3 3
c.b <- 'abcdef'
store abcdef in b in the context of c
%`a display a in the root context
%`c.b display b in the c context
xûÉ3 5 6 create 3 dimension array x
x[0;0;0]û50 set the element at coordinates (0,0,0) to 50
aûÉ3 4 create 3x4 array with elements 0 to 11
a[]û5 set all elements of array to 5
,a returns a unravelled into a straight line vector
a û 1 2 3
a[,] û 4 append 4 to array a
Òa returns 4
ÒÒÉ4 5 returns 2 (number of dimensions)
5ß(Õ2) the drop symbol Õ prints the expression following it
this line returns 2.5
2
1 2 3 Ê.+ 4 5 6
outer product of +
+ Í 4 5 6
---Í---------
1 Í 5 6 7
2 Í 6 7 8
3 Í 7 8 9
1 2 3 Ê.« 4 5 6
outer product of «
x û 'gerbil'
xÊ.=x
use outer product of = to compare every character of x to
every other character
1 0 0 0 0 0
0 1 0 0 0 0
0 0 1 0 0 0
0 0 0 1 0 0
0 0 0 0 1 0
0 0 0 0 0 1
v û 1 2 3 4 5
v[0 1 4] returns 1 2 5
+/v returns sum across v
+\v returns running sum across v
wû1 2 ¢4 12 0 ¢7 14 2 ¢3
+/(w>0)«w
returns sum of the positive numbers in w
(w>0)+.«w shorter method doing the same thing
xû1 1 1 0 1 1 0 1
+/^\x returns index of the first zero, i.e. 3
v û 3 3 5 6 7 8 1 9 3 4 5 7 7
((vÉv)=É#v)/v
returns only unique values of v,
i.e. 3 5 6 7 8 1 9 4
nû10
xûn do Õn returns numbers 0 to 9
xû(nû10) do Õn
same thing on one line
z û 0
n û 10
n do zûz,n+1
returns 0 to 10
' ' ¨ 'this is it'
returns 1 1 1 1 0 1 1 0 1 1
aû1
bû0
a © b returns 1 (or)
a ^ b returns 0 (and)
4« `arctan Ï1
returns pi
Ï1 returns pi times 1
`sin Ï1 returns 0.8414709848
1Ï1 returns 0.8414709848 (same as above)
`cos Ï1 returns 0.5403023059
(a; b; c) û 1 2 3
strand or multi-assignment a is 1, b is 2 and c is 3
(a; b; c) û 1
a b and c are all set to 1
a, b, c returns 1 2 3
aû1; bû2; cû3;
multiple statements on one line are separated by ;
v û 1 2 3 4 5
÷v returns reverse order of v
m û 'gerbie power'
3 ÷ m returns bie powerger (rotates 3 characters to the left)
a û 1 2 3
1 ÷ a returns 2 3 1
¢5Õ 'test12345'
returns test (drops last 5 characters)
5Õ 'test12345'
returns 2345 (drops first 5 characters)
'abc'Ý2 3 returns abc
a[èa] Ý aû'barforoni'
returns abfinoorr (characters are sorted)
a û 14 56 34 11 0 ¢2 1
a[èa] returns ¢2 0 1 11 14 34 56 (numbers are sorted)
÷a[èa] returns 56 34 14 11 1 0 ¢2 (numbers are sorted in reverse order)
a[ça] same as above
'cat' Å 'hat'
returns 0 1 1
2 0 # 3 3Ò'abcdefghi'
returns ghi (returns row 2 and row 0)
abc
24 60 60Â1 7 0
returns 4020
convert 1 hour and 7 minutes to seconds
10 10 10 Â 1 1 1
returns 111
8 8 8 Â 1 2 3
convert octal number 123 to decimal (returns 83)
2 2 2 Â 1 0 0
convert binary number 100 to decimal (returns 4)
1 < 2 returns 1 (true)
1 > 2 returns 0 (false)
mean x: (+/x)ß#x
mean 1 2 3 4 5 6 7 8 9 10
returns 5.5
f{}:'abc' f{} returns abc
drop5 string : ¢5Õ string
this is a function, e.g. drop5 'pumpkin' returns pu
3ÙÉ10 takes the first 3 items of É10
¢3ÙÉ10 takes the last 3 items of É10
a û É¡ 3 4 5
a contains vectors É3, É4, and É5
s û'this is a test'
bûs=' '
b returns 0 0 0 0 1 0 0 1 0 1 0 0 0 0
(Ú1,b)Ús returns separate words in s
ôÉ3 3 transpose x and y elements
aû1.42
1|a returns factional part of a
â 'v û 1 2 3 4 5'
execute a string
1 + â '1' convert character '1' to a number and add 1
b ý '2'
a û â b convert character array b to int and store in a
aû10
bû17
a+É1+b-a returns 10 11 12 13 14 15 16 17
© 'abc' returns `char which is the type
© < 'abc' returns `box
© _argv returns `box
© `abc returns `sym
© () returns `null
b û 'twinkie'
c û ' '
d û 'power'
e û Ø (b; c; d)
e becomes twinkie power
<'abc' enclose a string, returns < abc
><'abc' discloses an enclosed string which returns the string
½<'abc' returns depth of enclosed string, e.g. 1
`int©3.4 4.5 5.6
cast float as integer, returns 3 5 6
`char©97 returns ascii character 97
a û 1
b û î a store a as text in b
© b returns `char
v û '$vars'
âv commands can be placed in variables and executed
2Ò¡ 3 4 5 < 3 3
< 4 4
< 5 5
w û É¡1 2 3 4
< 0
< 0 1
< 0 1 2
< 0 1 2 3
2Ò< 'cat'
< cat
< cat
4!'fourbeartops'
restructure string into 3 strings of 4 characters
¢3!v restructure v into 3 parts
a û (1 2 ; 'abc' )
create nested array and store in a
vû 53 14 27 2 31 85 30 11 67 50
gû`v
show `g is `graph
display graph of g
`g has (`title;"Graph Tutorial Example")
give graph a title
show v displays vector v in a window
t û 'test'
show t as `text
displays text in a window
$load disp
disp.lay (10 32;'abc')
disp.lay 2 2 Ò É4
a û 1 2 3 4 5
disp.int (a)
sets up a display of an integer array
b û 'the power of gerbie'
disp.char (b)
sets up a display of a string
disp.enbox (b)
sets up a string with a simple box
disp.disp (x)
displays any type of array or function
disp.disp (a;b;c)
display arrays a b and c
m û 1.234
disp.float (m)
sets up a display of a floating point array
$fns disp list functions in context disp
$fns s list functions in context s
$load box
$fns box list functions in context box
box.in
$load t
t.tile show tile function
t.calendar show calendar function '$load dio' beforehand
t.calendar ('01/01/2013 ý 01/02/2013')
argument is a character vector in the form of mm/dd/yyyy
function returns an integer vector:
20130101 20130102 20130103
t.intersect {v ; w }
v and w can have integer or character data
curly braces must be used
show elements common to v and w
t.unique {'apple'}
returns aple
t.file_exists {'/home/cubeman/text/wine.txt'}
returns 1
dio.parse ('12/12/2013')
20131212 ¢999999999
if(`int=©4294967296) wordsizeû64 else wordsizeû32;
returns wordsize
$load s
s.CDE returns 1 if running the CDE window manager, otherwise return 0
s.reset{} free all objects (has the effect of closing all windows)
mûsys.readmat{'prime.a'}
read text file into character variable m
sys.sleep{10} sleep for 10 seconds
sys.filesize{'yum.txt'}
returns size of file yum.txt
sys.gethostname{}
returns name of current host machine
sys.readenv {"HOME"}
returns /home/cubeman
sys.username {0}
sys.getpid{} returns pid of a+
sys.system('cd $HOME')
sys.system executes system calls
sys.system('sh')
drop to bash shell
returns username corresponding to the user id, e.g. root
'g<99:99:99>' _fmt 100Â3Ù3Õsys.ts{}
returns time in 24 hour format
_gsr{'apple is';'is'; 'is not';''}
global search and replace, 'is' is replaced with 'is not'
_load 'disp' loads script file and reports full pathname
_nl{`disp; `vars}
named list, lists variables in context disp
_nl{`;`cxs} list all contexts
_nl{`;`apl} list all keywords and symbols for APL mode
_nl{;Ï} list all circle functions
multi-line functions
--------------------
total m: {