rpn - Reverse Polish Notation language
rpn
- is a math-oriented language inspired by Hewlett-Packard Reverse Polish Lisp (HP28S user manual is provided as a reference), it includes at least stack, store, branch, test, trig and logs commands
- brings powerfull calculation facilities on floating point numbers with arbitrary precision, provided by GNU MPFR library
- uses that so cool reverse polish notation
Quick examples:
- easy calculation with stacked results
rpn> 1 exp 3 *
8.1548454853771357061
rpn> 2 sqrt
2> 8.1548454853771357061
1> 1.4142135623730950488
rpn>
- programs and variables, eg same example as in HP28S Quick Reference:
rpn> << rot * swap 2 / chs dup sq rot - sqrt >> 'quadratic_solution' sto
rpn> 1 2 -3 quadratic_solution
2> -1
1> 2
rpn> vars
var 1: name 'quadratic_solution', type program, value << rot * swap 2 / chs dup sq rot - sqrt >>
- local variables, always from the same reference:
rpn> << -> x y << x y + ln >> >> 'P' sto
rpn> 1 2 P
rpn> 1.0986122886681096914
- arbitrary precision (up to 0x7FFFFFFFFFFFFFFF bits with GNU MPFR !)
rpn> 256 prec 200 std
rpn> pi 3 * 4 / cos
-0.70710678118654752440084436210484903928483593768847403658833986899536623923105962592591087473479525356117497671223960240783675485777817360566073272153486395308799122357513534343724299243077135552002446
rpn>
- Following objects are managed: floating numbers, symbols, strings, programs, plus language keywords (commands and flow controls)
4> 'symbol'
3> "string"
2> 12.3456
1> << -> n << 0 1 n for i i 2 * inv + next >> >>
rpn>
- A GNU-readline-based interactive editor with autocompletion is provided.
keywords
general
| keyword |
description |
| nop |
no operation |
| help |
(or h or ?) this help message |
| quit |
(or q or exit) quit software |
| version |
show rpn version |
| uname |
show rpn complete identification string |
| type |
show type of stack first entry |
| default |
set float representation and precision to default |
| prec |
get float precision in bits when first stack is not a number, set float precision in bits when first stack entry is a number. ex: 256 prec |
| round |
set float rounding mode. Authoerized values are: ["nearest", "toward zero", "toward +inf", "toward -inf", "away from zero"] round. ex: "nearest" round |
real
| keyword |
description |
| + |
addition |
| - |
substraction |
| neg |
negation |
| * |
multiplication |
| / |
division |
| inv |
inverse |
| % |
purcent |
| % |
CH inverse purcent |
| ^ |
(or pow) power |
| sqrt |
square root |
| sq |
(or sqr) square |
| mod |
modulo |
| abs |
absolute value |
real representation
| keyword |
description |
| dec |
decimal representation |
| hex |
hexadecimal representation |
| bin |
binary representation |
| std |
standard floating numbers representation. ex: [25] std |
| fix |
fixed point representation. ex: 6 fix |
| sci |
scientific floating point representation. ex: 20 sci |
test
| keyword |
description |
| > |
binary operator > |
| >= |
binary operator >= |
| < |
binary operator < |
| <= |
binary operator <= |
| != |
binary operator != (different) |
| == |
binary operator == (equal) |
| and |
boolean operator and |
| or |
boolean operator or |
| xor |
boolean operator xor |
| not |
boolean operator not |
| same |
boolean operator same (equal) |
stack
| keyword |
description |
| swap |
swap 2 first stack entries |
| drop |
drop first stack entry |
| drop2 |
drop 2 first stack entries |
| dropn |
drop n first stack entries |
| erase |
drop all stack entries |
| rot |
rotate 3 first stack entries |
| dup |
duplicate first stack entry |
| dup2 |
duplicate 2 first stack entries |
| dupn |
duplicate n first stack entries |
| pick |
push a copy of the given stack level onto the stack |
| depth |
give stack depth |
| roll |
move a stack entry to the top of the stack |
| rolld |
move the element on top of the stack to a higher stack position |
| over |
push a copy of the element in stack level 2 onto the stack |
string
| keyword |
description |
| ->str |
convert an object into a string |
| str-> |
convert a string into an object |
branch
| keyword |
description |
| if |
test-instructions |
| then |
true-instructions |
| else |
false-instructions |
| end |
(end of if structure) |
| start |
repeat instructions several times |
| for |
repeat instructions several times with variable |
| next |
ex: 1 10 start <instructions> next |
| step |
ex: 1 100 start <instructions> 4 step |
store
| keyword |
description |
| sto |
store a variable. ex: 1 'name' sto |
| rcl |
recall a variable. ex: 'name' rcl |
| purge |
delete a variable. ex: 'name' purge |
| vars |
list all variables |
| edit |
edit a variable content |
program
| keyword |
description |
| eval |
evaluate (run) a program, or recall a variable. ex: 'my_prog' eval |
| -> |
load program local variables. ex: << -> n m << 0 n m for i i + next >> >> |
trig
| keyword |
description |
| pi |
pi constant |
| sin |
sinus |
| asin |
arg sinus |
| cos |
cosinus |
| acos |
arg cosinus |
| tan |
tangent |
| atan |
arg tangent |
| d |
->r convert degrees to radians |
| r |
->d convert radians to degrees |
logs
| keyword |
description |
| e |
exp(1) constant |
| log |
logarithm base 10 |
| alog |
(or exp10) exponential base 10 |
| log2 |
logarithm base 2 |
| alog2 |
(or exp2) exponential base 2 |
| ln |
logarithm base e |
| exp |
exponential |
| sinh |
hyperbolic sine |
| asinh |
inverse hyperbolic sine |
| cosh |
hyperbolic cosine |
| acosh |
inverse hyperbolic cosine |
| tanh |
hyperbolic tangent |
| atanh |
inverse hyperbolic tangent |
default
Default float mode is 'std' with 20 digits
Default floating point precision is 128 bits
Default rounding mode is 'nearest'
Tests
Unit tests are given as txt files in the test subdirectory.
Use the command 'test' to run a test file, eg
# cd src_directory/
# rpn
rpn> "test/01-all.txt"
rpn> test
## ENTRY TEST
(...)
# real decimal PASSED
# real hex PASSED
# real binary PASSED
(...)
Test output is done on stdout and is not stacked in rpn.
generation and installation
