Resistance calculator
Resistance calculator is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.
- Introduction
- Calculate the resistance of a network of resistors.
- The resistors can be connected in series or parallel.
- Use infix or RPN to state the network.
- Calculate resistance, voltage, current and power for every resistor and operation.
- Background
- Serial Resistors: the sum of the resistors gives the equivalent resistor
- Parallel Resistors: the inverse of the sum of the inverse of the resistors
- The voltage drops over the resistors
- Current = Resistance / Voltage
- Power = Current * Voltage
- Input
- Infix: ((((10 + 2) * 6 + 8) * 6 + 4) * 8 + 4) * 8 + 6
- RPN: 10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +
- Voltage = 18.0 V
- Output
- 10.000 ohms in the upper left corner is the equivalent resistance.
- The first operation is 10 + 2 = 12 which can be found in the three middle rows.
Ohm Volt Ampere Watt Network tree 10.000 18.000 1.800 32.400 + 4.000 7.200 1.800 12.960 | * 8.000 7.200 0.900 6.480 | | + 4.000 3.600 0.900 3.240 | | | * 8.000 3.600 0.450 1.620 | | | | + 4.000 1.800 0.450 0.810 | | | | | * 12.000 1.800 0.150 0.270 | | | | | | + 4.000 0.600 0.150 0.090 | | | | | | | * 12.000 0.600 0.050 0.030 | | | | | | | | + 10.000 0.500 0.050 0.025 | | | | | | | | | r 2.000 0.100 0.050 0.005 | | | | | | | | | r 6.000 0.600 0.100 0.060 | | | | | | | | r 8.000 1.200 0.150 0.180 | | | | | | | r 6.000 1.800 0.300 0.540 | | | | | | r 4.000 1.800 0.450 0.810 | | | | | r 8.000 3.600 0.450 1.620 | | | | r 4.000 3.600 0.900 3.240 | | | r 8.000 7.200 0.900 6.480 | | r 6.000 10.800 1.800 19.440 | r
11l
RPN
T Resistor
Float resistance
voltage = 0.0
Resistor? a, b
Char symbol
F (resistance = 0.0, Resistor? a = N, b = N; symbol = Char(‘r’))
.resistance = resistance
.a = a
.b = b
.symbol = symbol
F.virtual.new res() -> Float
R .resistance
F.virtual.new setVoltage(Float voltage) -> N
.voltage = voltage
F current()
R .voltage / .res()
F effect()
R .current() * .voltage
F report(level = ‘’) -> N
print(‘#4.3 #4.3 #4.3 #4.3 #.#.’.format(.res(), .voltage, .current(), .effect(), level, .symbol))
I .a != N {.a.report(level‘| ’)}
I .b != N {.b.report(level‘| ’)}
T Serial(Resistor)
F (Resistor a, b)
.a = move(b)
.b = a
.symbol = Char(‘+’)
F.virtual.override res() -> Float
R .a.res() + .b.res()
F.virtual.override setVoltage(Float voltage) -> N
V ra = .a.res()
V rb = .b.res()
.a.setVoltage(ra / (ra + rb) * voltage)
.b.setVoltage(rb / (ra + rb) * voltage)
.voltage = voltage
T Parallel(Resistor)
F (Resistor a, b)
.a = move(b)
.b = a
.symbol = Char(‘*’)
F.virtual.override res() -> Float
R 1 / (1 / .a.res() + 1 / .b.res())
F.virtual.override setVoltage(Float voltage) -> N
.a.setVoltage(voltage)
.b.setVoltage(voltage)
.voltage = voltage
F build(s)
[Resistor] stack
L(word) s.split(‘ ’)
I word == ‘+’
Resistor p = stack.pop()
stack.append(Serial(p, stack.pop()))
E I word == ‘*’
Resistor p = stack.pop()
stack.append(Parallel(p, stack.pop()))
E
stack.append(Resistor(Float(word)))
R stack.pop()
Resistor node = build(‘10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +’)
print(‘ Ohm Volt Ampere Watt Network tree’)
node.setVoltage(18.0)
node.report()
CoffeeScript
RPN
nd = (num) -> num.toFixed(3).padStart 8
class Resistor
constructor : (@resistance,@a=null,@b=null,@symbol='r') ->
res : -> @resistance
setVoltage : (@voltage) ->
current : -> @voltage / @res()
effect : -> @current() * @voltage
report : (level) ->
print "#{nd @res()} #{nd @voltage} #{nd @current()} #{nd @effect()} #{level}#{@symbol}"
if @a then @a.report level + "| "
if @b then @b.report level + "| "
class Serial extends Resistor
constructor : (a,b) -> super 0,a,b,'+'
res : -> @a.res() + @b.res()
setVoltage : (@voltage) ->
ra = @a.res()
rb = @b.res()
@a.setVoltage ra/(ra+rb) * @voltage
@b.setVoltage rb/(ra+rb) * @voltage
class Parallel extends Resistor
constructor : (a,b) -> super 0,a,b,'*'
res : -> 1 / (1 / @a.res() + 1 / @b.res())
setVoltage : (@voltage) ->
@a.setVoltage @voltage
@b.setVoltage @voltage
build = (s) ->
stack = []
for word in s.split ' '
if word == '+' then stack.push new Serial stack.pop(), stack.pop()
else if word == '*' then stack.push new Parallel stack.pop(), stack.pop()
else stack.push new Resistor parseFloat word
stack.pop()
node = build "10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +"
node.setVoltage 18.0
print " Ohm Volt Ampere Watt Network tree"
node.report ""
Go
Infix
package main
import "fmt"
type Resistor struct {
symbol rune
resistance, voltage float64
a, b *Resistor
}
func (r *Resistor) res() float64 {
switch r.symbol {
case '+':
return r.a.res() + r.b.res()
case '*':
return 1 / (1/r.a.res() + 1/r.b.res())
default:
return r.resistance
}
}
func (r *Resistor) setVoltage(voltage float64) {
switch r.symbol {
case '+':
ra := r.a.res()
rb := r.b.res()
r.a.setVoltage(ra / (ra + rb) * voltage)
r.b.setVoltage(rb / (ra + rb) * voltage)
case '*':
r.a.setVoltage(voltage)
r.b.setVoltage(voltage)
}
r.voltage = voltage
}
func (r *Resistor) current() float64 {
return r.voltage / r.res()
}
func (r *Resistor) effect() float64 {
return r.current() * r.voltage
}
func (r *Resistor) report(level string) {
fmt.Printf("%8.3f %8.3f %8.3f %8.3f %s%c\n", r.res(), r.voltage, r.current(), r.effect(), level, r.symbol)
if r.a != nil {
r.a.report(level + "| ")
}
if r.b != nil {
r.b.report(level + "| ")
}
}
func (r *Resistor) add(other *Resistor) *Resistor {
return &Resistor{'+', 0, 0, r, other}
}
func (r *Resistor) mul(other *Resistor) *Resistor {
return &Resistor{'*', 0, 0, r, other}
}
func main() {
var r [10]*Resistor
resistances := []float64{6, 8, 4, 8, 4, 6, 8, 10, 6, 2}
for i := 0; i < 10; i++ {
r[i] = &Resistor{'r', resistances[i], 0, nil, nil}
}
node := r[7].add(r[9]).mul(r[8]).add(r[6]).mul(r[5]).add(r[4]).mul(r[3]).add(r[2]).mul(r[1]).add(r[0])
node.setVoltage(18)
fmt.Println(" Ohm Volt Ampere Watt Network tree")
node.report("")
}
RPN
package main
import (
"fmt"
"strconv"
"strings"
)
type Stack []*Resistor
func (s *Stack) push(r *Resistor) {
*s = append(*s, r)
}
func (s *Stack) pop() *Resistor {
le := len(*s)
if le == 0 {
panic("Attempt to pop from an empty stack")
}
le--
r := (*s)[le]
*s = (*s)[:le]
return r
}
type Resistor struct {
symbol rune
resistance, voltage float64
a, b *Resistor
}
func (r *Resistor) res() float64 {
switch r.symbol {
case '+':
return r.a.res() + r.b.res()
case '*':
return 1 / (1/r.a.res() + 1/r.b.res())
default:
return r.resistance
}
}
func (r *Resistor) setVoltage(voltage float64) {
switch r.symbol {
case '+':
ra := r.a.res()
rb := r.b.res()
r.a.setVoltage(ra / (ra + rb) * voltage)
r.b.setVoltage(rb / (ra + rb) * voltage)
case '*':
r.a.setVoltage(voltage)
r.b.setVoltage(voltage)
}
r.voltage = voltage
}
func (r *Resistor) current() float64 {
return r.voltage / r.res()
}
func (r *Resistor) effect() float64 {
return r.current() * r.voltage
}
func (r *Resistor) report(level string) {
fmt.Printf("%8.3f %8.3f %8.3f %8.3f %s%c\n", r.res(), r.voltage, r.current(), r.effect(), level, r.symbol)
if r.a != nil {
r.a.report(level + "| ")
}
if r.b != nil {
r.b.report(level + "| ")
}
}
func build(rpn string) *Resistor {
st := new(Stack)
for _, token := range strings.Fields(rpn) {
switch token {
case "+":
b, a := st.pop(), st.pop()
st.push(&Resistor{'+', 0, 0, a, b})
case "*":
b, a := st.pop(), st.pop()
st.push(&Resistor{'*', 0, 0, a, b})
default:
r, _ := strconv.ParseFloat(token, 64)
st.push(&Resistor{'r', r, 0, nil, nil})
}
}
return st.pop()
}
func main() {
node := build("10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +")
node.setVoltage(18)
fmt.Println(" Ohm Volt Ampere Watt Network tree")
node.report("")
}
Julia
Infix
using Formatting
import Base.+, Base.*
mutable struct Resistor
operator::Char
voltage::Float64
resistance::Float64
a::Union{Resistor, Nothing}
b::Union{Resistor, Nothing}
end
function res(r::Resistor)
if r != nothing
if r.operator == '+'
return res(r.a) + res(r.b)
elseif r.operator == '*'
return 1 / ((1 / res(r.a)) + (1 / res(r.b)))
end
return r.resistance
end
end
function setvoltage(r, voltage)
if r != nothing
if r.operator == '+'
ra = res(r.a)
rb = res(r.b)
setvoltage(r.a, voltage * ra / (ra + rb))
setvoltage(r.b, voltage * rb / (ra + rb))
elseif r.operator == '*'
setvoltage(r.a, voltage)
setvoltage(r.b, voltage)
end
r.voltage = voltage
end
end
current(r) = r.voltage / res(r)
effect(r) = r.voltage * current(r)
function report(r, level=1)
nfmt(x::Real) = rpad(format(x, precision=3), 12)
afmt(arr::Vector) = join(map(nfmt, arr), "| ")
println(afmt([res(r), r.voltage, current(r), effect(r)]), "| "^level, r.operator)
if r.a != nothing
report(r.a, level + 1)
end
if r.b != nothing
report(r.b, level + 1)
end
end
Base.:+(a::Resistor, b::Resistor) = Resistor('+', 0.0, 0.0, a, b)
Base.:*(a::Resistor, b::Resistor) = Resistor('*', 0.0, 0.0, a, b)
(R1, R2, R3, R4, R5, R6, R7, R8, R9, R10) =
map(r -> Resistor('r', 0.0, r, nothing, nothing), [6, 8, 4, 8, 4, 6, 8, 10, 6, 2])
node = ((((R8 + R10) * R9 + R7) * R6 + R5) * R4 + R3) * R2 + R1
setvoltage(node, 18)
println(" Ohm Volt Ampere Watt Network tree")
report(node)
- Output:
Ohm Volt Ampere Watt Network tree 10.000 | 18.000 | 1.800 | 32.400 | + 4.000 | 7.200 | 1.800 | 12.960 | | * 8.000 | 7.200 | 0.900 | 6.480 | | | + 4.000 | 3.600 | 0.900 | 3.240 | | | | * 8.000 | 3.600 | 0.450 | 1.620 | | | | | + 4.000 | 1.800 | 0.450 | 0.810 | | | | | | * 12.000 | 1.800 | 0.150 | 0.270 | | | | | | | + 4.000 | 0.600 | 0.150 | 0.090 | | | | | | | | * 12.000 | 0.600 | 0.050 | 0.030 | | | | | | | | | + 10.000 | 0.500 | 0.050 | 0.025 | | | | | | | | | | r 2.000 | 0.100 | 0.050 | 0.005 | | | | | | | | | | r 6.000 | 0.600 | 0.100 | 0.060 | | | | | | | | | r 8.000 | 1.200 | 0.150 | 0.180 | | | | | | | | r 6.000 | 1.800 | 0.300 | 0.540 | | | | | | | r 4.000 | 1.800 | 0.450 | 0.810 | | | | | | r 8.000 | 3.600 | 0.450 | 1.620 | | | | | r 4.000 | 3.600 | 0.900 | 3.240 | | | | r 8.000 | 7.200 | 0.900 | 6.480 | | | r 6.000 | 10.800 | 1.800 | 19.440 | | r
RPN
function rpn(arr::Vector)
stack = Any[]
for op in arr
if isa(op, Function)
arg2 = pop!(stack)
arg1 = pop!(stack)
push!(stack, op(arg1, arg2))
else
push!(stack, op)
end
end
length(stack) != 1 && error("invalid RPN expression array: $arr")
return stack[1]
end
node = rpn([R8, R10, +, R9, *, R7, +, R6, *, R5, +, R4, *, R3, +, R2, *, R1, +])
setvoltage(node, 18)
report(node)
- Output:
Same as infix version.
Nim
import strutils, strformat
type
Node = ref object
kind: char # + = serial * = parallel r = resistor
resistance: float
voltage: float
a: Node
b: Node
proc res(node: Node): float =
if node.kind == '+': return node.a.res + node.b.res
if node.kind == '*': return 1 / (1 / node.a.res + 1 / node.b.res)
node.resistance
proc current(node: Node): float = node.voltage / node.res
proc effect (node: Node): float = node.current * node.voltage
proc report(node: Node, level: string = "") =
echo fmt"{node.res:8.3f} {node.voltage:8.3f} {node.current:8.3f} {node.effect:8.3f} {level}{node.kind}"
if node.kind in "+*":
node.a.report level & "| "
node.b.report level & "| "
proc setVoltage(node: Node, voltage: float) =
node.voltage = voltage
if node.kind == '+':
let ra = node.a.res
let rb = node.b.res
node.a.setVoltage ra / (ra+rb) * voltage
node.b.setVoltage rb / (ra+rb) * voltage
if node.kind == '*':
node.a.setVoltage voltage
node.b.setVoltage voltage
proc build(tokens: seq[string]): Node =
var stack: seq[Node]
for token in tokens:
stack.add if token == "+": Node(kind: '+', a: stack.pop, b: stack.pop)
elif token == "*": Node(kind: '*', a: stack.pop, b: stack.pop)
else: Node(kind: 'r', resistance: parseFloat(token))
stack.pop
proc calculate(voltage: float, tokens: seq[string]): Node =
echo ""
echo " Ohm Volt Ampere Watt Network tree"
let node = build tokens
node.setVoltage voltage
node.report
node
RPN
proc rpn(voltage:float, s:string): Node = calculate(voltage, s.split ' ')
var node = rpn(18, "10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +")
assert 10 == node.res
assert 18 == node.voltage
assert 1.8 == node.current()
assert 32.4 == node.effect()
assert '+' == node.kind
Infix
proc parse(s: string): seq[string] =
var tmp = ""
for ch in s:
case ch
of ' ':
if tmp != "": result.add tmp
tmp = ""
continue
of '+', '*', '(', ')':
if tmp != "": result.add tmp
tmp = ""
result.add $ch
else:
tmp &= ch
if tmp != "": result.add tmp
proc shuntRPN(s: string): seq[string] =
let ops = "+*"
var tokens = parse s
var stack: seq[string]
var op: string
for token in tokens:
case token
of "(":
stack.add token
of ")":
while stack.len > 0:
op = stack.pop()
if op == "(": break
result.add op
else:
if token in ops:
while stack.len > 0:
op = stack[^1]
if op notin ops: break
if ops.find(token) >= ops.find(op): break
discard stack.pop()
result.add op
stack.add token
else: result.add token
while stack.len > 0: result.add stack.pop()
proc infix(voltage:float, s:string): Node = calculate(voltage, shuntRPN s)
node = infix(18, "((((10+2)*6+8)*6+4)*8+4)*8+6")
assert 10 == node.res
assert 18 == node.voltage
assert 1.8 == node.current()
assert 32.4 == node.effect()
assert '+' == node.kind
Perl
Infix
use strict;
use warnings;
use feature <say state>;
{
package Resistor;
sub new {
my ($class, $args) = @_;
my $self = {
symbol => $args->{symbol},
voltage => $args->{voltage},
resistance => $args->{resistance},
a => $args->{a},
b => $args->{b},
};
return bless $self, $class;
}
sub res {
my $self = shift;
if ($self->{symbol} eq '+') { return res($self->{a}) + res($self->{b}) }
elsif ($self->{symbol} eq '*') { return 1 / (1/res($self->{a}) + 1/res($self->{b})) }
else { return $self->{resistance} }
}
sub set_voltage {
my($self,$voltage) = @_;
if ($self->{symbol} eq '+') {
my $ra = res($self->{a});
my $rb = res($self->{b});
set_voltage($self->{a}, $ra / ($ra+$rb) * $voltage );
set_voltage($self->{b}, $rb / ($ra+$rb) * $voltage );
} elsif ($self->{symbol} eq '*') {
set_voltage($self->{a}, $voltage );
set_voltage($self->{b}, $voltage );
}
$self->{voltage} = $voltage;
}
sub current { my $self = shift; return $self->{voltage} / res($self) }
sub effect { my $self = shift; return $self->{voltage} * current($self) }
use overload '+' => \&serial,
'*' => \∥
sub serial { my($a,$b) = @_; Resistor->new( {symbol => '+', a => $a, b => $b} ) }
sub parallel { my($a,$b) = @_; Resistor->new( {symbol => '*', a => $a, b => $b} ) }
sub report {
my($self,$level) = @_;
state @results;
push @results, ' Ohm Volt Ampere Watt Network tree' and $level = 1 unless $level;
my $pad = ('| ') x $level;
my $f = sprintf '%9.3f' x 4, res($self), $self->{voltage}, current($self), effect($self);
say "$f $pad" . $self->{symbol};
report($self->{a}, $level+1) if defined $self->{a};
report($self->{b}, $level+1) if defined $self->{b};
join "\n", @results;
}
}
package main;
my ($R1, $R2, $R3, $R4, $R5, $R6, $R7, $R8, $R9, $R10) =
map { Resistor->new( {symbol => 'r', resistance => $_} ) } <6 8 4 8 4 6 8 10 6 2>;
my $node = (((($R8 + $R10) * $R9 + $R7) * $R6 + $R5)
* $R4 + $R3) * $R2 + $R1;
Resistor::set_voltage($node,18);
say Resistor::report($node);
- Output:
Ohm Volt Ampere Watt Network tree 10.000 18.000 1.800 32.400 | + 4.000 7.200 1.800 12.960 | | * 8.000 7.200 0.900 6.480 | | | + 4.000 3.600 0.900 3.240 | | | | * 8.000 3.600 0.450 1.620 | | | | | + 4.000 1.800 0.450 0.810 | | | | | | * 12.000 1.800 0.150 0.270 | | | | | | | + 4.000 0.600 0.150 0.090 | | | | | | | | * 12.000 0.600 0.050 0.030 | | | | | | | | | + 10.000 0.500 0.050 0.025 | | | | | | | | | | r 2.000 0.100 0.050 0.005 | | | | | | | | | | r 6.000 0.600 0.100 0.060 | | | | | | | | | r 8.000 1.200 0.150 0.180 | | | | | | | | r 6.000 1.800 0.300 0.540 | | | | | | | r 4.000 1.800 0.450 0.810 | | | | | | r 8.000 3.600 0.450 1.620 | | | | | r 4.000 3.600 0.900 3.240 | | | | r 8.000 7.200 0.900 6.480 | | | r 6.000 10.800 1.800 19.440 | | r
Phix
with javascript_semantics constant RPN = true // or false for infix (same output) -- node contents: enum KIND, -- '+', '*', or 'r' RESISTANCE, VOLTAGE, A, B -- nested nodes or NULL function resistance(sequence node) switch node[KIND] do case '+': return resistance(node[A]) + resistance(node[B]) case '*': return 1 / (1/resistance(node[A]) + 1/resistance(node[B])) case 'r': return node[RESISTANCE] default: ?9/0 -- unknown node kind end switch end function function setVoltage(sequence node, atom voltage) integer kind = node[KIND] atom r = node[RESISTANCE] -- v = node[VOLTAGE] -- not needed! object na = node[A], nb = node[B] switch kind do case '+': atom ra := resistance(na), rb := resistance(nb) na = setVoltage(na, ra / (ra + rb) * voltage) nb = setVoltage(nb, rb / (ra + rb) * voltage) case '*': na = setVoltage(na,voltage) nb = setVoltage(nb,voltage) end switch node = {kind,r,voltage,na,nb} return node end function function current(sequence node) return node[VOLTAGE] / resistance(node) end function function effect(sequence node) return current(node) * node[VOLTAGE] end function procedure report(sequence node, string level="") printf(1,"%8.3f %8.3f %8.3f %8.3f %s%c\n", {resistance(node), node[VOLTAGE], current(node), effect(node), level, node[KIND]}) if node[A]!=NULL then report(node[A],level & "| ") end if if node[B]!=NULL then report(node[B],level & "| ") end if end procedure function push_op(sequence stack, string tok) switch tok do case "+","*": sequence b = stack[$], a = stack[$-1] stack = stack[1..$-1] stack[$] = {tok[1], 0, 0, a, b} default: integer {{r}} = scanf(tok,"%d") stack = append(stack,{'r', r, 0, NULL, NULL}) end switch return stack end function -- RPN function rpn(string s) sequence stack = {}, tokens = split(s) for i=1 to length(tokens) do stack = push_op(stack,tokens[i]) end for return stack[$] end function -- Infix, slightly trickier: constant ops = {"+","*"} function infix(string s) string lastnum = "" sequence tokens = {} for i=1 to length(s) do integer ch = s[i] if ch>='0' and ch<='9' then lastnum &= ch else if length(lastnum) then tokens = append(tokens,lastnum) lastnum = "" end if tokens = append(tokens,ch&"") end if end for if length(lastnum) then tokens = append(tokens,lastnum) end if sequence stack = {}, result = {} for i=1 to length(tokens) do string token = tokens[i], op switch token do case "(": stack = append(stack,token) case ")": while true do op = stack[$] stack = stack[1..$-1] if op == "(" then exit end if result = push_op(result,op) end while else: integer tp = find(token,ops) if tp then while length(stack) do op = stack[$] integer sp = find(op,ops) if not sp or tp>=sp then exit end if stack = stack[1..$-1] result = push_op(result,op) end while stack = append(stack,token) else result = push_op(result,token) end if end switch end for for i=length(stack) to 1 by -1 do result = push_op(result,stack[i]) end for return result[1] end function sequence node = iff(RPN?rpn("10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +") :infix("((((10+2)*6+8)*6+4)*8+4)*8+6")) node = setVoltage(node,18) printf(1," Ohm Volt Ampere Watt Network tree\n") report(node,"")
- Output:
Ohm Volt Ampere Watt Network tree 10.000 18.000 1.800 32.400 + 4.000 7.200 1.800 12.960 | * 8.000 7.200 0.900 6.480 | | + 4.000 3.600 0.900 3.240 | | | * 8.000 3.600 0.450 1.620 | | | | + 4.000 1.800 0.450 0.810 | | | | | * 12.000 1.800 0.150 0.270 | | | | | | + 4.000 0.600 0.150 0.090 | | | | | | | * 12.000 0.600 0.050 0.030 | | | | | | | | + 10.000 0.500 0.050 0.025 | | | | | | | | | r 2.000 0.100 0.050 0.005 | | | | | | | | | r 6.000 0.600 0.100 0.060 | | | | | | | | r 8.000 1.200 0.150 0.180 | | | | | | | r 6.000 1.800 0.300 0.540 | | | | | | r 4.000 1.800 0.450 0.810 | | | | | r 8.000 3.600 0.450 1.620 | | | | r 4.000 3.600 0.900 3.240 | | | r 8.000 7.200 0.900 6.480 | | r 6.000 10.800 1.800 19.440 | r
Python
RPN
class Resistor :
def __init__(self, resistance, a=None, b=None, symbol='r'):
self.resistance = resistance
self.a = a
self.b = b
self.symbol = symbol
def res(self) : return self.resistance
def setVoltage(self, voltage): self.voltage = voltage
def current(self) : return self.voltage / self.res()
def effect(self) : return self.current() * self.voltage
def report(self,level=""):
print(f"{self.res():8.3f} {self.voltage:8.3f} {self.current():8.3f} {self.effect():8.3f} {level}{self.symbol}")
if self.a: self.a.report(level + "| ")
if self.b: self.b.report(level + "| ")
class Serial(Resistor) :
def __init__(self, a, b) : super().__init__(0, b, a, '+')
def res(self) : return self.a.res() + self.b.res()
def setVoltage(self, voltage) :
ra = self.a.res()
rb = self.b.res()
self.a.setVoltage(ra/(ra+rb) * voltage)
self.b.setVoltage(rb/(ra+rb) * voltage)
self.voltage = voltage
class Parallel(Resistor) :
def __init__(self,a,b) : super().__init__(0, b, a, '*')
def res(self) : return 1 / (1 / self.a.res() + 1 / self.b.res())
def setVoltage(self, voltage) :
self.a.setVoltage(voltage)
self.b.setVoltage(voltage)
self.voltage = voltage
def build(s) :
stack = []
for word in s.split(' '):
if word == "+": stack.append(Serial(stack.pop(), stack.pop()))
elif word == "*": stack.append(Parallel(stack.pop(), stack.pop()))
else: stack.append(Resistor(float(word)))
return stack.pop()
node = build("10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +")
print(" Ohm Volt Ampere Watt Network tree")
node.setVoltage(18.0)
node.report()
Infix
class Resistor :
def __init__(self, resistance, a=None, b=None, symbol='r') :
self.resistance = resistance
self.a = a
self.b = b
self.symbol = symbol
def res(self) : return self.resistance
def setVoltage(self, voltage) : self.voltage = voltage
def current(self) : return self.voltage / self.res()
def effect(self) : return self.current() * self.voltage
def report(self,level="") :
print(f"{self.res():8.3f} {self.voltage:8.3f} {self.current():8.3f} {self.effect():8.3f} {level}{self.symbol}")
if self.a: self.a.report(level + "| ")
if self.b: self.b.report(level + "| ")
def __add__(self,other) : return Serial(self,other)
def __mul__(self,other) : return Parallel(self,other)
class Serial(Resistor) :
def __init__(self, a, b) : super().__init__(0, a, b, '+')
def res(self) : return self.a.res() + self.b.res()
def setVoltage(self, voltage) :
ra = self.a.res()
rb = self.b.res()
self.a.setVoltage(ra/(ra+rb) * voltage)
self.b.setVoltage(rb/(ra+rb) * voltage)
self.voltage = voltage
class Parallel(Resistor) :
def __init__(self,a,b) : super().__init__(0, a, b, '*')
def res(self) : return 1 / (1 / self.a.res() + 1 / self.b.res())
def setVoltage(self, voltage):
self.a.setVoltage(voltage)
self.b.setVoltage(voltage)
self.voltage = voltage
[R1,R2,R3,R4,R5,R6,R7,R8,R9,R10] = [Resistor(res) for res in [6,8,4,8,4,6,8,10,6,2]]
node = ((((R8+R10) * R9 + R7) * R6 + R5) * R4 + R3) * R2 + R1
node.setVoltage(18)
print(" Ohm Volt Ampere Watt Network tree")
node.report()
Raku
(formerly Perl 6)
Infix
class Resistor {
has Str $.symbol;
has Numeric ( $.voltage, $.resistance );
has Resistor ( $.a, $.b );
method res ( ) {
given $.symbol {
when '+' { return $.a.res + $.b.res }
when '*' { return 1 / (1 / $.a.res + 1 / $.b.res) }
default { return $.resistance }
}
}
method set-voltage ( Numeric $voltage ) {
given $.symbol {
when '+' {
my $ra = $.a.res;
my $rb = $.b.res;
$.a.set-voltage( $ra / ($ra+$rb) * $voltage );
$.b.set-voltage( $rb / ($ra+$rb) * $voltage );
}
when '*' {
$.a.set-voltage( $voltage );
$.b.set-voltage( $voltage );
}
}
$!voltage = $voltage;
}
method current ( ) { return $.voltage / self.res }
method effect ( ) { return $.voltage * self.current }
method report ( Int $level = 1 ) {
my $pad = '| ' x $level;
my $f = ( self.res, $.voltage, self.current, self.effect ).fmt('%8.3f');
say "$f $pad$.symbol";
$.a.report( $level+1 ) if $.a;
$.b.report( $level+1 ) if $.b;
}
}
multi sub infix:<+> (Resistor $a, Resistor $b) { $a.new( symbol => '+', :$a, :$b ) }
multi sub infix:<*> (Resistor $a, Resistor $b) { $a.new( symbol => '*', :$a, :$b ) }
my Resistor ($R1, $R2, $R3, $R4, $R5, $R6, $R7, $R8, $R9, $R10) =
map { Resistor.new: symbol => 'r', resistance => $_ },
6, 8, 4, 8, 4, 6, 8, 10, 6, 2;
my $node = (((($R8 + $R10) * $R9 + $R7) * $R6 + $R5)
* $R4 + $R3) * $R2 + $R1;
$node.set-voltage(18);
say ' Ohm Volt Ampere Watt Network tree';
$node.report;
- Output:
Ohm Volt Ampere Watt Network tree 10.000 18.000 1.800 32.400 | + 4.000 7.200 1.800 12.960 | | * 8.000 7.200 0.900 6.480 | | | + 4.000 3.600 0.900 3.240 | | | | * 8.000 3.600 0.450 1.620 | | | | | + 4.000 1.800 0.450 0.810 | | | | | | * 12.000 1.800 0.150 0.270 | | | | | | | + 4.000 0.600 0.150 0.090 | | | | | | | | * 12.000 0.600 0.050 0.030 | | | | | | | | | + 10.000 0.500 0.050 0.025 | | | | | | | | | | r 2.000 0.100 0.050 0.005 | | | | | | | | | | r 6.000 0.600 0.100 0.060 | | | | | | | | | r 8.000 1.200 0.150 0.180 | | | | | | | | r 6.000 1.800 0.300 0.540 | | | | | | | r 4.000 1.800 0.450 0.810 | | | | | | r 8.000 3.600 0.450 1.620 | | | | | r 4.000 3.600 0.900 3.240 | | | | r 8.000 7.200 0.900 6.480 | | | r 6.000 10.800 1.800 19.440 | | r
Wren
Infix
import "/fmt" for Fmt
class Resistor {
construct new(symbol, resistance, voltage, a, b) {
_symbol = symbol
_resistance = resistance
_voltage = voltage
_a = a
_b = b
}
symbol { _symbol }
resistance { _resistance }
voltage { _voltage}
res {
if (_symbol == "+") return _a.res + _b.res
if (_symbol == "*") return 1 / (1/_a.res + 1/_b.res)
return _resistance
}
current { _voltage / res }
effect { current * _voltage }
voltage=(v) {
if (_symbol == "+") {
var ra = _a.res
var rb = _b.res
_a.voltage = ra / (ra + rb) * v
_b.voltage = rb / (ra + rb) * v
} else if (_symbol == "*") {
_a.voltage = v
_b.voltage = v
}
_voltage = v
}
report(level) {
Fmt.lprint("$8.3f $8.3f $8.3f $8.3f $s$s", [res, _voltage, current, effect, level, symbol])
if (_a != null) _a.report(level + "| ")
if (_b != null) _b.report(level + "| ")
}
+(other) { Resistor.new("+", 0, 0, this, other) }
*(other) { Resistor.new("*", 0, 0, this, other) }
}
var r = List.filled(10, null)
var resistances = [6, 8, 4, 8, 4, 6, 8, 10, 6, 2]
for (i in 0..9) r[i] = Resistor.new("r", resistances[i], 0, null, null)
var node = ((((r[7]+r[9])*r[8]+r[6])*r[5]+r[4])*r[3]+r[2])*r[1] + r[0]
node.voltage = 18
System.print(" Ohm Volt Ampere Watt Network tree")
node.report("")
- Output:
Ohm Volt Ampere Watt Network tree 10.000 18.000 1.800 32.400 + 4.000 7.200 1.800 12.960 | * 8.000 7.200 0.900 6.480 | | + 4.000 3.600 0.900 3.240 | | | * 8.000 3.600 0.450 1.620 | | | | + 4.000 1.800 0.450 0.810 | | | | | * 12.000 1.800 0.150 0.270 | | | | | | + 4.000 0.600 0.150 0.090 | | | | | | | * 12.000 0.600 0.050 0.030 | | | | | | | | + 10.000 0.500 0.050 0.025 | | | | | | | | | r 2.000 0.100 0.050 0.005 | | | | | | | | | r 6.000 0.600 0.100 0.060 | | | | | | | | r 8.000 1.200 0.150 0.180 | | | | | | | r 6.000 1.800 0.300 0.540 | | | | | | r 4.000 1.800 0.450 0.810 | | | | | r 8.000 3.600 0.450 1.620 | | | | r 4.000 3.600 0.900 3.240 | | | r 8.000 7.200 0.900 6.480 | | r 6.000 10.800 1.800 19.440 | r
RPN
Additonally:
import "/fmt" for Fmt
import "/seq" for Stack
class Resistor {
construct new(symbol, resistance, voltage, a, b) {
_symbol = symbol
_resistance = resistance
_voltage = voltage
_a = a
_b = b
}
symbol { _symbol }
resistance { _resistance }
voltage { _voltage}
res {
if (_symbol == "+") return _a.res + _b.res
if (_symbol == "*") return 1 / (1/_a.res + 1/_b.res)
return _resistance
}
current { _voltage / res }
effect { current * _voltage }
voltage=(v) {
if (_symbol == "+") {
var ra = _a.res
var rb = _b.res
_a.voltage = ra / (ra + rb) * v
_b.voltage = rb / (ra + rb) * v
} else if (_symbol == "*") {
_a.voltage = v
_b.voltage = v
}
_voltage = v
}
report(level) {
Fmt.lprint("$8.3f $8.3f $8.3f $8.3f $s$s", [res, _voltage, current, effect, level, symbol])
if (_a != null) _a.report(level + "| ")
if (_b != null) _b.report(level + "| ")
}
+(other) { Resistor.new("+", 0, 0, this, other) }
*(other) { Resistor.new("*", 0, 0, this, other) }
}
var build = Fn.new { |rpn|
var st = Stack.new()
for (token in rpn.split(" ")) {
if (token == "+") {
var b = st.pop()
var a = st.pop()
st.push(Resistor.new("+", 0, 0, a, b))
} else if (token == "*") {
var b = st.pop()
var a = st.pop()
st.push(Resistor.new("*", 0, 0, a, b))
} else {
var r = Num.fromString(token)
st.push(Resistor.new("r", r, 0, null, null))
}
}
return st.pop()
}
var node = build.call("10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +")
node.voltage = 18
System.print(" Ohm Volt Ampere Watt Network tree")
node.report("")
- Output:
Same as Infix version
zkl
class Resistor{
fcn init(resistance_,symbol_="r", a_=Void, b_=Void){
var resistance,a,b,symbol, voltage=Void;
resistance,symbol,a,b = vm.arglist;
resistance=resistance.toFloat(); // deal with strings/ints
}
fcn res{
if (symbol=="+") a.res() + b.res();
else if(symbol=="*") 1.0/(1.0/a.res() + 1.0/b.res());
else resistance
}
fcn setVoltage(voltage){
if(symbol=="+"){
ra,rb := a.res(), b.res();
a.setVoltage(ra/(ra + rb)*voltage);
b.setVoltage(rb/(ra + rb)*voltage);
}
else if(symbol=="*") T(a,b).apply2("setVoltage",voltage);
self.voltage = voltage.toFloat();
}
fcn current{ voltage/res() }
fcn effect { current()*voltage }
fcn report(level=""){
println("%8.3f %8.3f %8.3f %8.3f %s%s".fmt(res(),voltage,current(),effect(),level,symbol));
T(a,b).apply2("report",level + "| "); // noop if Void
}
fcn __opAdd(other){ Resistor(0,"+",self,other) }
fcn __opMul(other){ Resistor(0,"*",self,other) }
}
Infix
R1,R2,R3,R4,R5,R6,R7,R8,R9,R10 := T(6,8,4,8,4,6,8,10,6,2].apply(Resistor);
node:=((((R8 + R10)*R9 + R7)*R6 + R5)*R4 + R3)*R2 + R1;
node.setVoltage(18);
println(" Ohm Volt Ampere Watt Network tree");
node.report();
- Output:
Ohm Volt Ampere Watt Network tree 10.000 18.000 1.800 32.400 + 4.000 7.200 1.800 12.960 | * 8.000 7.200 0.900 6.480 | | + 4.000 3.600 0.900 3.240 | | | * 8.000 3.600 0.450 1.620 | | | | + 4.000 1.800 0.450 0.810 | | | | | * 12.000 1.800 0.150 0.270 | | | | | | + 4.000 0.600 0.150 0.090 | | | | | | | * 12.000 0.600 0.050 0.030 | | | | | | | | + 10.000 0.500 0.050 0.025 | | | | | | | | | r 2.000 0.100 0.050 0.005 | | | | | | | | | r 6.000 0.600 0.100 0.060 | | | | | | | | r 8.000 1.200 0.150 0.180 | | | | | | | r 6.000 1.800 0.300 0.540 | | | | | | r 4.000 1.800 0.450 0.810 | | | | | r 8.000 3.600 0.450 1.620 | | | | r 4.000 3.600 0.900 3.240 | | | r 8.000 7.200 0.900 6.480 | | r 6.000 10.800 1.800 19.440 | r
RPN
fcn build(rpnStr){
stack:=List();
foreach symbol in (rpnStr.split()){
if(symbol=="+"){
a,b:=stack.pop(),stack.pop();
stack.append(Resistor(0,"+",b,a))
}
else if(symbol=="*"){
a,b:=stack.pop(),stack.pop();
stack.append(Resistor(0,"*",b,a))
}
else stack.append(Resistor(symbol,"r"));
}
stack.pop() // unevaluated top of circuit
}
node:=build("10 2 + 6 * 8 + 6 * 4 + 8 * 4 + 8 * 6 +");
node.setVoltage(18);
println(" Ohm Volt Ampere Watt Network tree");
node.report();
- Output:
Ohm Volt Ampere Watt Network tree 10.000 18.000 1.800 32.400 + 4.000 7.200 1.800 12.960 | * 8.000 7.200 0.900 6.480 | | + 4.000 3.600 0.900 3.240 | | | * 8.000 3.600 0.450 1.620 | | | | + 4.000 1.800 0.450 0.810 | | | | | * 12.000 1.800 0.150 0.270 | | | | | | + 4.000 0.600 0.150 0.090 | | | | | | | * 12.000 0.600 0.050 0.030 | | | | | | | | + 10.000 0.500 0.050 0.025 | | | | | | | | | r 2.000 0.100 0.050 0.005 | | | | | | | | | r 6.000 0.600 0.100 0.060 | | | | | | | | r 8.000 1.200 0.150 0.180 | | | | | | | r 6.000 1.800 0.300 0.540 | | | | | | r 4.000 1.800 0.450 0.810 | | | | | r 8.000 3.600 0.450 1.620 | | | | r 4.000 3.600 0.900 3.240 | | | r 8.000 7.200 0.900 6.480 | | r 6.000 10.800 1.800 19.440 | r