commit 501f66abb6c64070d3d53ba7b4a2f9dcbb683109
parent 2924f174a6f1d3510a52b1f86d211cb306d2150a
Author: NunoSempere <nuno.semperelh@protonmail.com>
Date: Wed, 19 Jun 2024 09:55:56 -0400
add simplified version of repl
Diffstat:
| A | f_simple.go | | | 372 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
1 file changed, 372 insertions(+), 0 deletions(-)
diff --git a/f_simple.go b/f_simple.go
@@ -0,0 +1,372 @@
+package main
+
+import (
+ "bufio"
+ "errors"
+ "fmt"
+ "git.nunosempere.com/NunoSempere/fermi/pretty"
+ "git.nunosempere.com/NunoSempere/fermi/sample"
+ "math"
+ "os"
+ "sort"
+ "strconv"
+ "strings"
+)
+
+/* Types and interfaces */
+
+type Dist interface {
+ Samples() []float64
+}
+
+type Scalar float64
+
+type Lognormal struct {
+ low float64
+ high float64
+}
+
+type Beta struct {
+ a float64
+ b float64
+}
+
+type FilledSamples struct {
+ xs []float64
+}
+
+/* Dist interface functions */
+// https://go.dev/tour/methods/9
+func (p Scalar) Samples() []float64 {
+ xs := make([]float64, N_SAMPLES)
+ for i := 0; i < N_SAMPLES; i++ {
+ xs[i] = float64(p)
+ }
+ return xs
+}
+
+func (ln Lognormal) Samples() []float64 {
+ sampler := func(r sample.Src) float64 { return sample.Sample_to(ln.low, ln.high, r) }
+ return sample.Sample_serially(sampler, N_SAMPLES)
+}
+
+func (beta Beta) Samples() []float64 {
+ sampler := func(r sample.Src) float64 { return sample.Sample_beta(beta.a, beta.b, r) }
+ return sample.Sample_serially(sampler, N_SAMPLES)
+}
+
+func (fs FilledSamples) Samples() []float64 {
+ return fs.xs
+}
+
+/* Constants */
+const HELP_MSG = " Operation | Variable assignment | Special\n" +
+ " Operation: operator operand\n" +
+ " operator: (empty) | * | / | + | -\n" +
+ " operand: scalar | lognormal | beta | variable\n" +
+ " lognormal: low high\n" +
+ " beta: beta alpha beta\n" +
+ " Clear stack: . | c | clear\n" +
+ " Other special operations: help | debug | exit\n" +
+ " Examples: \n" +
+ " + 2\n" +
+ " / 2.5\n" +
+ " * 1 10 (interpreted as lognormal)\n" +
+ " + 1 10\n" +
+ " * beta 1 10\n" +
+ " 1 10 (multiplication taken as default operation)\n" +
+ " .\n" +
+ " 1 100\n" +
+ " exit\n"
+const NORMAL90CONFIDENCE = 1.6448536269514727
+const INIT_DIST Scalar = Scalar(1)
+const N_SAMPLES = 100_000
+
+/* Printers */
+func prettyPrintDist(dist Dist) {
+ switch v := dist.(type) {
+ case Lognormal:
+ fmt.Printf("=> ")
+ pretty.PrettyPrint2Floats(v.low, v.high)
+ fmt.Println()
+ case Beta:
+ fmt.Printf("=> beta ")
+ pretty.PrettyPrint2Floats(v.a, v.b)
+ fmt.Println()
+ case Scalar:
+ fmt.Printf("=> scalar ")
+ w := float64(v)
+ pretty.PrettyPrintFloat(w)
+ fmt.Println()
+ case FilledSamples:
+ sorted_xs := make([]float64, N_SAMPLES)
+ copy(sorted_xs, v.xs)
+ sort.Slice(sorted_xs, func(i, j int) bool {
+ return sorted_xs[i] < sorted_xs[j]
+ })
+
+ low := sorted_xs[N_SAMPLES/20]
+ high := sorted_xs[N_SAMPLES*19/20]
+ fmt.Printf("=> ")
+ pretty.PrettyPrint2Floats(low, high)
+
+ fmt.Printf(" (")
+ pretty.PrettyPrintInt(N_SAMPLES)
+ fmt.Printf(" samples)")
+ fmt.Println()
+ default:
+ fmt.Printf("%v\n", v)
+ }
+}
+
+func printAndReturnErr(err_msg string) error {
+ fmt.Println(err_msg)
+ fmt.Println(HELP_MSG)
+ return errors.New(err_msg)
+}
+
+/* Operations */
+// Generic operations with samples
+func operateDistsAsSamples(dist1 Dist, dist2 Dist, op string) (Dist, error) {
+
+ xs := dist1.Samples()
+ ys := dist2.Samples()
+ zs := make([]float64, N_SAMPLES)
+
+ for i := 0; i < N_SAMPLES; i++ {
+ switch op {
+ case "*":
+ zs[i] = xs[i] * ys[i]
+ case "/":
+ if ys[0] != 0 {
+ zs[i] = xs[i] / ys[i]
+ } else {
+ fmt.Println("Error: When dividing as samples, division by zero")
+ return nil, errors.New("Division by zero")
+ }
+ case "+":
+ zs[i] = xs[i] + ys[i]
+ case "-":
+ zs[i] = xs[i] - ys[i]
+ }
+ }
+
+ // fmt.Printf("%v\n", zs)
+ return FilledSamples{xs: zs}, nil
+}
+
+// Multiplication
+func multiplyLogDists(l1 Lognormal, l2 Lognormal) Lognormal {
+ logmean1 := (math.Log(l1.high) + math.Log(l1.low)) / 2.0
+ logstd1 := (math.Log(l1.high) - math.Log(l1.low)) / (2.0 * NORMAL90CONFIDENCE)
+
+ logmean2 := (math.Log(l2.high) + math.Log(l2.low)) / 2.0
+ logstd2 := (math.Log(l2.high) - math.Log(l2.low)) / (2.0 * NORMAL90CONFIDENCE)
+
+ logmean_product := logmean1 + logmean2
+ logstd_product := math.Sqrt(logstd1*logstd1 + logstd2*logstd2)
+
+ h := logstd_product * NORMAL90CONFIDENCE
+ loglow := logmean_product - h
+ loghigh := logmean_product + h
+ return Lognormal{low: math.Exp(loglow), high: math.Exp(loghigh)}
+
+}
+
+func multiplyBetaDists(beta1 Beta, beta2 Beta) Beta {
+ return Beta{a: beta1.a + beta2.a, b: beta1.b + beta2.b}
+}
+
+func multiplyDists(old_dist Dist, new_dist Dist) (Dist, error) {
+
+ switch o := old_dist.(type) {
+ case Lognormal:
+ {
+ switch n := new_dist.(type) {
+ case Lognormal:
+ return multiplyLogDists(o, n), nil
+ case Scalar:
+ return multiplyLogDists(o, Lognormal{low: float64(n), high: float64(n)}), nil
+ default:
+ return operateDistsAsSamples(old_dist, new_dist, "*")
+ }
+ }
+ case Scalar:
+ {
+ if o == 1 {
+ return new_dist, nil
+ }
+ switch n := new_dist.(type) {
+ case Lognormal:
+ return multiplyLogDists(Lognormal{low: float64(o), high: float64(o)}, n), nil
+ case Scalar:
+ return Scalar(float64(o) * float64(n)), nil
+ default:
+ return operateDistsAsSamples(old_dist, new_dist, "*")
+ }
+ }
+ case Beta:
+ switch n := new_dist.(type) {
+ case Beta:
+ return multiplyBetaDists(o, n), nil
+ default:
+ return operateDistsAsSamples(old_dist, new_dist, "*")
+ }
+ default:
+ return operateDistsAsSamples(old_dist, new_dist, "*")
+ }
+}
+
+func divideDists(old_dist Dist, new_dist Dist) (Dist, error) {
+
+ switch o := old_dist.(type) {
+ case Lognormal:
+ {
+ switch n := new_dist.(type) {
+ case Lognormal:
+ // to do: check division by zero
+ if n.high == 0 || n.low == 0 {
+ fmt.Println("Error: Can't divide by 0.0")
+ return nil, errors.New("Error: division by zero")
+ }
+ return multiplyLogDists(o, Lognormal{low: 1.0 / n.high, high: 1.0 / n.low}), nil
+ case Scalar:
+ // to do: check division by zero
+ if n == 0.0 {
+ fmt.Println("Error: Can't divide by 0.0")
+ return nil, errors.New("Error: division by zero scalar")
+ }
+ return multiplyLogDists(o, Lognormal{low: 1.0 / float64(n), high: 1.0 / float64(n)}), nil
+ default:
+ return operateDistsAsSamples(old_dist, new_dist, "/")
+ }
+ }
+ case Scalar:
+ {
+ switch n := new_dist.(type) {
+ case Lognormal:
+ return multiplyLogDists(Lognormal{low: float64(o), high: float64(o)}, Lognormal{low: 1.0 / n.high, high: 1.0 / n.low}), nil
+ case Scalar:
+ // to do: check division by zero
+ if n == 0.0 {
+ fmt.Println("Error: Can't divide by 0.0")
+ return nil, errors.New("Error: division by zero scalar")
+ }
+ return Scalar(float64(o) / float64(n)), nil
+ default:
+ return operateDistsAsSamples(old_dist, new_dist, "/")
+ }
+ }
+ default:
+ return operateDistsAsSamples(old_dist, new_dist, "/")
+ }
+}
+
+// Generic distribution operations
+func operateDists(old_dist Dist, new_dist Dist, op string) (Dist, error) {
+ switch op {
+ case "*":
+ return multiplyDists(old_dist, new_dist)
+ case "/":
+ return divideDists(old_dist, new_dist)
+ case "+":
+ return operateDistsAsSamples(old_dist, new_dist, "+")
+ case "-":
+ return operateDistsAsSamples(old_dist, new_dist, "-")
+ default:
+ return nil, printAndReturnErr("Can't combine distributions in this way")
+ }
+}
+
+/* Parser and repl */
+func parseLineIntoOpAndDist(line string) (string, Dist, error) {
+
+ words := strings.Split(strings.TrimSpace(line), " ")
+ op := ""
+ var dist Dist
+
+ switch words[0] {
+ case "*", "/", "+", "-":
+ op = words[0]
+ words = words[1:]
+ default:
+ op = "*" // later, change the below to
+ }
+
+ parseLineErr := func(err_msg string) (string, Dist, error) {
+ return "", nil, printAndReturnErr(err_msg)
+ }
+
+ switch len(words) {
+ case 0:
+ return parseLineErr("Operator must have operand; can't operate on nothing")
+ case 1:
+ single_float, err := strconv.ParseFloat(words[0], 64) // abstract this away to search for K/M/B/T/etc.
+ if err != nil {
+ return parseLineErr("Trying to operate on a scalar, but scalar is neither a float nor an assigned variable")
+ }
+ dist = Scalar(single_float)
+ case 2:
+ new_low, err1 := strconv.ParseFloat(words[0], 64)
+ new_high, err2 := strconv.ParseFloat(words[1], 64)
+ if err1 != nil || err2 != nil {
+ return parseLineErr("Trying to operate by a distribution, but distribution is not specified as two floats")
+ }
+ dist = Lognormal{low: new_low, high: new_high}
+ case 3:
+ if words[0] == "beta" || words[0] == "b" {
+ a, err1 := strconv.ParseFloat(words[1], 64)
+ b, err2 := strconv.ParseFloat(words[2], 64)
+ if err1 != nil || err2 != nil {
+ return parseLineErr("Trying to specify a beta distribution? Try beta 1 2")
+ }
+ dist = Beta{a: a, b: b}
+ } else {
+ return parseLineErr("Input not understood or not implemented yet")
+ }
+ default:
+ return parseLineErr("Input not understood or not implemented yet")
+ }
+ return op, dist, nil
+
+}
+
+func main() {
+ reader := bufio.NewReader(os.Stdin)
+ var old_dist Dist = INIT_DIST
+
+replForLoop:
+ for {
+
+ new_line, _ := reader.ReadString('\n')
+ words := strings.Split(strings.TrimSpace(new_line), " ")
+
+ switch {
+ case strings.TrimSpace(new_line) == "": /* Empty line case */
+ continue replForLoop
+ case words[0] == "exit" || words[0] == "e":
+ os.Exit(0)
+ case words[0] == "help" || words[0] == "h":
+ fmt.Println(HELP_MSG)
+ continue replForLoop
+ case words[0] == "debug" || words[0] == "d":
+ fmt.Printf("%v", old_dist)
+ continue replForLoop
+ case words[0] == "clear" || words[0] == "c" || words[0] == ".":
+ old_dist = INIT_DIST
+ fmt.Println()
+ continue replForLoop
+ }
+
+ op, new_dist, err := parseLineIntoOpAndDist(new_line)
+ if err != nil {
+ continue replForLoop
+ }
+ combined_dist, err := operateDists(old_dist, new_dist, op)
+ if err != nil {
+ continue replForLoop
+ }
+ old_dist = combined_dist
+ prettyPrintDist(old_dist)
+ }
+}
