tweak: pretty print with more precision

README.md

@@ -1,6 +1,6 @@
-# A minimalist calculator for fermi estimation
+# A calculator for distributions, for Fermi estimation
 
-This project is a minimalist, calculator-style DSL for fermi estimation. It can multiply, divide, add and substract scalars, lognormals and beta distributions.
+This project is a minimalist, calculator-style DSL for fermi estimation. It can multiply, divide, add and substract scalars, lognormals and beta distributions, and supports variables.
 
 ## Motivation
 
@@ -21,66 +21,33 @@ $ fermi
 5000000 12000000
 => 5.0M 12.0M
 * beta 1 200
-1.9K 123.1K
+=> 1.9K 123.1K
 * 30 180
-122.9K 11.7M
+=> 122.9K 11.7M
 / 48 52
-2.5K 234.6K
+=> 2.5K 234.6K
 / 5 6
-448.8 43.0K
+=> 448.8 43.0K
 / 6 8
-64.5 6.2K
+=> 64.5 6.2K
 / 60
-1.1 103.7
+=> 1.1 103.7
 ```
 
 Perhaps this example is more understandable with comments and better units:
 
 ```
 $ fermi
-5M 12M        # number of people living in Chicago
+5M 12M           # number of people living in Chicago
-=> 5.0M 12.0M
+beta 1 200       # fraction of people that have a piano
-* beta 1 200  # fraction of people that have a piano
+30 180           # minutes it takes to tune a piano, including travel time
-1.9K 123.1K
+/ 48 52          # weeks a year that piano tuners work for
-30 180        # minutes it takes to tune a piano, including travel time
+/ 5 6            # days a week in which piano tuners work
-122.9K 11.7M
+/ 6 8            # hours a day in which piano tuners work
-/ 48 52       # weeks a year pianotuners work for
+/ 60             # minutes to an hour
-2.5K 234.6K
+=: piano_tuners
-/ 6 8         # hours a day
-353.9 34.1K
-/ 60          # minutes to an hour
-5.9 568.3
-=: piano_tuners_in_Chicago
-piano_tuners_in_Chicago => 5.9 568.3
 ```
 
-Here is instead an example using beta distributions and variables:
-
-```
-$ fermi
-1 2
-=> 1.0 2.0
-* 1_000_000_000
-=> 1000.0M 2.0B
-=: x # assign to variable
-x => 1000.0M 2.0B
-. # clear the stack, i.e., make it be 1
-
-beta 1 2
-=> beta 1.0 2.0
-beta 12 300
-=> beta 13.0 302.0
-=. y # assign to variable and clear the stack (return it to 1)
-y => beta 13.0 302.0
-
-x
-=> 1000.0M 2.0B
-* y
-=> samples 31.3M 98.2M
-```
-
-The difference between `=: x` and `=. y` is that `=.` clears the stack after the assignment.
-
 If you type "help", you can see a small grammar:
 
 ```
@@ -95,24 +62,31 @@ help
     Variable assignment:                   =: variable_name
     Variable assignment and clear stack:   =. variable_name
     Special:
-         Clear stack:                      clear | c | .
-         Print this help message:          help  | h
-         Print debug info:                 debug | d
-         Exit:                             exit  | e
          Comment:                          # this is a comment
+         Clear stack:                      clear | c | .
+         Print debug info:                 debug | d
+         Print help message:               help  | h
+         Start additional stack:           operator (
+         Return from additional stack      )
+         Exit:                             exit  | e
   Examples:
     + 2
-    / 2.5
+                    # this is a comment
-    * 1 10 (interpreted as lognormal)
+    / 2.5           # this is an operation followed by a comment
+    * 1 10          # "low high" is interpreted as lognormal
     + 1 10
     * beta 1 10
-    1 10 (multiplication taken as default operation)
+    1 10            # multiplication taken as default operation)
-      =: x
+    =: x
-    .
+    .               # return the stack to 1.
     1 100
     + x
-    # this is a comment
+    * 1 12 
-    * 1 12 # this is an operation followed by a comment
+    * (
+    1 10
+    + beta 1 100
+    )
+    =. y            # save to variable and clear stack
     exit
 ```
 
@@ -120,11 +94,45 @@ help
 
 - It's conceptually clearer to have all the multiplications first and then all the divisions
 - For things between 0 and 1, consider using a beta distribution
-- Because the model reads from standard input, you can pipe a model to it. For instance, try cat more/piano-tuners.f | fermi
+
+### Command line options
+
+You can specify the number of samples to draw when algebraic manipulations are not sufficient: 
+
+```
+$ fermi -n 1000000
+$ fermi -n 1_000_000
+```
+
+You also run a file with the -f option
+
+```
+$ fermi -f more/piano-tuners.fermi 
+```
+
+### Integrations with linux utilities
+
+Because the model reads from standard input, you can a model to it:
+
+```
+$ cat more/piano-tuners.fermi | fermi
+```
+
+You can make a model an executable file by running `$ chmod -x model.fermi` and then adding the following at the top!
+
+```
+#!/bin/usr/fermi -f
+```
+
+You can save a session to a logfile with tee:
+
+```
+fermi | tee -a fermi.log
+```
 
 ## Different levels of complexity
 
-The top level f.go file (400 lines) has a bunch of complexity: variables, parenthesis, samples, beta distributions. In the simple/ folder:
+The top level f.go file (420 lines) has a bunch of complexity: variables, parenthesis, samples, beta distributions, number of samples, etc. In the simple/ folder:
 
 - f_simple.go (370 lines) strips variables and parenthesis, but keeps beta distributions, samples, and addition and substraction
 - f_minimal.go (140 lines) strips everything that isn't lognormal and scalar multiplication and addition, plus a few debug options.
@@ -159,11 +167,14 @@ Done:
 - [x] Clean up error code. Right now only needed for division
 - [x] Maintain *both* a more complex thing that's more featureful *and* the more simple multiplication of lognormals thing.
 - [x] Allow input with K/M/T
+- [x] Document parenthesis syntax
+- [x] Specify number of samples as a command line option
+- [x] Figure out how to make models executable, by adding a #!/bin/bash-style command at the top?
+- [x] Make -n flag work
+- [x] Add flag to repeat input lines (useful when reading from files)
 
 To (possibly) do:
 
-- [ ] Specify number of samples as a command line option
-- [ ] Document parenthesis syntax
 - [ ] Add functions. Now easier to do with an explicit representation of the stakc
 - [ ] Think about how to draw a histogram from samples
 - [ ] Dump samples to file

fermi.go

@@ -3,6 +3,7 @@ package main
 import (
 	"bufio"
 	"errors"
+	"flag"
 	"fmt"
 	"git.nunosempere.com/NunoSempere/fermi/pretty"
 	"git.nunosempere.com/NunoSempere/fermi/sample"
@@ -101,7 +102,8 @@ const HELP_MSG = "  Operation | Variable assignment | Special\n" +
 
 const NORMAL90CONFIDENCE = 1.6448536269514727
 const INIT_DIST Scalar = Scalar(1)
-const N_SAMPLES = 1_000_000
+
+var N_SAMPLES = 100_000
 
 /* Printers */
 func prettyPrintDist(dist Dist) {
@@ -354,10 +356,13 @@ func parseWordsIntoOpAndDist(words []string, vars map[string]Dist) (string, Dist
 // We want this as a function (rather than just be in main)
 // to be able to have parenthesis/recusion, possibly functions
 
-func runRepl(stack Stack, reader *bufio.Reader) Stack {
+func runRepl(stack Stack, reader *bufio.Reader, echo_flag *bool) Stack {
 replForLoop:
 	for {
 		new_line, _ := reader.ReadString('\n')
+		if *echo_flag {
+			fmt.Printf(new_line)
+		}
 		new_line_before_comments, _, _ := strings.Cut(new_line, "#")
 		new_line_trimmed := strings.TrimSpace(new_line_before_comments)
 		words := strings.Split(new_line_trimmed, " ")
@@ -367,7 +372,7 @@ replForLoop:
 			continue replForLoop
 		/* Parenthesis */
 		case len(words) == 2 && (words[0] == "*" || words[0] == "+" || words[0] == "-" || words[0] == "/") && words[1] == "(":
-			new_stack := runRepl(Stack{old_dist: INIT_DIST, vars: stack.vars}, reader)
+			new_stack := runRepl(Stack{old_dist: INIT_DIST, vars: stack.vars}, reader, echo_flag)
 			combined_dist, err := operateDists(stack.old_dist, new_stack.old_dist, words[0])
 			if err == nil {
 				stack.old_dist = combined_dist
@@ -408,7 +413,25 @@ replForLoop:
 }
 
 func main() {
-	reader := bufio.NewReader(os.Stdin)
+	num_samples_flag := flag.Int("n", N_SAMPLES, "Specifies the number of samples to draw when using samples")
+	filename := flag.String("f", "", "Specifies a file with a model to run")
+	echo_flag := flag.Bool("echo", false, "Specifies whether inputs should be echoed back. Useful if reading from a file.")
+	flag.Parse()
+	N_SAMPLES = *num_samples_flag
+
+	var reader *bufio.Reader = nil
+	if *filename != "" {
+		file, err := os.Open(*filename)
+		if err == nil {
+			reader = bufio.NewReader(file)
+		} else {
+			fmt.Printf("Error opening filename; reading from stdin instead\n")
+		}
+	}
+	if reader == nil {
+		reader = bufio.NewReader(os.Stdin)
+	}
 	stack := Stack{old_dist: INIT_DIST, vars: make(map[string]Dist)}
-	runRepl(stack, reader)
+	runRepl(stack, reader, echo_flag)
+
 }

makefile

@@ -1,17 +1,11 @@
-run:
-	go run f.go
-
 build:
-	go build f.go
+	go build fermi.go
 
-install: f 
+run:
+	go run fermi.go
+
+install: fermi 
 	rm /usr/bin/fermi
 	rm /usr/bin/f
-	sudo mv f /usr/bin/f
+	sudo mv fermi /usr/bin/fermi
-	sudo ln -s /usr/bin/f /usr/bin/fermi
+	sudo ln -s /usr/bin/fermi /usr/bin/f
-
-install_xl: f 
-	rm /usr/bin/fermixl
-	rm /usr/bin/fxl
-	sudo mv f /usr/bin/fxl
-	sudo ln -s /usr/bin/fxl /usr/bin/fermixl

more/executable-model.fermi

@@ -0,0 +1,10 @@
+#!/bin/fermi -f
+5M 12M     # number of people living in Chicago
+beta 1 200 # fraction of people that have a piano
+30 180     # minutes it takes to tune a piano, including travel time
+/ 48 52    # weeks a year that piano tuners work for
+/ 5 6      # days a week in which piano tuners work
+/ 6 8      # hours a day in which piano tuners work
+/ 60       # minutes to an hour
+=: piano_tuners
+exit

more/piano-tuners-commented.f

@@ -1,9 +0,0 @@
-5M 12M # number of people living in Chicago
-0.002 0.01 # fraction of people that have a piano
-30 180 # minutes it takes to tune a piano, including travel time
-/ 48 52 # weeks a year that piano tuners work for
-/ 5 6 # days a week in which piano tuners work
-/ 6 8 # hours a day in which piano tuners work
-/ 60 # minutes to an hour
-# ^ piano tuners in Chicago
-

more/piano-tuners-commented.fermi

@@ -0,0 +1,9 @@
+5M 12M     # number of people living in Chicago
+beta 1 200 # fraction of people that have a piano
+30 180     # minutes it takes to tune a piano, including travel time
+/ 48 52    # weeks a year that piano tuners work for
+/ 5 6      # days a week in which piano tuners work
+/ 6 8      # hours a day in which piano tuners work
+/ 60       # minutes to an hour
+=: piano_tuners
+exit

pretty/pretty.go

@@ -10,13 +10,13 @@ import (
 func PrettyPrintInt(n int) {
 	switch {
 	case math.Abs(float64(n)) >= 1_000_000_000_000:
-		fmt.Printf("%dT", n/1_000_000_000_000)
+		fmt.Printf("%.2fT", float64(n)/1_000_000_000_000.0)
 	case math.Abs(float64(n)) >= 1_000_000_000:
-		fmt.Printf("%dB", n/1_000_000_000)
+		fmt.Printf("%.2fB", float64(n)/1_000_000_000.0)
 	case math.Abs(float64(n)) >= 1_000_000:
-		fmt.Printf("%dM", n/1_000_000)
+		fmt.Printf("%.2fM", float64(n)/1_000_000.0)
 	case math.Abs(float64(n)) >= 1_000:
-		fmt.Printf("%dK", n/1_000)
+		fmt.Printf("%.2fK", float64(n)/1_000.0)
 	default:
 		fmt.Printf("%df", n)
 	}
@@ -25,24 +25,24 @@ func PrettyPrintInt(n int) {
 func PrettyPrintFloat(f float64) {
 	switch {
 	case math.Abs(f) >= 1_000_000_000_000:
-		fmt.Printf("%.1fT", f/1_000_000_000_000)
+		fmt.Printf("%.2fT", f/1_000_000_000_000)
 	case math.Abs(f) >= 1_000_000_000:
-		fmt.Printf("%.1fB", f/1_000_000_000)
+		fmt.Printf("%.2fB", f/1_000_000_000)
 	case math.Abs(f) >= 1_000_000:
-		fmt.Printf("%.1fM", f/1_000_000)
+		fmt.Printf("%.2fM", f/1_000_000)
 	case math.Abs(f) >= 1_000:
-		fmt.Printf("%.1fK", f/1_000)
+		fmt.Printf("%.2fK", f/1_000)
 
 	case math.Abs(f) <= 0.0001:
-		fmt.Printf("%.5f", f)
+		fmt.Printf("%.6f", f)
 	case math.Abs(f) <= 0.001:
-		fmt.Printf("%.4f", f)
+		fmt.Printf("%.5f", f)
 	case math.Abs(f) <= 0.01:
-		fmt.Printf("%.3f", f)
+		fmt.Printf("%.4f", f)
 	case math.Abs(f) <= 0.1:
-		fmt.Printf("%.2f", f)
+		fmt.Printf("%.3f", f)
 	default:
-		fmt.Printf("%.1f", f)
+		fmt.Printf("%.2f", f)
 	}
 
 }