diff --git a/README.md b/README.md
index 4bb06b4..5d66e12 100644
--- a/README.md
+++ b/README.md
@@ -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
-=> 5.0M 12.0M
-* beta 1 200  # fraction of people that have a piano
-1.9K 123.1K
-30 180        # minutes it takes to tune a piano, including travel time
-122.9K 11.7M
-/ 48 52       # weeks a year pianotuners work for
-2.5K 234.6K
-/ 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
+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
 ```
 
-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
-    * 1 10 (interpreted as lognormal)
+                    # this is a comment
+    / 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)
-      =: x
-    .
+    1 10            # multiplication taken as default operation)
+    =: x
+    .               # return the stack to 1.
     1 100
     + x
-    # this is a comment
-    * 1 12 # this is an operation followed by a comment
+    * 1 12 
+    * (
+    1 10
+    + beta 1 100
+    )
+    =. y            # save to variable and clear stack
     exit
 ```
 
@@ -160,11 +134,12 @@ 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
 
 To (possibly) do:
 
 - [ ] Specify number of samples as a command line option
-- [ ] Document parenthesis syntax
+- [ ] Figure out how to make models executable, by adding a #!/bin/bash-style command at the top?
 - [ ] 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
diff --git a/f.go b/f.go
index 67e7b65..34878cb 100644
--- a/f.go
+++ b/f.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 = 1_000_000
 
 /* Printers */
 func prettyPrintDist(dist Dist) {
@@ -408,6 +410,10 @@ replForLoop:
 }
 
 func main() {
+	num_samples_flag := flag.Int("n", N_SAMPLES, "Specifies the number of samples to draw when using samples")
+	flag.Parse()
+	N_SAMPLES = *num_samples_flag
+
 	reader := bufio.NewReader(os.Stdin)
 	stack := Stack{old_dist: INIT_DIST, vars: make(map[string]Dist)}
 	runRepl(stack, reader)
diff --git a/more/piano-tuners-commented.f b/more/piano-tuners-commented.f
deleted file mode 100644
index 9590255..0000000
--- a/more/piano-tuners-commented.f
+++ /dev/null
@@ -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
-
diff --git a/more/piano-tuners-commented.fermi b/more/piano-tuners-commented.fermi
new file mode 100644
index 0000000..190d47f
--- /dev/null
+++ b/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