From 2b79f3f9cabc9d97f6385940072cc10f380ef626 Mon Sep 17 00:00:00 2001
From: Thomas von Dein <tom@vondein.org>
Date: Sun, 5 Nov 2023 17:39:15 +0100
Subject: [PATCH] updated docs

---
 calc.go | 30 +++++++++++++++++++-----------
 rpn.go  | 34 +++++++++++++++++++++++++---------
 rpn.pod | 34 +++++++++++++++++++++++++---------
 3 files changed, 69 insertions(+), 29 deletions(-)

diff --git a/calc.go b/calc.go
index 14d8e89..be15743 100644
--- a/calc.go
+++ b/calc.go
@@ -56,22 +56,26 @@ history              display calculation history
 help|?               show this message
 quit|exit|c-d|c-c    exit program
 
-Available operators:
-basic operators: + - x /
+Operators:
+basic operators: + - x * / ^  (* is an alias of x)
 
-Available math functions:
-sqrt                 square root
-mod                  remainder of division (alias: remainder)
-max                  batch mode only: max of all values
-min                  batch mode only: min of all values
-mean                 batch mode only: mean of all values (alias: avg)
-median               batch mode only: median of all values
+Percent functions:
 %                    percent
 %-                   substract percent
 %+                   add percent
 
-Math operators:
-^                    power`
+Math functions (see https://pkg.go.dev/math):
+mod sqrt abs acos acosh asin asinh atan atan2 atanh cbrt ceil cos cosh
+erf erfc  erfcinv erfinv exp  exp2 expm1 floor  gamma ilogb j0  j1 log
+log10 log1p log2 logb pow round roundtoeven sin sinh tan tanh trunc y0
+y1 copysign dim hypot
+
+Batch functions:
+sum                  sum of all values (alias: +)
+max                  max of all values
+min                  min of all values
+mean                 mean of all values (alias: avg)
+median               median of all values`
 
 // commands, constants and operators,  defined here to feed completion
 // and our mode switch in Eval() dynamically
@@ -295,6 +299,10 @@ func (c *Calc) DoFuncall(funcname string) error {
 		function = c.Funcalls[funcname]
 	}
 
+	if function == nil {
+		panic("function not defined but in completion list")
+	}
+
 	var args Numbers
 	batch := false
 
diff --git a/rpn.go b/rpn.go
index 648a79e..1441cdb 100644
--- a/rpn.go
+++ b/rpn.go
@@ -116,20 +116,36 @@ DESCRIPTION
     You can use the shift command to remove the last number from the stack.
 
   BUILTIN OPERATORS AND FUNCTIONS
-    Basic operators: + - x /
+    Basic operators:
 
-    Math functions:
+        +                    add
+        -                    substract
+        /                    divide
+        x                    multiply (alias: *)
+        ^                    power
+
+    Percent functions:
 
-        sqrt                 square root
-        mod                  remainder of division (alias: remainder)
-        max                  batch mode only: max of all values
-        min                  batch mode only: min of all values
-        mean                 batch mode only: mean of all values (alias: avg)
-        median               batch mode only: median of all values
         %                    percent
         %-                   substract percent
         %+                   add percent
-        ^                    power
+
+    Batch functions:
+
+        sum                  sum of all values (alias: +)
+        max                  max of all values
+        min                  min of all values
+        mean                 mean of all values (alias: avg)
+        median               median of all values
+
+    Math functions:
+
+        mod sqrt abs acos acosh asin asinh atan atan2 atanh cbrt ceil cos cosh
+        erf erfc  erfcinv erfinv exp  exp2 expm1 floor  gamma ilogb j0  j1 log
+        log10 log1p log2 logb pow round roundtoeven sin sinh tan tanh trunc y0
+        y1 copysign dim hypot
+
+    Refer to https://pkg.go.dev/math for details about those functions.
 
 EXTENDING RPN USING LUA
     You can use a lua script with lua functions to extend the calculator. By
diff --git a/rpn.pod b/rpn.pod
index 994695f..d37e285 100644
--- a/rpn.pod
+++ b/rpn.pod
@@ -123,20 +123,36 @@ stack.
 
 =head2 BUILTIN OPERATORS AND FUNCTIONS
 
-Basic operators: + - x /
+Basic operators:
 
-Math functions:
+    +                    add
+    -                    substract
+    /                    divide
+    x                    multiply (alias: *)
+    ^                    power
+
+Percent functions:
 
-    sqrt                 square root
-    mod                  remainder of division (alias: remainder)
-    max                  batch mode only: max of all values
-    min                  batch mode only: min of all values
-    mean                 batch mode only: mean of all values (alias: avg)
-    median               batch mode only: median of all values
     %                    percent
     %-                   substract percent
     %+                   add percent
-    ^                    power
+
+Batch functions:
+
+    sum                  sum of all values (alias: +)
+    max                  max of all values
+    min                  min of all values
+    mean                 mean of all values (alias: avg)
+    median               median of all values
+
+Math functions:
+
+    mod sqrt abs acos acosh asin asinh atan atan2 atanh cbrt ceil cos cosh
+    erf erfc  erfcinv erfinv exp  exp2 expm1 floor  gamma ilogb j0  j1 log
+    log10 log1p log2 logb pow round roundtoeven sin sinh tan tanh trunc y0
+    y1 copysign dim hypot
+
+Refer to https://pkg.go.dev/math for details about those functions.
 
 =head1 EXTENDING RPN USING LUA