2014-01-03 00:42:00

1 files changed, 13 insertions, 10 deletions

diff --git a/metapost/context/base/mp-tool.mpiv b/metapost/context/base/mp-tool.mpiv
index 4ca2ea0f9..672a051c2 100644
--- a/metapost/context/base/mp-tool.mpiv
+++ b/metapost/context/base/mp-tool.mpiv
@@ -289,14 +289,10 @@ vardef set_outer_boundingbox text q = % obsolete
     setbounds q to outerboundingbox q;
 enddef;
 
-%D Some missing functions can be implemented rather straightforward (thanks to
-%D Taco and others):
+%D Some missing functions can be implemented rather
+%D straightforward:
 
-pi := 3.14159265358979323846 ; radian := 180/pi ; % 2pi*radian = 360 ;
-
-% let +++ = ++ ;
-
-numeric Pi ; Pi := pi ; % for some old compatibility reasons i guess
+numeric Pi ; Pi := 3.1415926 ;
 
 vardef sqr  primary x = x*x                                 enddef ;
 vardef log  primary x = if x=0: 0 else: mlog(x)/mlog(10) fi enddef ;
@@ -306,6 +302,15 @@ vardef inv  primary x = if x=0: 0 else: x**-1 fi            enddef ;
 
 vardef pow (expr x,p) = x**p                                enddef ;
 
+vardef asin primary x = x+(x**3)/6+3(x**5)/40               enddef ;
+vardef acos primary x = asin(-x)                            enddef ;
+vardef atan primary x = x-(x**3)/3+(x**5)/5-(x**7)/7        enddef ;
+vardef tand primary x = sind(x)/cosd(x)                     enddef ;
+
+%D Here are Taco Hoekwater's alternatives (but vardef'd and primaried).
+
+pi := 3.1415926 ; radian := 180/pi ; % 2pi*radian = 360 ;
+
 vardef tand   primary x = sind(x)/cosd(x)  enddef ;
 vardef cotd   primary x = cosd(x)/sind(x)  enddef ;
 
@@ -316,11 +321,9 @@ vardef cot    primary x = cos(x)/sin(x)    enddef ;
 
 vardef asin   primary x = angle((1+-+x,x)) enddef ;
 vardef acos   primary x = angle((x,1+-+x)) enddef ;
-vardef atan   primary x = angle(1,x)       enddef ;
 
 vardef invsin primary x = (asin(x))/radian enddef ;
 vardef invcos primary x = (acos(x))/radian enddef ;
-vardef invtan primary x = (atan(x))/radian enddef ;
 
 vardef acosh  primary x = ln(x+(x+-+1))    enddef ;
 vardef asinh  primary x = ln(x+(x++1))     enddef ;
@@ -1220,7 +1223,7 @@ enddef ;
 
 extra_endfig := extra_endfig & " naturalizepaths ; " ;
 
-%D Nice tracer:
+%D Noce tracer:
 
 def drawboundary primary p =
     draw p dashed evenly withcolor white ;