function sin(){ echo "scale=10; s($1*a(1)/90);" | bc -l; }

sin 30
.2588190450

sin 60
.4999999999

23:37 /Data
function sin(){ echo "scale=10; s($1*a(1)/45);" | bc -l; }
23:37 /Data
sin 45
.7071067811
23:37 /Data
sin 90
1.0000000000
23:37 /Data
sin 30
.4999999999

function cos(){ echo "scale=10; c($1*a(1)/45);" | bc -l; }
function tan(){ echo "scale=10; arg=$1*a(1)/45; s(arg)/c(arg);" | bc -l; }
function ln(){ echo "scale=10; l($1);" | bc -l; }
function log(){ echo "scale=10; l($1)/l(10);" | bc -l; }

$ python <<< `printf "import math\n\rprint math.sin(2)"`
0.909297426826

function fact()                                                                                                                                                                        
{                                                                                                                                                                                         
  if [ $# != 1 ]                                                                                                                                                                            
  then                                                                                                                                                                                      
    echo "FAIL" >&2                                                                                                                                                                           
    return 0                                                                                                                                                                                    
  fi                                                                                                                                                                                        
                                                                                                                                                                                          
  case $1 in                                                                                                                                                                                
    [01]) echo 1 ;;                                                                                                                                                                           
    *) n=`expr $1 - 1`                                                                                                                                                                        
      m=`fact $n`                                                                                                                                                                               
      echo `expr $1 \* $m`                                                                                                                                                                      
      ;;                                                                                                                                                                                        
  esac                                                                                                                                                                                      
} 

function power()
{
  if [ $# != 2 ]
  then
    echo "FAIL" >&2
    return 0
  fi

  result=1
  for f in `seq 1 $2`
  do
    result=$(( $result * $1 ))
  done
  echo $result
}

function sin()                                                                                                                                                                        
{                                                                                                                                                                                         
if [ $# != 2 ]                                                                                                                                                                            
then                                                                                                                                                                                      
  echo "FAIL" >&2                                                                                                                                                                         
  return 2                                                                                                                                                                                
fi                                                                                                                                                                                        
                                                                                                                                                                                          
result=$1                                                                                                                                                                                 
n=1                                                                                                                                                                                       
for k in `seq 2 $2`                                                                                                                                                                       
do                                                                                                                                                                                        
n=$((n + 2))                                                                                                                                                                              
result=$(( $result - 1.0 * `pow $1 $n` * `pow -1 $k` / `fact $n` ))                                                                                                                       
done                                                                                                                                                                                      
echo $result                                                                                                                                                                              
} 

function sin()
{
  if [ $# != 2 ]
  then
    echo "FAIL" >&2
    return 2
  fi

  result=$1
  x=$1
  n=1
  fact=1
  for k in `seq 2 $2`
  do
    x=$(( $x * $1 * $1 ))
    n=$(( $n + 2 ))
    fact=$(( (-1.0) * $fact * ($n - 1) * $n ))
    result=$(( $result + $x / $fact ))
  done
  echo $result
}

time ruby helloworld.rb

THE ZSH/MATHFUNC MODULE
       The zsh/mathfunc module provides standard mathematical functions for use when evaluating mathematical formulae.  The syntax agrees with
       normal C and FORTRAN conventions, for example,

              (( f = sin(0.3) ))

       assigns the sine of 0.3 to the parameter f.