Last modified :
September 9 2006

# Functions

HELP-button
  A whole list with all the functions suported by Eureka.

ln = natural logarithm
  x = ln(ex)

log = base 10 logarithm
  x = log(10x)

imaginary unit : i
  The imaginary unit is also often written as j (see curves of Bode), especially there were electrical currents are involved in the calculations and parameters. Current has also as symbol i.
The definition of i can be written as follows : i*i = -1.
Another way to see this is like this : sqrt(-1) = i (don't forget this is a faultly defenition because you can't take a sqrt from a negative number.)

Logic Operators :

& = logic AND
  This operator can be defined by next table :

X | Y | X&Y
--- | --- | ---
0 | 0 | 0
0 | 1 | 0
1 | 0 | 0
1 | 1 | 1

| = logic OR
  This operator can be defined by next table :

X | Y | X|Y
--- | --- | ---
0 | 0 | 0
0 | 1 | 1
1 | 0 | 1
1 | 1 | 1

! = logic NOT
  This operator can be defined by next table :

X | !X
--- | ---
0 | 1
1 | 0

Special symbols :

- !> = not superior to
- !< = not inferior to
- // = parallel e.g. R1//R2=R1*R2/(R1+R2)

The constant values :

- pi = PI = 3.141592654
- eu = e = 2.718281828
- i = imaginary unit

Set of available functions :

    "asinh"		ex : asinh(x)
    "acosh"		ex : acosh(x)
    "atgh"		ex : atgh(x)
    "abs"		ex : abs(x)
    "ash"		ex : ash(x)
    "ach"		ex : ach(x)
    "ath"		ex : ath(x)
    "atanh"		ex : atanh(x)
    "acos"		ex : acos(x)
    "asin"		ex : asin(x)
    "atg"		ex : atg(x)
    "atan"		ex : atan(x)
    "arg"		ex : arg(x+i*y)
    "cos"		ex : cos(x)
    "ch"		ex : ch(x)
    "coth"		ex : coth(x)
    "cotanh"	ex : cotanh(x)
    "cotg"		ex : cotg(x)
    "cotan"		ex : cotan(x)
    "conj"		ex : conj(x+i*y)
    "ceil"		ex : ceil(x)
    "data"		ex : dataa(x)
    "dftd"		ex : dftda(x)
    "dfti"		ex : dftia(x)
    "degrees"	ex : degrees(Pi/2.0)
    "exp"		ex : exp(x)
    "ent"		ex : ent(x)
    "err"		ex : err(x)
    "fac"		ex : fac(x)
    "floor"		ex : floor(x)
    "fit"		ex : fita(x)
    "fftd"		ex : fftda(x)
    "ffti"		ex : fftia(x)
    "gamma"		ex : gamma(x)
    "hside"		ex : hside(x)
    "int"		ex : int(x)
    "im"		ex : im(x+i*y)
    "inf"		ex : inf(x,y)
    "julia"		ex : julia(x+i*y,x+i*y)
    "j'"		ex : j'(x,y)
    "j"		ex : j(x,y)
    "ln"		ex : ln(x)
    "log"		ex : log(x)
    "line"		ex : linea(x)
    "max"		ex : max(x,y)
    "min"		ex : min(x,y)
    "mod"		ex : mod(x,y)
    "p10"		ex : p10(x)
    "pow"		ex : pow(x,y)
    "poly"		ex : polya(x)
    "psd"		ex : psda(x)
    "peak"		ex : peaka(10,x)
    "rand"		ex : rand(1000.0)
    "radians"	ex : radians(10.0)
    "rect"		ex : rect(x)
    "re"		ex : re(x+i*y)
    "sin"		ex : sin(x)
    "sqrt"		ex : sqrt(x)
    "sh"		ex : sh(x)
    "sgn"		ex : sgn(x)
    "sup"		ex : sup(x,y)
    "samp"		ex : sampa(x)
    "smooth"	ex : smootha(x)
    "spline"	ex : splinea(x)
    "surf"		ex : surfax(x,y)
    "th"		ex : th(x)
    "tanh"		ex : tanh(x)
    "tg"		ex : tg(x)
    "tan"		ex : tan(x)
    "wville"	ex : wvillea(x,y)

Set of available options (after a ";") :

    "iter="		ex : ;iter=256
    "angle="	ex : ;angle=180
    "!rotate"
    "!flip"
    "!logx"
    "!logy"
    "!norm"
    "!gridmax"
    "!gridmay"
    "!gridmix"
    "!gridmiy"
    "!gradmax"
    "!gradmay"
    "!gradmix"
    "!gradmiy"
    "rotate"
    "flip"
    "color="	ex : ;color=image
    "sub="		ex : ;sub=5
    "majgx="	ex : ;majgx=8
    "mingx="	ex : ;mingx=10
    "majgy="	ex : ;majgy=6
    "mingy="	ex : ;mingy=10
    "mesh="		ex : ;mesh=101*51
    "cmap="		ex : ;cmap=hot.map
    "ccmap="	ex : ;ccmap=jet.map
    "solid"
    "logx"
    "logy"
    "norm"
    "black"
    "noir"
    "white"
    "blanc"
    "gridmax"
    "gridmay"
    "gridmix"
    "gridmiy"
    "gradmax"
    "gradmay"
    "gradmix"
    "gradmiy"
    "mem"		ex : ;mem12=10.0

Set of available constants :

    "mem"			ex : mem12
    "i","I"			ex : cos(x)+i*sin(y)
    "pi","PI","Pi"		ex : Pi/2.0
    "eu","EU","Eu"		ex : pow(Eu,x)
    "m"			ex : m0
    "du"			ex : dua
    "fr"			ex : fra
    "xmin"			ex : xmina
    "xmax"			ex : xmaxa
    "ymin"			ex : ymina
    "ymax"			ex : ymaxa
    "time","clock"

More info will follow in the next version.