RandomFields (version 3.1.16)

Mathematial C functions: Transformation of coordinate systems

Description

The functions provide mathematical c functions as RMmodels

Usage

RFcalc(model)
R.minus(a, b, factor)
R.plus(a, b, factor)
R.div(a, b, factor)
R.mult(a, b, factor)
R.const(a)
R.c(a, b, c, d, e, f, g, h, i, j, factor)
R.p(proj, new, factor)
R.is(a, is, b)
R.lon()
R.lat()
R.acos(a)
asin(x)
R.asin(a)
atan(x)
R.atan(a)
atan2(y, x)
R.atan2(a, b)
cos(x)
R.cos(a)
sin(x)
R.sin(a)
tan(x)
R.tan(a)
acosh(x)
R.acosh(a)
asinh(x)
R.asinh(a)
atanh(x)
R.atanh(a)
cosh(x)
R.cosh(a)
sinh(x)
R.sinh(a)
tanh(x)
R.tanh(a)
exp(x)
R.exp(a)
log(x)
R.log(a)
expm1(x)
R.expm1(a)
log1p(x)
R.log1p(a)
logb(x)
R.logb(a)
R.exp2(a)
log2(x)
R.log2(a)
R.pow(a, b)
sqrt(x)
R.sqrt(a)
R.hypot(a, b)
R.cbrt(a)
R.ceil(a)
abs(x)
R.fabs(a)
floor(x)
R.floor(a)
R.fmod(a, b)
R.nearbyint(a)
round(x, ...)
R.round(a)
trunc(x)
R.trunc(a)
R.lrint(a)
R.llrint(a)
R.lround(a)
R.llround(a)
R.copysign(a, b)
R.erf(a)
R.erfc(a)
gamma(x)
R.tgamma(a)
lgamma(x)
R.lgamma(a)
R.rint(a)
R.nextafter(a, b)
R.nexttoward(a, b)
R.remainder(a, b)
R.fdim(a, b)
max(...)
R.fmax(a, b)
min(...)
R.fmin(a, b)

Arguments

model

object of class RMmodel, in particular R.model

x,y,a, b, c, d, e, f, g, h, i, j, ...

constant or object of class RMmodel, in particular R.model

is

one of "==", "!=", "<="< code="">, "<"< code="">, ">=", ">"

factor

constant factor multiplied with the function. This is useful when linear models are built

proj

selection of a component of the vector giving the location. Default value is 1.

new

coordinate system or other kind of isotropy which is supposed to be present at this model. It shold always be given if the coordinates are not cartesian.

Value

Formally, the functions returns an object of class RMmodel, except for RFcalc that returns a scalar. Neither vectors nor parentheses are allowed.

Details

R.plus

adds two values

R.minus

substracts two values

R.mult

multiplies two values

R.div

devides two values

R.const

defines a constant

R.c

builds a vector

R.is

evaluates equalities and inequalities; note that TRUE is returned if the equality or inequality holds up to a tolerance given by RFoptions()$nugget$tol

R.p

takes a component out of the vector giving the location

R.lon, R.lat

longitudinal and latitudinal coordinate, given in the spherical system, i.e. in radians. (earth system is in degrees).

Sor the remaining models see the corresponding C functions for their return value. (For any ‘R.model’ type ‘man model’ under Linux.)

See Also

RMmodel, RFfctn, RMtrend

Examples

RFoptions(seed=0) ## *ANY* simulation will have the random seed 0; set
##                   RFoptions(seed=NA) to make them all random again

## simple calculation
RFcalc(3 + R.sin(pi/4))

## calculation performed on a field
RFfctn(R.p(1) + R.p(2), 1:3, 1:3) 
RFfctn(10 + R.p(2), 1:3, 1:3) 

## calculate the distances between two vectors
print(RFfctn(R.p(new="iso"), 1:10, 1:10))

## simulation of a non-stationary field where
## anisotropy by a transform the coordinates (x_1^2, x_2^1.5)
x <- seq(0.1, 6, 0.12)
Aniso <- R.c(R.p(1)^2, R.p(2)^1.5)
z <- RFsimulate(RMexp(Aniso=Aniso), x, x)


## calculating norms can be abbreviated:
x <- seq(-5, 5, 5) #0.1)
z2 <- RFsimulate(RMexp() + -40 + exp(0.5 * R.p(new="isotropic")), x, x)
z1 <- RFsimulate(RMexp() + -40 + exp(0.5 * sqrt(R.p(1)^2 + R.p(2)^2)), x, x)
stopifnot(all.equal(z1, z2))
plot(z1)