cwhmisc (version 4.0)

convert: Test, convert numbers

Description

Functions for testing strings, for conversion of integers to bases other than decimal as string representations

Usage

allDigits( str )
isNumeric(str)
intToASCII(i)
intToBase( i, base=2 )
intToOct( i )
intToHex( i )
contfrac( x, depth = 13, f=floor ) 
evalcfr( cf )
toFrac( x, depth)
str2dig( str )
int( x )
xToBase( x, base=2 )
int( x )
Hd( h, m, s )
Hdms( hd )
Hmsd( hms )
Degree( radian )
Radian( degree )
ReduceArc( U, ref )
ReduceArc2(U, V, ref )
ToPolar( x, y )
ToRect( r, p )

Arguments

i,base,depth

Integer

x,y,r,p,h,m,s,hd,hms,U,V,ref,radian,degree

Real

f

function to use, normally 'floor', otherwise 'round' or 'trunc'

cf

Vector of integers representing the continued fraction of areal number

str

String

Details

alldigits Convert a string to a number literally. isNumeric Test whether the elements of a character vector represent legal numbers only. intToASCII Show character or octal representation at a place in the ASCII sequence. intToBase Convert an integer number to string representation in a base between 2 and 16 inclusive. intToOct Convert integer to octal representation. intToHex Convert integer to hex representation. contfrac Convert to continued fraction representation. evalcfr Evaluate continued fraction to corresponding real. toFrac Build rational approximation num/den to x using forward continued fraction recursion to a depth of depth. Stopping criterion: either depth is reached, or abs(x - num/den) is increasing again. str2dig Convert a string to a vector of integers. int truncate towards 0. xToBase return res$a, res$e so that x = a*base^e, abs( a ) in [1, base) sqr x^2. Hd Return hours from h, min, sec. Hms Return h, min, sec from hours, is inverse of Hd. Hdms Return hh.mmss from hours. Hmsd Decimal hours from hours.mmss, is inverse of Hdms. Degree Convert radians to degrees. Radian Convert degrees to radians. ReduceArc Add or subtract multiples of ref to make $abs(U) < ref/2$. ReduceArc2 Subtract from U and V the greatest multiple of ref, so that $0 <= min="" {u_new,="" v_new}="" <="" ref$.="" ToPolar,ToRect Convert rectangular into polar coordinates and vice versa. Further explanation in function code.

Examples

allDigits(c("1231","89a8742")) #  TRUE FALSE
isNumeric(c("1231","8.9e-2",".7d2")) # [1]  TRUE  TRUE FALSE
intToASCII(1:255)[121:129] # "x"   "y"   "z"   "{"   "|"   "}"   "~"   "\177" "\200"
sapply(1:50,intToBase,2)
sapply(1:50,intToBase,7)
sapply(1:50,intToOct)
sapply(1:50,intToHex)
(pcf <- contfrac(pi)) # 3, 7, 15, 1, 292, 1, 1, 1, 2, 1, 3, 1, 14, 2, (1)
## last integer incorrect due to rounding errors
evalcfr(pcf)-pi # 0
str2dig("10010") # [1] 1 0 0 1 0
int(10^(7:10)) # 10000000 100000000 1000000000 NA
gcd(35,133) # 7
x <- exp(2.1)
xToBase(x,2);xToBase(x,3);xToBase(x,4) # 8.16617 =  1.02077*2^3 = 2.72206*3^1 = 2.04154*4^1
Hd( 12,25,17) # 12.421389
Hms(1.421389) # $h  1, $m 25, $s 17.0004
Hmsd(1.421389) # 1h 42m 13.89 -> 1.703858
Hdms(1.703858) # 1.421389
Degree(pi/2)  # 90
Radian(180)  #  3.141593
ReduceArc(580,360) # -140
ReduceArc2(200,120,70) # 130, 50
ReduceArc2(100,-200,70) # 310, 10
ToPolar(1.0, 1.0) # $r 1.41421, $p 0.785398
ToRect(2.0,pi) # $x -2, $y 2.44921e-16