User Manual

112 Alphabetical Listing
polyRoots()
Catalog >
polyRoots(Poly,Var) ⇒ list
polyRoots(ListOfCoeffs) ⇒ list
The first syntax, polyRoots(Poly,Var),
returns a list of real roots of polynomial
Poly with respect to variable Var. If no real
roots exist, returns an empty list: {}.
Poly must be a polynomial in expanded
form in one variable. Do not use
unexpanded forms such as y
2
•y+1 or
x•x+2•x+1
The second syntax, polyRoots
(ListOfCoeffs), returns a list of real roots
for the coefficients in ListOfCoeffs.
Note: See also cPolyRoots(), page 30.
PowerReg
Catalog >
PowerReg X,Y[, Freq][, Category, Include]]
Computes the power regressiony = (a•(x)
b
)
on lists X and Y with frequency Freq. A
summary of results is stored in the
stat.results variable. (See page 145.)
All the lists must have equal dimension
except for Include.
X and Y are lists of independent and
dependent variables.
Freq is an optional list of frequency values.
Each element in Freq specifies the
frequency of occurrence for each
corresponding X and Y data point. The
default value is 1. All elements must be
integers ≥ 0.
Category is a list of numeric or string
category codes for the corresponding X and
Y data.
Include is a list of one or more of the
category codes. Only those data items
whose category code is included in this list
are included in the calculation.