Manual

Functions and commands 409
propfrac Returns a fraction or rational fraction A/B simplified to Q+r/
B, where R<B or the degree of R is less than the degree of B.
propfrac(Fraction) or propfrac(RatFrac)
Example:
propfrac(28/12) gives 2+1/3
ptayl Given a polynomial P and a value a, returns the Taylor
polynomial Q such that P(x)=Q(x – a).
ptayl(Poly, Value, [Var])
Example:
ptayl(x^2+2*x+1,1) gives x^2+4*x+4
purge Unassigns a variable name.
purge(Var)
q2a Given a quadratic form and a vector of variables, returns the
matrix of the quadratic form with respect to the given
variables.
q2a(Expr, Vector)
Example:
q2a(x^2+2*x*y+2*y^2,[x,y]) returns
quantile Given a list or vector, and a quantile value between 0 and 1,
returns the corresponding quantile of the elements of the list
or vector.
quantile(List, Value) or
quantile(Vector, Value)
Example:
quantile([0,1,3,4,2,5,6],0.25) returns 1
quartile1 Given a list or vector, returns the first quartile of the elements
of the list or vector. Given a matrix, returns the first quartile of
the columns of the matrix.
quartile1(List) or quartile1(Vector) or
quartile1(Matrix)
Example:
quartile1([1,2,3,5,10,4]) gives 2
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