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min()

Usage:
min(x [,squeeze:T] [,silent:T,undefval:U]), x REAL or LOGICAL or a
  structure with REAL or LOGICAL components, U a REAL scalar
min(x, dimensions:J [,squeeze:T] [,silent:T,undefval:U]), vector of
  positive integers J
min(x, margins:K [,squeeze:F] [,silent:T,undefval:U]), vector of
  positive integers K
min(x1,x2,... [,silent:T,undefval:U]), x1, x2, ... REAL or LOGICAL
  vectors, all the same type.



Keywords: descriptive statistics
min(x) computes the minimum of the elements of a REAL or LOGICAL vector
x.

If x is LOGICAL, True is interpreted as 1.0 and False as 0.0 and hence
min(x) is 0.0 if any element of x is False, and 1.0 if all elements are
True.

If x is a m by n matrix, min(x) computes a row vector (1 by n matrix)
consisting of the minima of the elements in each column of x.

If x is an array with dimensions n1, n2, n3, ..., y <- min(x) computes
an array with dimensions 1, n2, n3, ... such that y[1,j,k,...] =
min(x[i,j,k,...], i=1,...,n1).  This is consistent with what happens
when x is a matrix.  Note: MacAnova3.35 and earlier produced a result
with dimensions n2, n3, ... .

min(x, squeeze:T) does the same, except the first dimension of the
result (of length 1) is squeezed out unless the result is a scalar.  In
particular, if x is a matrix, min(x,squeeze:T) will be identical to
vector(min(x)), and if x is an array, min(x,squeeze:T) will be identical
to array(min(x),dim(x)[-1]).

min(NULL) is NULL.

min(a,b,c,...) is equivalent to min(vector(a,b,c,...)) if a, b, c,
... are all vectors.  They must all have the same type, REAL or LOGICAL,
or be NULL.  min(NULL, NULL, ..., NULL) is NULL.

min(x, silent:T) or min(a,b,c,...,silent:T) does the same but suppresses
warning messages about MISSING values.

If all the elements of a vector x are MISSING, min(x) is MISSING.

min(x, undefval:U), where U is a REAL scalar does the same, except the
returned value is U when all the elements of x are MISSING.

min(x, dimensions:J [,squeeze:T] [,silent:T] [undefval:U]) finds the
minimum over the dimensions in J = vector(j1,j2,...,jn) where j1, ...,
jn are distinct positive integers <= ndims(x).  Without 'squeeze:T', the
result has the same number of dimensions as x, with dimensions j1, j2,
..., jn of length 1.  With 'squeeze:T', these dimensions are removed
from the result.  The order of j1, j2, ... is ignored.

It is an error if max(J) > ndims(x) or if there are duplicate elements
in J.

For example, if x is a matrix, min(x, dimensions:2) computes the row
minima as a nrows(x) by 1 matrix and min(x, dimensions:2,squeeze:T)
computes them as a one dimensional vector.

min(x, margins:K [,squeeze:F] [,silent:T] [undefval:U]) finds the minima
over the dimensions not in K = vector(k1, k2, ..., km), where k1, ...,
km are distinct positive integers <= ndims(x).  This computes minima for
the margins specified in K.

Without 'squeeze:F', only the dimensions in K are retained in the
result.  Otherwise the other dimensions are retained but have length 1.
This is opposite from the default with 'dimensions:J'.

It is an error if max(K) > ndims(x) or if there are duplicate elements
in K.

If x is a structure, min(x [dimensions:J or margins:K] [,squeeze:T or F]
[,silent:T] [undefval:U]) computes a structure, each of whose components
is min() applied to that component of x.

Examples:
  Cmd> x # matrix with labels
              B1          B2
  A1          18          15
  A2          17          26
  A3          18          19

  Cmd> min(x) # minima down columns
               B1          B2
  (1)          17          15

  Cmd> min(x,dimensions:2) # minima across rows; 3 by 1 matrix
             (1)
  A1          15
  A2          17
  A3          18

  Cmd> min(x,dimensions:2,squeeze:T) # same, length 3 vector
            A1          A2          A3
            15          17          18

  Cmd> min(x,margins:1) # same as preceding
            A1          A2          A3
            15          17          18

See also topics max(), 'NULL'.


Gary Oehlert 2003-01-15