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all

SYNOPSIS
  Tests if all elements of an array are non-zero

USAGE
  Char_Type all (Array_Type a [,Int_Type dim])

DESCRIPTION
  The `all' function examines the elements of a numeric array and
  returns 1 if all elements are non-zero, otherwise it returns 0. If a
  second argument is given, then it specifies the dimension of the
  array over which the function is to be applied.  In this case, the
  result will be an array with the same shape as the input array minus
  the specified dimension.

EXAMPLE
  Consider the 2-d array

1       2       3       4        5
      6       7       8       9       10

generated by

a = _reshape ([1:10], [2, 5]);

Then `all(a)' will return 1, and `all(a>3, 0)' will return
  a 1-d array

[0, 0, 0, 1, 1]

Similarly, `all(a>3, 1)' will return the 1-d array

[0,1]

SEE ALSO
  stat_file

--------------------------------------------------------------

chdir

SYNOPSIS
  Change the current working directory

USAGE
  Int_Type chdir (String_Type dir)

DESCRIPTION
  The `chdir' function may be used to change the current working
  directory to the directory specified by `dir'.  Upon success it
  returns zero.  Upon failure it returns `-1' and sets
  `errno' accordingly.

SEE ALSO
  stat_file

--------------------------------------------------------------

SYNOPSIS
  Expand the dollar-escaped variables in a string

USAGE
  String_Type _$(String_Type s)

DESCRIPTION
 This function expands the dollar-escaped variables in a string and
 returns the resulting string.

EXAMPLE
 Consider the following code fragment:

private variable Format = "/tmp/foo-$time.$pid";
     define make_filename ()
     {
        variable pid = getpid ();
        variable time = _time ();
        return _$(Format);
     }

Note that the variable `Format' contains dollar-escaped
 variables, but because the `$' suffix was omitted from the
 string literal, the variables are not expanded.  Instead expansion is
 deferred until execution of the `make_filename' function through
 the use of the `_$' function.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

acosh

SYNOPSIS
  Compute the inverse cosh of a number

USAGE
  y = acosh (x)

DESCRIPTION
  The `acosh' function computes the inverse hyperbolic cosine of a number and
  returns the result.  If its argument is an array, the
  `acosh' function will be applied to each element and the result returned
  as an array.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

asin

SYNOPSIS
  Compute the arc-sine of a number

USAGE
  y = asin (x)

DESCRIPTION
  The `asin' function computes the arc-sine of a number and
  returns the result.  If its argument is an array, the
  `asin' function will be applied to each element and the result returned
  as an array.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

asinh

SYNOPSIS
  Compute the inverse-sinh of a number

USAGE
  y = asinh (x)

DESCRIPTION
  The `asinh' function computes the inverse hyperbolic sine of a number and
  returns the result.  If its argument is an array, the
  `asinh' function will be applied to each element and the result returned
  as an array.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

atan

SYNOPSIS
  Compute the arc-tangent of a number

USAGE
  y = atan (x)

DESCRIPTION
  The `atan' function computes the arc-tangent of a number and
  returns the result.  If its argument is an array, the
  `atan' function will be applied to each element and the result returned
  as an array.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

ceil

SYNOPSIS
  Round x up to the nearest integral value

USAGE
  y = ceil (x)

DESCRIPTION
  This function rounds its numeric argument up to the nearest integral
  value. If the argument is an array, the corresponding array will be
  returned.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

cosh

SYNOPSIS
  Compute the hyperbolic cosine of a number

USAGE
  y = cosh (x)

DESCRIPTION
  The `cosh' function computes the hyperbolic cosine of a number and
  returns the result.  If its argument is an array, the
  `cosh' function will be applied to each element and the result returned
  as an array.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

_diff

SYNOPSIS
  Compute the absolute difference of two values

USAGE
  y = _diff (x, y)

DESCRIPTION
  The `_diff' function returns a floating point number equal to
  the absolute value of the difference of its two arguments.
  If either argument is an array, an array of the corresponding values
  will be returned.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

log1p

SYNOPSIS
  Compute the logarithm of 1 plus a number

USAGE
  y = log1p (x)

DESCRIPTION
  The `log1p' function computes the natural logarithm of 1.0 plus
  `x' returns the result.  If its argument is an array, the
  `log1p' function will be applied to each element and the results
  returned as an array.

This function should be used instead of `log(1+x)' to avoid
  numerical errors whenever `x' is close to 0.

SEE ALSO
  log, expm1, cos, atan, acosh, cosh

--------------------------------------------------------------

_max

SYNOPSIS
  Compute the maximum of two or more numeric values

USAGE
  z = _max (x1,...,xN)

DESCRIPTION
  The `_max' function returns a floating point number equal to
  the maximum value of its arguments.  If any of the argiments are
  arrays (of equal length), an array of the corresponding values will
  be returned.

NOTES
  This function returns a floating point result even when the
  arguments are integers.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

sinh

SYNOPSIS
  Compute the hyperbolic sine of a number

USAGE
  y = sinh (x)

DESCRIPTION
  The `sinh' function computes the hyperbolic sine of a number and
  returns the result.  If its argument is an array, the
  `sinh' function will be applied to each element and the result returned
  as an array.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

sqr

SYNOPSIS
  Compute the square of a number

USAGE
  y = sqr(x)

DESCRIPTION
  The `sqr' function returns the square of an arithmetic type.  If its
  argument is a complex number (Complex_Type), then it returns
  the square of the modulus.  If the argument is an array, a new array
  will be created whose elements are obtained from the original array
  by using the `sqr' function.

NOTES
  For real scalar numbers, using `x*x' instead of `sqr(x)'
  will result in faster executing code.  However, if `x' is an
  array, then `sqr(x)' will execute faster.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

tanh

SYNOPSIS
  Compute the hyperbolic tangent of a number

USAGE
  y = tanh (x)

DESCRIPTION
  The `tanh' function computes the hyperbolic tangent of a number and
  returns the result.  If its argument is an array, the
  `tanh' function will be applied to each element and the result returned
  as an array.

SEE ALSO
  cos, atan, acosh, cosh

--------------------------------------------------------------

_ispos

SYNOPSIS
  Test if a number is greater than 0

USAGE
  Char_Type _ispos(x)

DESCRIPTION
  This function returns 1 if a number is greater than 0, and zero
  otherwise.  If the argument is an array, then the corresponding
  array of boolean (Char_Type) values will be returned.

SEE ALSO
  stat_file

--------------------------------------------------------------

setgid

SYNOPSIS
  Set the group-id of the current process

USAGE
  Int_Type setgid (Int_Type gid)

DESCRIPTION
  The `setgid' function sets the effective group-id of the current
  process.  It returns zero upon success, or -1 upon error and sets
  `errno' appropriately.

NOTES
  This function is not supported by all systems.

SEE ALSO
  stat_file

--------------------------------------------------------------

uname

SYNOPSIS
  Get the system name

USAGE
  Struct_Type uname ()

DESCRIPTION
  The `uname' function returns a structure containing information
  about the operating system.  The structure contains the following
  fields:

sysname  (Name of the operating system)
       nodename (Name of the node within the network)
       release  (Release level of the OS)
       version  (Current version of the release)
       machine  (Name of the hardware)

NOTES
  Not all systems support this function.