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isscalar

Returns True if the given argument is a scalar (rank one and size one).

Available in version 6.4.0 and later.

Prototype

	function isscalar (
		x       
	)

Arguments

x

A variable of any type.

Return value

Returns True if x is a scalar; False otherwise.

Description

In mathematics, a 'scalar' refers to a variable (x) of type numeric that has an array rank and size of one. This implementation adopts a broader definition. Here a scalar is defined as "an atomic quantity that can hold only one value at a time".

If a user wishes to restrict the test to type numeric, the following approach could be used:


        if (isnumeric(x) .and. isscalar(x)) then
            ...
        end if

or a user defined function could be created:

        undef("isscalar_num")
        function isscalar_num (x)
        begin
          if (isnumeric(x) .and. isscalar(x)) then
              return(True)
          else
              return(False)
          end if
        end
     

Examples

Example 1

       i = 1
       x = (/ 3.3, 7.3111 /)
       s = "s"
       S = (/ "a", "q", "z"/)

       print("isscalar(i)="+isscalar(i))
       print("isscalar(x)="+isscalar(x))
       print("isscalar(s)="+isscalar(s))
       print("isscalar(S)="+isscalar(S))
yields
     

(0)    isscalar(i)=True
(0)    isscalar(x)=False
(0)    isscalar(s)=True
(0)    isscalar(S)=False