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islong

Returns True if input is of type long.

Prototype

	function islong (
		arg 
	)
	return_val [1] : logical

Arguments

A variable of any type and dimensionality.

Description

If the input is of type long, then islong will return a single scalar value of True, and False otherwise. If arg is not a valid variable, an error message will be printed.

See Also

Logical functions:
isbyte, ischar, isdouble, isenumeric, isfile, isfloat, isgraphic, isint, isint64, isinteger, islogical, isnumeric, isshort, issnumeric, isstring, isubyte, isuint, isuint64, isulong, isushort, isunsigned

Conversion functions:
tobyte, tochar, todouble, tofloat, toint, toint64, tointeger, tolong, toshort, tosigned, tostring, toubyte, touint, touint64, toulong, tounsigned, toushort

Other useful functions:
typeof, sizeof, ismissing, default_fillvalue, set_default_fillvalue

Examples

The examples below show various ways you can create an NCL variable and how to use the isxxxx functions to test their types.

The "numeric, enumeric, and snumeric" types are special and cannot be created.

• numeric - includes all variables of type byte, short, integer, long, float, and double
• enumeric - includes all variables of type ubyte, ushort, uint, ulong, int64, uint64
• snumeric - includes all numeric and enumeric types

Example 1a

You can create a variable by assigning a value to it. The example below causes NCL to use automatic type assignment:

 i = 38 ; integer
 xscalar = 10000. ; float
 x1d = (/1.,2.,3./) ; float
 str = "This is a string" ; string
 IS_DONE = False ; logical
;---These are all False
 print(isbyte(i))
 print(isunsigned(i))
 print(ischar(str))
 print(isnumeric(str))
 print(islogical(IS_DONE))
;---These are all True
 print(isfloat(xscalar))
 print(isfloat(x1d))
 print(issigned(i))
 print(isstring(str))
 print(isnumeric(i))

Example 1b

You can force a variable to be a specific type by using a literal character:

 b = 10b ; byte
 ub = 100B ; unsigned byte
 l1d = (/10,100,10000l/) ; long
 L1d = (/10000,100000L/) ; ulong
 i64 =わ 4611686018427387904q ; int64
 ui64 =わ 9223372036854775808Q ; uint64
;---These are all True
 print(isbyte(b))
 print(isubyte(ub))
 print(isulong(L1d))
 print(isenumeric(ub))
 print(issnumeric(ub))
 print(isint64(i64))
;---These are all False
 print(isunsigned(b))
 print(ischar(b))
 print(isnumeric(ub))
 print(isint64(ui64))

Example 1c

You can use the special new command to create a variable without having to assign values:

 b = new(1,byte) ; scalar byte
 s = new(1,string) ; single string
 d = new(10,double,"No_FillValue") ; array of doubles
 
 ntim = 10
 nlat = 64
 nlon = 128
 x3d = new((/ntim,nlat,nlon/),double) ; 3D array of doubles
;---These are all False
 print(isuint(b))
 print(ischar(s))
 print(isfloat(d))
;---These are all True
 print(isnumeric(x3d))
 print(isdouble(x3d))

Example 2

Every print statement below should print True:

 b = new(1,byte)
 c = new(1,character)
 d = 10000.d ; The "d" at the end forces a double variable
 fl = 1.0
 fi = addfile("testfile.nc","c")
 g = new(1,graphic)
 i = 20
 is_unlim = (/True,False,False/)
 l2 = new(1,long)
 sh = new(1,short)
 st = "This is a string"
 i64 = 50000q ; int64
;---Unsigned types
 ub = 20B ; ubyte
 us = 50H ; ushort
 ui = 500J ; uint
 ul = 5000L ; ulong
 ui64 = 500000Q ; uint64
 print(isbyte(b))
 print(ischar(c))
 print(isdouble(d))
 print(isfloat(fl))
 print(isfile(fi))
 print(isgraphic(g))
 print(isinteger(i))
 print(islogical(is_unlim))
 print(islong(l2))
 print(isshort(sh))
 print(isstring(st))
 print(isint64(i64))
 print(isuint64(ui64))
 print(isulong(ul))
 print(isuint(ui))
 print(isushort(us))
 print(isnumeric(b))
 print(isnumeric(sh))
 print(isnumeric(i))
 print(isnumeric(l2))
 print(isnumeric(fl))
 print(isnumeric(d))
 print(isenumeric(us))
 print(isenumeric(ui))
 print(isenumeric(ul))
 print(isenumeric(i64))
 print(isenumeric(ui64))
 print(issnumeric(us))
 print(issnumeric(ui))
 print(issnumeric(ul))
 print(issnumeric(i64))
 print(issnumeric(ui64))