A-M baby

Task/Formatted-numeric-output/Eiffel/formatted-numeric-output.e

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+note
+	description : "{
+2 Examples are given.
+The first example uses the standard library's FORMAT_DOUBLE class.
+The second example uses the AEL_PRINTF class from the freely available
+Amalasoft Eiffel Library (AEL).
+
+See additional comments in the code.
+}"
+
+class APPLICATION
+
+inherit
+	AEL_PRINTF -- Optional, see below
+
+create
+	make
+
+feature {NONE} -- Initialization
+
+	make
+			-- Run application.
+		do
+			print_formatted_std (7.125)
+			print_formatted_ael (7.125)
+		end
+
+	--|--------------------------------------------------------------
+
+	print_formatted_std (v: REAL_64)
+			-- Print the value 'v' as a zero-padded string in a fixed
+			-- overall width of 9 places and, with a precision of
+			-- to 3 places to the right of the decimal point.
+			-- Use the FORMAT_DOUBLE class from the standard library
+		local
+			fmt: FORMAT_DOUBLE
+		do
+			create fmt.make (9, 3)
+			fmt.zero_fill
+			print (fmt.formatted (v) + "%N")
+		end
+
+	--|--------------------------------------------------------------
+
+	print_formatted_ael (v: REAL_64)
+			-- Print the value 'v' as a zero-padded string in a fixed
+			-- overall width of 9 places and, with a precision of
+			-- to 3 places to the right of the decimal point.
+			-- Use the AEL_PRINTF class from the Amalasoft Eiffel Library
+			-- freely available from www.amalasoft.com
+		do
+			-- printf accepts a format string and an argument list
+			-- The argument list is a container (often a manifest
+			-- array) of values corresponding to the type of the format
+			-- specified in the format string argument.
+			-- When only one argument is needed, then there is also the
+			-- option to use just the value, without the container.
+			-- In this example, the line would be:
+			--   printf ("%%09.3f%N", v)
+			-- The more deliberate form is used in the actual example,
+			-- as it is more representative of common usage, when there
+			-- are multiple value arguments.
+
+			printf ("%%09.3f%N", << v >>)
+		end
+
+end