File: coreutils.info, Node: seq invocation, Prev: numfmt invocation, Up: Numeric operations 26.3 ‘seq’: Print numeric sequences =================================== ‘seq’ prints a sequence of numbers to standard output. Synopses: seq [OPTION]... LAST seq [OPTION]... FIRST LAST seq [OPTION]... FIRST INCREMENT LAST ‘seq’ prints the numbers from FIRST to LAST by INCREMENT. By default, each number is printed on a separate line. When INCREMENT is not specified, it defaults to ‘1’, even when FIRST is larger than LAST. FIRST also defaults to ‘1’. So ‘seq 1’ prints ‘1’, but ‘seq 0’ and ‘seq 10 5’ produce no output. The sequence of numbers ends when the sum of the current number and INCREMENT would become greater than LAST, so ‘seq 1 10 10’ only produces ‘1’. INCREMENT must not be ‘0’; use the tool ‘yes’ to get repeated output of a constant number. FIRST, INCREMENT and LAST must not be ‘NaN’, but ‘inf’ is supported. Floating-point numbers may be specified in either the current or the C locale. *Note Floating point::. The program accepts the following options. Also see *note Common options::. Options must precede operands. ‘-f FORMAT’ ‘--format=FORMAT’ Print all numbers using FORMAT. FORMAT must contain exactly one of the ‘printf’-style floating point conversion specifications ‘%a’, ‘%e’, ‘%f’, ‘%g’, ‘%A’, ‘%E’, ‘%F’, ‘%G’. The ‘%’ may be followed by zero or more flags taken from the set ‘-+#0 '’, then an optional width containing one or more digits, then an optional precision consisting of a ‘.’ followed by zero or more digits. FORMAT may also contain any number of ‘%%’ conversion specifications. All conversion specifications have the same meaning as with ‘printf’. The default format is derived from FIRST, STEP, and LAST. If these all use a fixed point decimal representation, the default format is ‘%.Pf’, where P is the minimum precision that can represent the output numbers exactly. Otherwise, the default format is ‘%g’. ‘-s STRING’ ‘--separator=STRING’ Separate numbers with STRING; default is a newline. The output always terminates with a newline. ‘-w’ ‘--equal-width’ Print all numbers with the same width, by padding with leading zeros. FIRST, STEP, and LAST should all use a fixed point decimal representation. (To have other kinds of padding, use ‘--format’). You can get finer-grained control over output with ‘-f’: $ seq -f '(%9.2E)' -9e5 1.1e6 1.3e6 (-9.00E+05) ( 2.00E+05) ( 1.30E+06) If you want hexadecimal integer output, you can use ‘printf’ to perform the conversion: $ printf '%x\n' $(seq 1048575 1024 1050623) fffff 1003ff 1007ff For very long lists of numbers, use xargs to avoid system limitations on the length of an argument list: $ seq 1000000 | xargs printf '%x\n' | tail -n 3 f423e f423f f4240 To generate octal output, use the printf ‘%o’ format instead of ‘%x’. On most systems, seq can produce whole-number output for values up to at least 2^{53}. Larger integers are approximated. The details differ depending on your floating-point implementation. *Note Floating point::. A common case is that ‘seq’ works with integers through 2^{64}, and larger integers may not be numerically correct: $ seq 50000000000000000000 2 50000000000000000004 50000000000000000000 50000000000000000000 50000000000000000004 However, note that when limited to non-negative whole numbers, an increment of less than 200, and no format-specifying option, seq can print arbitrarily large numbers. Therefore ‘seq inf’ can be used to generate an infinite sequence of numbers. Be careful when using ‘seq’ with outlandish values: otherwise you may see surprising results, as ‘seq’ uses floating point internally. For example, on the x86 platform, where the internal representation uses a 64-bit fraction, the command: seq 1 0.0000000000000000001 1.0000000000000000009 outputs 1.0000000000000000007 twice and skips 1.0000000000000000008. An exit status of zero indicates success, and a nonzero value indicates failure.