d-f [-n | scale] < doubles > floatsD-F(1)
NAME
d-f - convert double-precision floats to single-precision floats
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SYNOPSIS
DESCRIPTION
d-f reads a stream of machine-native double-precision (8-byte) binary floating point values from standard input, converts each one to a single-precision (4-byte) binary float, and writes the result to standard output.
An optional argument controls scaling. If a numeric scale is given, every value is multiplied by it during the conversion. The -n flag selects normalized output, leaving the unit scale of 1.0 in effect. With no argument the values are converted unchanged.
Because the input and output are raw binary, d-f refuses to run when standard input or standard output is a terminal, and it rejects a scale of zero. The inverse conversion, from single-precision floats back to doubles, is performed by f-d(1).
This command is deprecated and is scheduled for removal; it prints a deprecation warning on startup.
OPTIONS
- -n
-
Normalize the data. The unit scale factor of 1.0 is retained so that data already in the range -1.0 to +1.0 is preserved.
- scale
-
A numeric multiplier applied to every value as it is converted. May not be zero.
EXAMPLES
Example 1. Halve the amplitude of a double stream
d-f 0.5 < signal.d > signal.fReads double-precision samples from signal.d, scales each by one half, and writes single-precision floats to signal.f, producing a more compact file at reduced amplitude.
Example 2. Round-trip through single precision
d-f < values.d | f-d > rounded.dConverts doubles to floats and back again with f-d(1), which is a convenient way to see the precision lost when signal-processing data is stored as single-precision floats by tools such as dconv(1) or dmod(1).
SEE ALSO
brlcad(1), f-d(1), dconv(1), dmod(1)
AUTHOR
BRL-CAD Team
COPYRIGHT
This software is Copyright (c) 1989-2026 by the United States Government as represented by U.S. Army Research Laboratory.
BUG REPORTS
Reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org