Talk:Decimal32 floating-point format

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What implementations are there of this format?

Concerns about this page

The IEEE 754 standard goes to great lengths to separate the representation of the valid set of numbers in (say) decimal32 from the encoding of interchange formats (a particular representation in a string of binary bits), yet this article seems to muddle the concepts. Might it be better to follow the way it is described in the standard (clause 3)?

There are other problems too: 0.000000×10^−95 to 9.999999×10^96 is not the full range of the format in any sense; also (to be pedantic) the name of the format, in the standard, starts with a lower-case d.

mfc (talk) 17:41, 30 December 2009 (UTC)[reply]

Combination field bit naming

Why are the bits of the combination field named m0 to m5? They are not a mantissa, c0 to c5 would make more sense. — Preceding unsigned comment added by 88.219.179.99 (talk) 10:29, 14 March 2021 (UTC)[reply]

Inconsistent/erroneous claims

"Encoding of the Combination Field" (1) contradicts what is said later under "Binary integer significand field" (2).

In (1) some bits are said to be part of the significand, that are said to be part of the exponent in (2).

A simple example: From "Encoding of the Combination Field" (1)

m4 	m3 	m2 	m1 	m0 	Exponent 	Significand
0 	0 	a 	b 	c 	00 	        0abc

From "Binary integer significand field" (2)

s 00eeeeee   (0)ttt tttttttttt tttttttttt

Since the combination field is preceded by a sign bit, (1) can be rewritten to:

s m4 m3 m2 m1 m0

Comparing the last two fixed-width font lines it must hold that:

m4 = 0, m3 = 0, m2 = e5, m1 = e4, m0 = e3

But from (1) we know that:

m2 = a, m1 = b, m0 = c

Which means:

m2 = e5 but also m2 = a

m1 = e4 but also m1 = b

m0 = e3 but also m0 = c

In other words m2, m1, m0 are said to be part of the significand in (1) but also part of the exponent in (2). This obviously cannot be true.

— Preceding unsigned comment added by 88.219.179.99 (talk) 12:24, 14 March 2021 (UTC)[reply]