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------------------------------------------------------------------------
-- ddLogB.decTest -- integral 754r adjusted exponent, for decDoubles --
-- Copyright (c) IBM Corporation, 2005, 2008. All rights reserved. --
------------------------------------------------------------------------
-- Please see the document "General Decimal Arithmetic Testcases" --
-- at http://www2.hursley.ibm.com/decimal for the description of --
-- these testcases. --
-- --
-- These testcases are experimental ('beta' versions), and they --
-- may contain errors. They are offered on an as-is basis. In --
-- particular, achieving the same results as the tests here is not --
-- a guarantee that an implementation complies with any Standard --
-- or specification. The tests are not exhaustive. --
-- --
-- Please send comments, suggestions, and corrections to the author: --
-- Mike Cowlishaw, IBM Fellow --
-- IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK --
-- mfc@uk.ibm.com --
------------------------------------------------------------------------
version: 2.58
precision: 16
maxExponent: 384
minExponent: -383
extended: 1
clamp: 1
rounding: half_even
-- basics
ddlogb000 logb 0 -> -Infinity Division_by_zero
ddlogb001 logb 1E-398 -> -398
ddlogb002 logb 1E-383 -> -383
ddlogb003 logb 0.001 -> -3
ddlogb004 logb 0.03 -> -2
ddlogb005 logb 1 -> 0
ddlogb006 logb 2 -> 0
ddlogb007 logb 2.5 -> 0
ddlogb008 logb 2.500 -> 0
ddlogb009 logb 10 -> 1
ddlogb010 logb 70 -> 1
ddlogb011 logb 100 -> 2
ddlogb012 logb 333 -> 2
ddlogb013 logb 9E+384 -> 384
ddlogb014 logb +Infinity -> Infinity
-- negatives appear to be treated as positives
ddlogb021 logb -0 -> -Infinity Division_by_zero
ddlogb022 logb -1E-398 -> -398
ddlogb023 logb -9E-383 -> -383
ddlogb024 logb -0.001 -> -3
ddlogb025 logb -1 -> 0
ddlogb026 logb -2 -> 0
ddlogb027 logb -10 -> 1
ddlogb028 logb -70 -> 1
ddlogb029 logb -100 -> 2
ddlogb030 logb -9E+384 -> 384
ddlogb031 logb -Infinity -> Infinity
-- zeros
ddlogb111 logb 0 -> -Infinity Division_by_zero
ddlogb112 logb -0 -> -Infinity Division_by_zero
ddlogb113 logb 0E+4 -> -Infinity Division_by_zero
ddlogb114 logb -0E+4 -> -Infinity Division_by_zero
ddlogb115 logb 0.0000 -> -Infinity Division_by_zero
ddlogb116 logb -0.0000 -> -Infinity Division_by_zero
ddlogb117 logb 0E-141 -> -Infinity Division_by_zero
ddlogb118 logb -0E-141 -> -Infinity Division_by_zero
-- full coefficients, alternating bits
ddlogb121 logb 268268268 -> 8
ddlogb122 logb -268268268 -> 8
ddlogb123 logb 134134134 -> 8
ddlogb124 logb -134134134 -> 8
-- Nmax, Nmin, Ntiny
ddlogb131 logb 9.999999999999999E+384 -> 384
ddlogb132 logb 1E-383 -> -383
ddlogb133 logb 1.000000000000000E-383 -> -383
ddlogb134 logb 1E-398 -> -398
ddlogb135 logb -1E-398 -> -398
ddlogb136 logb -1.000000000000000E-383 -> -383
ddlogb137 logb -1E-383 -> -383
ddlogb138 logb -9.999999999999999E+384 -> 384
-- ones
ddlogb0061 logb 1 -> 0
ddlogb0062 logb 1.0 -> 0
ddlogb0063 logb 1.000000000000000 -> 0
-- notable cases -- exact powers of 10
ddlogb1100 logb 1 -> 0
ddlogb1101 logb 10 -> 1
ddlogb1102 logb 100 -> 2
ddlogb1103 logb 1000 -> 3
ddlogb1104 logb 10000 -> 4
ddlogb1105 logb 100000 -> 5
ddlogb1106 logb 1000000 -> 6
ddlogb1107 logb 10000000 -> 7
ddlogb1108 logb 100000000 -> 8
ddlogb1109 logb 1000000000 -> 9
ddlogb1110 logb 10000000000 -> 10
ddlogb1111 logb 100000000000 -> 11
ddlogb1112 logb 1000000000000 -> 12
ddlogb1113 logb 0.00000000001 -> -11
ddlogb1114 logb 0.0000000001 -> -10
ddlogb1115 logb 0.000000001 -> -9
ddlogb1116 logb 0.00000001 -> -8
ddlogb1117 logb 0.0000001 -> -7
ddlogb1118 logb 0.000001 -> -6
ddlogb1119 logb 0.00001 -> -5
ddlogb1120 logb 0.0001 -> -4
ddlogb1121 logb 0.001 -> -3
ddlogb1122 logb 0.01 -> -2
ddlogb1123 logb 0.1 -> -1
ddlogb1124 logb 1E-99 -> -99
ddlogb1125 logb 1E-100 -> -100
ddlogb1127 logb 1E-299 -> -299
ddlogb1126 logb 1E-383 -> -383
-- suggestions from Ilan Nehama
ddlogb1400 logb 10E-3 -> -2
ddlogb1401 logb 10E-2 -> -1
ddlogb1402 logb 100E-2 -> 0
ddlogb1403 logb 1000E-2 -> 1
ddlogb1404 logb 10000E-2 -> 2
ddlogb1405 logb 10E-1 -> 0
ddlogb1406 logb 100E-1 -> 1
ddlogb1407 logb 1000E-1 -> 2
ddlogb1408 logb 10000E-1 -> 3
ddlogb1409 logb 10E0 -> 1
ddlogb1410 logb 100E0 -> 2
ddlogb1411 logb 1000E0 -> 3
ddlogb1412 logb 10000E0 -> 4
ddlogb1413 logb 10E1 -> 2
ddlogb1414 logb 100E1 -> 3
ddlogb1415 logb 1000E1 -> 4
ddlogb1416 logb 10000E1 -> 5
ddlogb1417 logb 10E2 -> 3
ddlogb1418 logb 100E2 -> 4
ddlogb1419 logb 1000E2 -> 5
ddlogb1420 logb 10000E2 -> 6
-- special values
ddlogb820 logb Infinity -> Infinity
ddlogb821 logb 0 -> -Infinity Division_by_zero
ddlogb822 logb NaN -> NaN
ddlogb823 logb sNaN -> NaN Invalid_operation
-- propagating NaNs
ddlogb824 logb sNaN123 -> NaN123 Invalid_operation
ddlogb825 logb -sNaN321 -> -NaN321 Invalid_operation
ddlogb826 logb NaN456 -> NaN456
ddlogb827 logb -NaN654 -> -NaN654
ddlogb828 logb NaN1 -> NaN1
-- Null test
ddlogb900 logb # -> NaN Invalid_operation
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