Commit | Line | Data |
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58d76dfd JH |
1 | #!./perl -w |
2 | # Now they'll be wanting biff! and zap! tests too. | |
3 | ||
4 | BEGIN { | |
5 | chdir 't' if -d 't'; | |
6 | @INC = '../lib'; | |
7 | require './test.pl'; | |
8 | } | |
9 | ||
10 | # This calcualtion ought to be within 0.001 of the right answer. | |
11 | my $bits_in_uv = int (0.001 + log (~0+1) / log 2); | |
12 | ||
13 | # 3**30 < 2**48, don't trust things outside that range on a Cray | |
14 | # Likewise other 3 should not overflow 48 bits if I did my sums right. | |
69ca0fd0 A |
15 | my @pow = ([3,30,1e-14], |
16 | [4,32,0], | |
17 | [5,20,1e-14], | |
18 | [2.5, 10,,1e-14], | |
19 | [-2, 69,0], | |
20 | [-3, 30,0], | |
21 | ); | |
58d76dfd JH |
22 | my $tests; |
23 | $tests += $_->[1] foreach @pow; | |
24 | ||
0615a994 SM |
25 | plan tests => 2 + $bits_in_uv + $tests; |
26 | ||
27 | # This gave positive 27 before change #20167 | |
28 | is((-3)**3, -27, "(negative int) ** (odd power) is negative"); | |
58d76dfd JH |
29 | |
30 | # Ought to be 32, 64, 36 or something like that. | |
31 | ||
32 | my $remainder = $bits_in_uv & 3; | |
33 | ||
34 | cmp_ok ($remainder, '==', 0, 'Sanity check bits in UV calculation') | |
35 | or printf "# ~0 is %d (0x%d) which gives $bits_in_uv bits\n", ~0, ~0; | |
36 | ||
37 | # These are a lot of brute force tests to see how accurate $m ** $n is. | |
38 | # Unfortunately rather a lot of perl programs expect 2 ** $n to be integer | |
39 | # perfect, forgetting that it's a call to floating point pow() which never | |
40 | # claims to deliver perfection. | |
41 | foreach my $n (0..$bits_in_uv - 1) { | |
69ca0fd0 | 42 | my $pow = 2 ** $n; |
58d76dfd | 43 | my $int = 1 << $n; |
69ca0fd0 | 44 | cmp_ok ($pow, '==', $int, "2 ** $n vs 1 << $n"); |
58d76dfd JH |
45 | } |
46 | ||
47 | foreach my $pow (@pow) { | |
48 | my ($base, $max, $range) = @$pow; | |
69ca0fd0 | 49 | my $expect = 1; |
58d76dfd | 50 | foreach my $n (0..$max-1) { |
69ca0fd0 A |
51 | my $got = $base ** $n; |
52 | within ($got, $expect, $range, "$base ** $n got[$got] expect[$expect]"); | |
53 | $expect *= $base; | |
58d76dfd JH |
54 | } |
55 | } |