Decode/Encode Integers, Words, and IEE754 Floats

Usage: crackNum value OR binary/hex-pattern
-i N Signed integer of N-bits
-w N Unsigned integer of N-bits
-f fp Floating point format fp
-r rm Rounding mode to use. If not given, Nearest-ties-to-Even.
-h, -? --help print help, with examples
-v --version print version info
Examples:
Encoding:
crackNum -i4 -- -2 -- encode as 4-bit signed integer
crackNum -w4 2 -- encode as 4-bit unsigned integer
crackNum -f3+4 2.5 -- encode as float with 3 bits exponent, 4 bits significand
crackNum -f3+4 2.5 -rRTZ -- encode as above, but use RTZ rounding mode.
crackNum -fbp 2.5 -- encode as a brain-precision float
crackNum -fdp 2.5 -- encode as a double-precision float
Decoding:
crackNum -i4 0b0110 -- decode as 4-bit signed integer, from binary
crackNum -w4 0xE -- decode as 4-bit unsigned integer, from hex
crackNum -f3+4 0b0111001 -- decode as float with 3 bits exponent, 4 bits significand
crackNum -fbp 0x000F -- decode as a brain-precision float
crackNum -fdp 0x8000000000000000 -- decode as a double-precision float
Notes:
- For encoding:
- Use -- to separate your argument if it's a negative number.
- For floats: You can pass in NaN, Inf, -0, -Inf etc as the argument, along with a decimal float.
- For decoding:
- Use hexadecimal (0x) or binary (0b) as input. Input must have one of these prefixes.
- You can use _,- or space as a digit to improve readability for the pattern to be decoded
VIM users: You can use the https://github.com/LeventErkok/crackNum/blob/master/crackNum.vim file to
use CrackNum directly from VIM. Simply locate your cursor on the text to crack, and use the
command :CrackNum options
.
Example: Encode a decimal numer as a single-precision IEEE754 number
$ crackNum -fsp -- -2.3e6
Satisfiable. Model:
ENCODED = -2300000.0 :: Float
3 2 1 0
1 09876543 21098765432109876543210
S ---E8--- ----------S23----------
Binary layout: 1 10010100 00011000110000110000000
Hex layout: CA0C 6180
Precision: Single
Sign: Negative
Exponent: 21 (Stored: 148, Bias: 127)
Classification: FP_NORMAL
Binary: -0b1.0001100011000011p+21
Octal: -0o1.061414p+21
Decimal: -2300000.0
Hex: -0x2.3186p+20
Rounding mode: RNE: Round nearest ties to even.
Example: Decode a double-precision IEEE754 number from memory-layout
$ crackNum -fdp 0xfc00 abc1 7F80 0001
Satisfiable. Model:
DECODED = -2.0307920360962302e289 :: Double
6 5 4 3 2 1 0
3 21098765432 1098765432109876543210987654321098765432109876543210
S ----E11---- ------------------------S52-------------------------
Binary layout: 1 11111000000 0000101010111100000101111111100000000000000000000001
Hex layout: FC00 ABC1 7F80 0001
Precision: Double
Sign: Negative
Exponent: 961 (Stored: 1984, Bias: 1023)
Classification: FP_NORMAL
Binary: -0b1.0000101010111100000101111111100000000000000000000001p+961
Octal: -0o2.05274057740000001p+960
Decimal: -2.0307920360962302e289
Hex: -0x2.15782FF000002p+960
Example: Encode an integer as a 7-bit signed word
$ crackNum -i7 12
Satisfiable. Model:
ENCODED = 12 :: IntN 7
654 3210
Binary layout: 000 1100
Hex layout: 0C
Type: Signed 7-bit 2's complement integer
Sign: Positive
Binary: 0b1100
Octal: 0o14
Decimal: 12
Hex: 0xc