Two's Complement: Binary -> Integer: 0011 0001 0011 0010 0110 1001 0110 0010 0011 0111 0110 0100 0100 0001 0111 0110 Signed Binary Number in Two's Complement Representation, Converted and Written as a Decimal System Integer (in Base Ten)
Signed binary in two's complement representation 0011 0001 0011 0010 0110 1001 0110 0010 0011 0111 0110 0100 0100 0001 0111 0110(2) converted to an integer in decimal system (in base ten) = ?
1. Is this a positive or a negative number?
In a signed binary in two's complement representation, the first bit (the leftmost) indicates the sign, 1 = negative, 0 = positive.
0011 0001 0011 0010 0110 1001 0110 0010 0011 0111 0110 0100 0100 0001 0111 0110 is the binary representation of a positive integer, on 64 bits (8 Bytes).
2. Get the binary representation in one's complement.
* Run this step only if the number is negative *
Note on binary subtraction rules:
11 - 1 = 10; 10 - 1 = 1; 1 - 0 = 1; 1 - 1 = 0.
Subtract 1 from the initial binary number.
* Not the case - the number is positive *
3. Get the binary representation of the positive (unsigned) number.
* Run this step only if the number is negative *
Flip all the bits of the signed binary in one's complement representation (reverse the digits) - replace the bits set on 1 with 0s and the bits on 0 with 1s:
* Not the case - the number is positive *
4. Map the unsigned binary number's digits versus the corresponding powers of 2 that their place value represent:
263
0 262
0 261
1 260
1 259
0 258
0 257
0 256
1 255
0 254
0 253
1 252
1 251
0 250
0 249
1 248
0 247
0 246
1 245
1 244
0 243
1 242
0 241
0 240
1 239
0 238
1 237
1 236
0 235
0 234
0 233
1 232
0 231
0 230
0 229
1 228
1 227
0 226
1 225
1 224
1 223
0 222
1 221
1 220
0 219
0 218
1 217
0 216
0 215
0 214
1 213
0 212
0 211
0 210
0 29
0 28
1 27
0 26
1 25
1 24
1 23
0 22
1 21
1 20
0
5. Multiply each bit by its corresponding power of 2 and add all the terms up.
0011 0001 0011 0010 0110 1001 0110 0010 0011 0111 0110 0100 0100 0001 0111 0110(2) =
(0 × 263 + 0 × 262 + 1 × 261 + 1 × 260 + 0 × 259 + 0 × 258 + 0 × 257 + 1 × 256 + 0 × 255 + 0 × 254 + 1 × 253 + 1 × 252 + 0 × 251 + 0 × 250 + 1 × 249 + 0 × 248 + 0 × 247 + 1 × 246 + 1 × 245 + 0 × 244 + 1 × 243 + 0 × 242 + 0 × 241 + 1 × 240 + 0 × 239 + 1 × 238 + 1 × 237 + 0 × 236 + 0 × 235 + 0 × 234 + 1 × 233 + 0 × 232 + 0 × 231 + 0 × 230 + 1 × 229 + 1 × 228 + 0 × 227 + 1 × 226 + 1 × 225 + 1 × 224 + 0 × 223 + 1 × 222 + 1 × 221 + 0 × 220 + 0 × 219 + 1 × 218 + 0 × 217 + 0 × 216 + 0 × 215 + 1 × 214 + 0 × 213 + 0 × 212 + 0 × 211 + 0 × 210 + 0 × 29 + 1 × 28 + 0 × 27 + 1 × 26 + 1 × 25 + 1 × 24 + 0 × 23 + 1 × 22 + 1 × 21 + 0 × 20)(10) =
(0 + 0 + 2 305 843 009 213 693 952 + 1 152 921 504 606 846 976 + 0 + 0 + 0 + 72 057 594 037 927 936 + 0 + 0 + 9 007 199 254 740 992 + 4 503 599 627 370 496 + 0 + 0 + 562 949 953 421 312 + 0 + 0 + 70 368 744 177 664 + 35 184 372 088 832 + 0 + 8 796 093 022 208 + 0 + 0 + 1 099 511 627 776 + 0 + 274 877 906 944 + 137 438 953 472 + 0 + 0 + 0 + 8 589 934 592 + 0 + 0 + 0 + 536 870 912 + 268 435 456 + 0 + 67 108 864 + 33 554 432 + 16 777 216 + 0 + 4 194 304 + 2 097 152 + 0 + 0 + 262 144 + 0 + 0 + 0 + 16 384 + 0 + 0 + 0 + 0 + 0 + 256 + 0 + 64 + 32 + 16 + 0 + 4 + 2 + 0)(10) =
(2 305 843 009 213 693 952 + 1 152 921 504 606 846 976 + 72 057 594 037 927 936 + 9 007 199 254 740 992 + 4 503 599 627 370 496 + 562 949 953 421 312 + 70 368 744 177 664 + 35 184 372 088 832 + 8 796 093 022 208 + 1 099 511 627 776 + 274 877 906 944 + 137 438 953 472 + 8 589 934 592 + 536 870 912 + 268 435 456 + 67 108 864 + 33 554 432 + 16 777 216 + 4 194 304 + 2 097 152 + 262 144 + 16 384 + 256 + 64 + 32 + 16 + 4 + 2)(10) =
3 545 011 727 251 030 390(10)
5. If needed, adjust the sign of the integer number by the first digit (leftmost) of the signed binary:
0011 0001 0011 0010 0110 1001 0110 0010 0011 0111 0110 0100 0100 0001 0111 0110(2) = 3 545 011 727 251 030 390(10)
The signed binary number in two's complement representation 0011 0001 0011 0010 0110 1001 0110 0010 0011 0111 0110 0100 0100 0001 0111 0110(2) converted and written as an integer in decimal system (base ten):
0011 0001 0011 0010 0110 1001 0110 0010 0011 0111 0110 0100 0100 0001 0111 0110(2) = 3 545 011 727 251 030 390(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.
Convert signed binary numbers in two's complement representation to decimal system (base ten) integers
Binary number's length must be: 2, 4, 8, 16, 32, 64 - or else extra bits on 0 are added in front (to the left).
How to convert a signed binary number in two's complement representation to an integer in base ten:
1) In a signed binary two's complement, first bit (leftmost) indicates the sign, 1 = negative, 0 = positive.
2) Get the signed binary representation in one's complement, subtract 1 from the initial number.
3) Construct the unsigned binary number: flip all the bits in the signed binary one's complement representation (reversing the digits) - replace the bits set on 1 with 0s and the bits on 0 with 1s.
4) Multiply each bit of the binary number by its corresponding power of 2 that its place value represents.
5) Add all the terms up to get the positive integer number in base ten.
6) Adjust the sign of the integer number by the first bit of the initial binary number.