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Float ? 4bytes string.. pls help me :( #147821 24/04/06 05:42 PM
Joined: Jul 2005 Posts: 40 K Karas OP Ameglian cow
OP Karas Ameglian cow K Joined: Jul 2005 Posts: 40	Hi guys, i have this binvar: 254 255 255 255 78 190 58 67 that must be: -2 how can i traslate this to -2 ? O_o Thx j0k3r @ k4s.ch

Re: Float ? 4bytes string.. pls help me :( #147822 24/04/06 08:07 PM
Joined: Sep 2005 Posts: 116 Amersfoort I Im2good4u Vogon poet
Im2good4u Vogon poet I Joined: Sep 2005 Posts: 116 Amersfoort	hmm depents on wut charecter type is used ? i tink its 32 bits charecters i dunno u ned some kind of charecter table to lok it up

Re: Float ? 4bytes string.. pls help me :( #147823 24/04/06 10:16 PM
Joined: Jul 2005 Posts: 40 K Karas OP Ameglian cow
OP Karas Ameglian cow K Joined: Jul 2005 Posts: 40	that's not the problem (to view a character simply use $chr(num) ) 254 255 255 255 78 190 58 67 ---> þÿÿÿN¾:C Dump: index char byte 132 --> þ --> 254 133 --> ÿ --> 255 134 --> ÿ --> 255 135 --> ÿ --> 255 136 --> N --> 78 137 --> ¾ --> 190 138 --> : --> 58 139 --> C --> 67 The problem is that the 8 bytes represent the value -2 .. or I think so.. j0k3r @ k4s.ch

Re: Float ? 4bytes string.. pls help me :( #147824 24/04/06 10:18 PM
Joined: Sep 2005 Posts: 2,881 H hixxy Hoopy frood
hixxy Hoopy frood H Joined: Sep 2005 Posts: 2,881	What makes you think it represents -2?

Re: Float ? 4bytes string.. pls help me :( #147825 25/04/06 02:06 AM
Joined: Sep 2003 Posts: 4,230 D DaveC Hoopy frood
DaveC Hoopy frood D Joined: Sep 2003 Posts: 4,230	The 254 255 255 255 is -2 the following 78 190 58 67 could be anything at all, i doubt it directly relates to the same thing. the 254 255 255 255 is a 32bit signed integer using LSB to MSB (least to most significanat byte order "small ended") If you break it down as follows byteA = 254 byteB = 255 byteC = 255 byteD = 255 the calculation is... var value = $calc((byteA) + (byteB * 256) + (byteC * 65536) + ($and(byteD,127) * 16777216) + (($and(byteD,128) / 128) * -2147483648)) ByteD has its highest bit removed and is multiplied by 16777216 ( 256256256) Following that should the highest bit of ByteD be ON then -2147483648 is added to the total, this essentially is the value of the highest bit (128256256*256) but negitive, this allows for values from -2147483648 to 2147483647

Re: Float ? 4bytes string.. pls help me :( #147826 25/04/06 10:56 AM
Joined: Jul 2005 Posts: 40 K Karas OP Ameglian cow
OP Karas Ameglian cow K Joined: Jul 2005 Posts: 40	Quote: The 254 255 255 255 is -2 the following 78 190 58 67 could be anything at all, i doubt it directly relates to the same thing. the 254 255 255 255 is a 32bit signed integer using LSB to MSB (least to most significanat byte order "small ended") If you break it down as follows byteA = 254 byteB = 255 byteC = 255 byteD = 255 the calculation is... var value = $calc((byteA) + (byteB * 256) + (byteC * 65536) + ($and(byteD,127) * 16777216) + (($and(byteD,128) / 128) * -2147483648)) ByteD has its highest bit removed and is multiplied by 16777216 ( 256256256) Following that should the highest bit of ByteD be ON then -2147483648 is added to the total, this essentially is the value of the highest bit (128256256*256) but negitive, this allows for values from -2147483648 to 2147483647 You are the man ! Thx a lot, it works fine ^_^ j0k3r @ k4s.ch

Re: Float ? 4bytes string.. pls help me :( #147827 25/04/06 03:31 PM
Joined: Sep 2005 Posts: 116 Amersfoort I Im2good4u Vogon poet
Im2good4u Vogon poet I Joined: Sep 2005 Posts: 116 Amersfoort	Dahm how could i have forgotten then :x i had it all at school

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