New bytecalc-function (for PB 4.01+)

[AND51]

Hello!

Here's my new bytecalc() function for PB 4.01+. (Don't try to beat this, the german-forum-competition is over and I've won).

This procedure turns a quad number of bytes into the greatest unit.
Eample:
1024 Byte => 1 KB
16777216 => 16 MB.

You can optionally switch on decimals numbers; the procedure automatically enforces no decimal numbers, if the greatest unit is "Byte", because it doesn't make sense to have 3.67 Byte, does it?

Code: Select all

Procedure.s bytecalc(byte.q, NbDecimals.b=0)
	Protected unit.b=Round(Log(byte)/Log(1024), 0)
	ProcedureReturn StrD(byte/Pow(1024, unit), NbDecimals*(unit And 1))+" "+StringField("Byte,KB,MB,GB,TB,PB,EB", unit+1, ",")
EndProcedure

Debug bytecalc(FileSize("C:\pagefile.sys"))
Debug bytecalc(3.67*1024)
Debug bytecalc($FFFFFF)
Debug bytecalc(1024)

Do you think, this code can be added to PB as a "native function"?

[Trond]

Basically taking bytes as a quad is no use because you're converting to a double inside the function.

[Flype]

hi,

and what about this one ?

Code: Select all

Import "shlwapi.lib"
  CompilerIf #PB_Compiler_Unicode
  bytecalc_(number.q, *buffer, length.l) As "_StrFormatByteSizeW@16"
  CompilerElse
  bytecalc_(number.q, *buffer, length.l) As "_StrFormatByteSize64A@16"
  CompilerEndIf
EndImport

Macro bytecalc(num, lbuf = 255)
  PeekS(bytecalc_(num, @buf.s{lbuf}, lbuf), lbuf)
EndMacro


For i = 0 To 62
  Debug bytecalc(Pow(2, i))
Next

yes but i must admit it is not cross-platform !

but just one question :
what the hell means the 'P'b and 'E'b ?

Kb -> Kilo Bytes
Mb -> Mega Bytes
Gb -> Giga Bytes
Tb -> Tera Bytes
Pb -> ?
Eb -> ?

[Flype]

ah yes - i found it !

it is :

Pb -> Peta Bytes

Eb -> Exa Bytes

you can verify it on wikipedia :
http://en.wikipedia.org/wiki/SI_prefix

[AND51]

Basically taking bytes as a quad is no use because you're converting to a double inside the function.

Yes, because the user might want to have decimal numbers; this couldn't be realized with not using doubles.


@ flype: I've no knowlege about the import-function, so I cannot comment your solution. However, it seems to work, I tested it.

[Rescator]

http://en.wikipedia.org/wiki/Binary_prefix

I would recommend following the IEC standard prefixes instead to avoid confusion with the SI prefixes.

[thamarok]

ah yes - i found it !

it is :

Pb -> Peta Bytes

Eb -> Exa Bytes

you can verify it on wikipedia :
http://en.wikipedia.org/wiki/SI_prefix

No, Pb is PureBasic

[Trond]

Basically taking bytes as a quad is no use because you're converting to a double inside the function.

Yes, because the user might want to have decimal numbers; this couldn't be realized with not using doubles.

But then you can't take a byte count that is as large as a quad.

[AND51]

Basically taking bytes as a quad is no use because you're converting to a double inside the function.

Yes, because the user might want to have decimal numbers; this couldn't be realized with not using doubles.

But then you can't take a byte count that is as large as a quad.

Correct, but this procedure hs been designed for programs for home PCs. ´has your PC files that are larger than 1 TB? I don't think so. So you can use my procedure without worries.

Even if you want the full power, then use flype's procedure.

[Dare]

http://en.wikipedia.org/wiki/Binary_prefix

I would recommend following the IEC standard prefixes instead to avoid confusion with the SI prefixes.

Read it - got confused.

Does it mean that 1Kb = 1000 and 1KiB = 1024 (the real K!)? And what is a Ko (apart from a knock out)?

[AND51]

I won't use KiB, MiB, GiB, etc. it's just confusing.

[GeoTrail]

http://en.wikipedia.org/wiki/Binary_prefix

I would recommend following the IEC standard prefixes instead to avoid confusion with the SI prefixes.

Read it - got confused.

Does it mean that 1Kb = 1000 and 1KiB = 1024 (the real K!)? And what is a Ko (apart from a knock out)?

Although computer data is normally measured in binary code, the prefixes for the multiples are based on the metric system. The nearest binary number to 1,000 is 2^10 or 1,024; thus 1,024 bytes was named a Kilobyte. So, although a metric "kilo" equals 1,000 (e.g. one kilogram = 1,000 grams), a binary "Kilo" equals 1,024 (e.g. one Kilobyte = 1,024 bytes). Not surprisingly, this has led to a great deal of confusion.

[stubbsi]

pariticularly when the EU got involved and decided that a kb was 1000 bytes not 1024.

logical - eh!! bureaucracy gone mad - obviously don't know that 2^10 = 1024.

[Rescator]

As long as you remain consistent within your program (i.e. do NOT mix KB and KiB etc.) then most users wont mind whether you use KB or KiB. It might be a nice touch to mention in the user documentation for your programs whether KB indicate KB or KiB though.
By users I here mean end users, as a programmer (PB user) I sure hope we know/see the difference what is KB or KiB

[Dare]

Hi GeoTrail, stubbsi and Rescator,

Thanks. So officially a KiB = 1024?

And a Ko is .. what?

lol. Bring back feet and inches and tons and gallons and furlongs! And shillings and pence for that matter! (This program is 27 acres zipped and requires 132 acres of diskspace when decompressed. It costs 8 pounds seven shillings and sixpence - download now?)