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## Re: "fread" help

**From**: |
Hamish Allan |

**Subject**: |
Re: "fread" help |

**Date**: |
Mon, 25 Apr 2005 06:58:15 -0500 |

Hi Ivan,
Your file contents are the string "1,2,3,4,5".
In ASCII this is the bytecodes 0x312c322c 0x332c342c 0x350a

`You are then asking fread() to read in that string as integers. Each
``integer is 4 bytes long, so it can only read 2 of them.
`

`A subsequent call to fread() picks up on the position in the file where
``the last fread() left off, so it still can't read any more.
`

`You might want to have a look at fscanf(), or if you have control over
``the way the numbers are formatted in the file, it's probably best to
``use "load" (try "a = [1 2 3 4 5]; save a").
`
Best wishes,
Hamish
On Apr 25, 2005, at 3:51, ivan wrote:

Hi,
I am a newhand to the Octave. I saw from the document that the built-in
function "fread" can read data from file. And I bulit a data file named
decimal.txt . The file contents are 1,2,3,4,5 .
I type the following command under Octave:
octave:11> index=fopen("decimal.txt")
index =
{
id = 3
name = decimal.txt
mode = r
arch = native
status = 1
}
octave:12> [data,count]=fread(index,5,"int")
data =
171051569
171182643
count = 2
octave:13> [data,count]=fread(index,5,"int")
data =
0
0
0
0
0
count = 0
Obviously the result is different from that I imagine.
The first question of mine is why the first time "fread" get such
resulst ? If I have wrongly used the arguments of the function ?
The second question of mine is why the two times result are different ?
I will appreciate for your help and advice !
Thanks !
B/R
Ivan
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Octave is freely available under the terms of the GNU GPL.
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**"fread" help**, *ivan*, `2005/04/24`
**Re: "fread" help**,
*Hamish Allan* **<=**
*Message not available*