02-11-2004
for loop with multiple variables ?
I have a script which selects two 'sets' of system LVM device files from a tabular file 'mapfile' using awk :
LIVELV=`awk '{print($1)}' mapfile`
BCVLV=`awk '{print($3)}' mapfile`
I wanted to pass these 'sets' into an LVM command 'loop' along the lines of :
lvmerge $BCVLV $LIVELV
ie. for each device file in column 1 of the file 'mapfile' merge in the device in column 3 of the same line.
I have messed about for hours with a for loop but I don't think this will handle the two different sets of variables in the same statement ?
I am probably approaching this from completely the wrong angle.
Any advice would be gratefully received - scripting isn't my strong suit - but god knows I'm trying !
9 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hi ,
I am trying to write a script in kshell with while loop ,its like
count=1
count_cmp=1
while ; do
tail -$count tempfile | head -1 > tempstring
.......
done
However i get CIF.sh: line 33: '
I have checked thetrailing spaces , not sure what is... (4 Replies)
Discussion started by: amit1_x
4 Replies
2. UNIX for Dummies Questions & Answers
hi,
I want an equivalent for loop for this C code in unix shell script...
for(int i,int j;i<5;i++,j++)
{
}
Please reply soon
Regards
Navjot (1 Reply)
Discussion started by: navjotsingh
1 Replies
3. Shell Programming and Scripting
I'm trying to understand if it's possible to create a set of variables that are numbered based on another variable (using eval) in a loop, and then call on it before the loop ends.
As an example I've written a script called question (The fist command is to show what is the contents of the... (2 Replies)
Discussion started by: DeCoTwc
2 Replies
4. Shell Programming and Scripting
Hi,
I have two variables like below which will always be of the same size
a=1:2:3
b=A:B:C
I need to use a for/while loop that will have both the variables available. I cannot use an array here and will probably might iterate through the variable as echo $a | tr ':' '\n' and thus iterate... (5 Replies)
Discussion started by: Elizabeth H
5 Replies
5. UNIX for Dummies Questions & Answers
Hi,
I need to pass the multiple values of src1 to another variable. I managed to print it but not sure how to assign it to a variable in a loop.
src1=01,02,03
echo $src1|awk 'BEGIN {FS=","} {for(i=1;i<=NF;i++) print $i}'
I need to pass the value as
src2=01
src2=02
src2=03
Thanks... (4 Replies)
Discussion started by: shash
4 Replies
6. UNIX for Dummies Questions & Answers
Hi,
I managed to read and print variable as shown in the below code.
table_name=table1,table2,table3
i=0
IFS=","
for i in $table_name
do
echo $i
done
Is there a way how I can read more than one variable. For example I need to read 2 variables and populate the output... (6 Replies)
Discussion started by: shash
6 Replies
7. Shell Programming and Scripting
hi,
i need a portion in a audit logging shell script where i have to loop thru multiple variables.
I need some help in accomplishing this. i have 3 variables
var1=1,23,234
var2=a,ab,xyz
var3=0,0,0
the variables will have variables number of values but same length.(3 in this case )
i... (10 Replies)
Discussion started by: rock1
10 Replies
8. Shell Programming and Scripting
Hi
My goal is to fill an HTML form and submit.
What I have managed to do:
1. curl command to fill up the form and submit
2. a file which has the input
curl command:
curl -v -b cookie.txt -d __CSRFToken__=dc23d5da47953b3b390ec68d972af10380908b14 -d do=create -d a=open -d... (10 Replies)
Discussion started by: zorrox
10 Replies
9. UNIX for Beginners Questions & Answers
Hi!
I've run into a problem where my variables are displayed in the wrong order. Basically I'm supposed to use a file that has information like this username:firstname:lastname:etc:etc.
What I'm interested in doing is reformating it into a something more like this: username lastname,... (2 Replies)
Discussion started by: reindeermountai
2 Replies
LEARN ABOUT MINIX
ppmquant
ppmquant(1) General Commands Manual ppmquant(1)
NAME
ppmquant - quantize the colors in a portable pixmap down to a specified number
SYNOPSIS
ppmquant [-floyd|-fs] ncolors [ppmfile]
ppmquant [-floyd|-fs] [-nofloyd|-nofs] -mapfile mapfile [ppmfile]
All options can be abbreviated to their shortest unique prefix. You may use two hyphens instead of one to designate an option. You may
use either white space or equals signs between an option name and its value.
DESCRIPTION
pnmquant is a newer, more general program that is backward compatible with ppmquant. ppmquant may be faster, though.
Reads a PPM image as input. Chooses ncolors colors to best represent the image, maps the existing colors to the new ones, and writes a PPM
image as output.
The quantization method is Heckbert's "median cut".
Alternately, you can skip the color-choosing step by specifying your own set of colors with the -mapfile option. The mapfile is just a ppm
file; it can be any shape, all that matters is the colors in it. For instance, to quantize down to the 8-color IBM TTL color set, you
might use:
P3
8 1
255
0 0 0
255 0 0
0 255 0
0 0 255
255 255 0
255 0 255
0 255 255
255 255 255
If you want to quantize one image to use the colors in another one, just use the second one as the mapfile. You don't have to reduce it
down to only one pixel of each color, just use it as is.
If you use a mapfile, the output image has the same maxval as the mapfile. Otherwise, the output maxval is the same as the input maxval,
or less in some cases where the quantization process reduces the necessary resolution.
The -floyd/-fs option enables a Floyd-Steinberg error diffusion step. Floyd-Steinberg gives vastly better results on images where the
unmodified quantization has banding or other artifacts, especially when going to a small number of colors such as the above IBM set. How-
ever, it does take substantially more CPU time, so the default is off.
-nofloyd/-nofs means not to use the Floyd-Steinberg error diffusion. This is the default.
REFERENCES
"Color Image Quantization for Frame Buffer Display" by Paul Heckbert, SIGGRAPH '82 Proceedings, page 297.
SEE ALSO
pnmquant(1), ppmquantall(1), pnmdepth(1), ppmdither(1), ppm(5)
AUTHOR
Copyright (C) 1989, 1991 by Jef Poskanzer.
12 January 1991 ppmquant(1)