Hi all,
I am getting following output by using commands like sort, uniq and awk to the standard output.
110 d
40 a
59 c
9 b
3 e
Now at the end I would like to add all the numbers in column 1 and display the count of all numbers i.e. (110 + 40 + 59 + 9 + 3).
Also the output may... (3 Replies)
Hi Everyone:
My shell script creates multiple csv files (~30) in for loop. I want to compile (or merge) 3rd column from each (all) of these files to another file (in loop). Please help. Thanks. (3 Replies)
Hi
I have a file with 3 columns. say,
infile:
1 50 68
34 3 23
23 4 56
-------
-------
I want to generate n files from this file using a loop so that 1st column in output file is (column1 of infile/(2*n+2.561))
I am doing like this:
for ((i=1; i<=3; i++))
do
a=`echo... (3 Replies)
Hello,
I have a file with 32 columns and I want to print one column at a time, and then read each line of this column in order to use grep command.
I tried with awk but i cannot put variable in awk
for a in {1..32..1};do awk '{print$a}' file1.txt|while read line;do grep $line file2.txt;done >... (5 Replies)
I have two files like this:
fileA.net
A
B
C
fileA.dat
1
2
3
and I want the output
output_expected
A 1
B 2
C 3
I know that the easier way is to do a paste fileA.net fileA.dat, but the problem is that I have 10,000 couple of files (fileB.net with fileB.dat; fileC.net with... (3 Replies)
Hello,
I have a single text file with three columns like:
2 1 10
3 6 11
4 4 12
5 5 13
6 8 14
I was wondering how I can run a shell script to (do loop) to read the first point in the first column , compare it with all the points in the second column and if they are the same,... (12 Replies)
I have 2 files, that look like this:
ID SNP1 SNP2 SNP3 SNP4
A1 1 2 0 2
A2 2 0 1 1
A3 0 2 NA 1
A4 1 1 0 2
and this:
SNP score
SNP1 0.5
SNP2 0.7
SNP3 0.8
SNP4 0.2
Basically, all of the SNP-values are 0,1, 2 or NA, and they each have a score, listed in the second file. The total... (5 Replies)
Hi all,
If i would like to process a file input as below:
col1 col2 col3 ...col100
1 A C E A ...
3 D E G A
5 T T A A
6 D C A G
how can i perform a for loop to count the occurences of letters in each column? (just like uniq -c ) in every column.
on top of that, i would also like... (8 Replies)
Hi, I have a shell script which analyses the log folder for a specific string and throws me the output. I have used for loop since it does this in multiple servers. Now I want to save the output in a excel in the below format. Can someone please help?
The output which I get
Server1 : count... (14 Replies)
Discussion started by: srilaxman
14 Replies
LEARN ABOUT OSX
random
RANDOM(4) BSD Kernel Interfaces Manual RANDOM(4)NAME
random , urandom -- random data source devices.
SYNOPSIS
pseudo-device random
DESCRIPTION
The random device produces uniformly distributed random byte values of potentially high quality.
To obtain random bytes, open /dev/random for reading and read from it.
To add entropy to the random generation system, open /dev/random for writing and write data that you believe to be somehow random.
/dev/urandom is a compatibility nod to Linux. On Linux, /dev/urandom will produce lower quality output if the entropy pool drains, while
/dev/random will prefer to block and wait for additional entropy to be collected. With Yarrow, this choice and distinction is not necessary,
and the two devices behave identically. You may use either.
OPERATION
The random device implements the Yarrow pseudo random number generator algorithm and maintains its entropy pool. Additional entropy is fed
to the generator regularly by the SecurityServer daemon from random jitter measurements of the kernel. SecurityServer is also responsible
for periodically saving some entropy to disk and reloading it during startup to provide entropy in early system operation.
You may feed additional entropy to the generator by writing it to the random device, though this is not required in a normal operating envi-
ronment.
LIMITATIONS AND WARNINGS
Yarrow is a fairly resilient algorithm, and is believed to be resistant to non-root. The quality of its output is however dependent on regu-
lar addition of appropriate entropy. If the SecurityServer system daemon fails for any reason, output quality will suffer over time without
any explicit indication from the random device itself.
Paranoid programmers can counteract this risk somewhat by collecting entropy of their choice (e.g. from keystroke or mouse timings) and seed-
ing it into random directly before obtaining important random numbers.
FILES
/dev/random
/dev/urandom
HISTORY
A random device appeared in the Linux operating system.
Darwin September 6, 2001 Darwin