I'd create an array for each of the columns, something like:
But you'd need to modify std_dev to return the value instead of printing it, update the END block, etc.
(I'd give it a go right now, but am having production issues. If you're still fighting it tomorrow, I can tune it up some.)
I have a CSV file that looks like
0,0,0,0,1,0,1,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0
10,11,7,0,4,12,2,3,7,0,11,3,12,4,0,5,5,4,5,0,8,6,12,0,9,3,3,0,2,7,8
19,11,7,0,4,14,16,10,8,2,13,7,15,6,0,76,6,4,10,0,18,10,17,1,11,3,3,0,9,9,8... (7 Replies)
Hi all,
I am new to shell scripting and wanna calculate the mean and standard deviation using shell programming.
I have a file with letters that are repeating and their corresponding duration
a 0.32
a 0.89
aa 0.34
aa 0.23
au 0.012
au 0.26... (4 Replies)
Hi all,
I want to calculate the standard deviation for a column (happens to be column 3).
Does any know of simple awk script to do this?
Thanks (1 Reply)
Hi I want to use awk to print avg and st deviation but it does not go into a file for column 1 only.
I can do average and # of records but i cannot get st deviation.
awk '{sum+=$1} END { print "Average = ",sum/NR}'
thanks (1 Reply)
I have a file with say 50 columns, each containing a whole lot of data.
Each column contains data from a separate simulation, but each simulation is related to the data in the last (REFERENCE) column $50
I need to calculate the RMS deviation for each data line, i.e. column 1 relative to... (12 Replies)
Hi All,
I want someone to modify the below script from this forum so that it can be used for all columns in the file( instead of only printing column 3 mean and standard deviation values). I don't know how to loop around all the columns.
... (3 Replies)
Hi,
I have a file containing 100,000 rows-by-120 columns and I need to compute for the standard deviation for each row. Any idea on how to calculate row-wise standard deviation using awk? My sample data looks like this:
input data:
23 35 12 25 16 17 18 19 29 12
12 26 15 14 15 23 12 12... (2 Replies)
Hello there,
I found an elegant solution to computing average values from multiple text files
awk '{for (i=1;i<=NF;i++){if ($i!~"n/a"){a+=$i}else{b++}}}END{for (i=1;i<=FNR;i++){for (j=1;j<=NF;j++){printf (a/(3-b))((b>0)?"~"b" ":" ")};printf "\n"}}' file1 file2 file3
I tried to modify... (2 Replies)
I have a file that looks that this:
820 890 530
1650 1600 1800
1850 1900 2270
1640 2300 1670
2080 2200 2350
1150 1630 2210
I would like to output the mean and standard deviation of each row so that my final output would look like this
820 890 530 746.667 155.849
1650 1600 1800... (5 Replies)
Hello Team,
I am using the following awk script to calculate the SMA (Single Moving Average) for an specific period but now I would like to include the standard deviation output.
Could you please help me to modify this awk shell script
awk -F, -v points=5 ' { a = $2; ... (4 Replies)
Discussion started by: csierra
4 Replies
LEARN ABOUT DEBIAN
pcap_loop
PCAP_LOOP(3PCAP)PCAP_LOOP(3PCAP)NAME
pcap_loop, pcap_dispatch - process packets from a live capture or savefile
SYNOPSIS
#include <pcap/pcap.h>
typedef void (*pcap_handler)(u_char *user, const struct pcap_pkthdr *h,
const u_char *bytes);
int pcap_loop(pcap_t *p, int cnt,
pcap_handler callback, u_char *user);
int pcap_dispatch(pcap_t *p, int cnt,
pcap_handler callback, u_char *user);
DESCRIPTION
pcap_loop() processes packets from a live capture or ``savefile'' until cnt packets are processed, the end of the ``savefile'' is reached
when reading from a ``savefile'', pcap_breakloop() is called, or an error occurs. It does not return when live read timeouts occur. A
value of -1 or 0 for cnt is equivalent to infinity, so that packets are processed until another ending condition occurs.
pcap_dispatch() processes packets from a live capture or ``savefile'' until cnt packets are processed, the end of the current bufferful of
packets is reached when doing a live capture, the end of the ``savefile'' is reached when reading from a ``savefile'', pcap_breakloop() is
called, or an error occurs. Thus, when doing a live capture, cnt is the maximum number of packets to process before returning, but is not
a minimum number; when reading a live capture, only one bufferful of packets is read at a time, so fewer than cnt packets may be processed.
A value of -1 or 0 for cnt causes all the packets received in one buffer to be processed when reading a live capture, and causes all the
packets in the file to be processed when reading a ``savefile''.
(In older versions of libpcap, the behavior when cnt was 0 was undefined; different platforms and devices behaved differently, so code that
must work with older versions of libpcap should use -1, nor 0, as the value of cnt.)
callback specifies a pcap_handler routine to be called with three arguments: a u_char pointer which is passed in the user argument to
pcap_loop() or pcap_dispatch(), a const struct pcap_pkthdr pointer pointing to the packet time stamp and lengths, and a const u_char
pointer to the first caplen (as given in the struct pcap_pkthdr a pointer to which is passed to the callback routine) bytes of data from
the packet. The struct pcap_pkthdr and the packet data are not to be freed by the callback routine, and are not guaranteed to be valid
after the callback routine returns; if the code needs them to be valid after the callback, it must make a copy of them.
RETURN VALUE
pcap_loop() returns 0 if cnt is exhausted, -1 if an error occurs, or -2 if the loop terminated due to a call to pcap_breakloop() before any
packets were processed. It does not return when live read timeouts occur; instead, it attempts to read more packets.
pcap_dispatch() returns the number of packets processed on success; this can be 0 if no packets were read from a live capture (if, for
example, they were discarded because they didn't pass the packet filter, or if, on platforms that support a read timeout that starts before
any packets arrive, the timeout expires before any packets arrive, or if the file descriptor for the capture device is in non-blocking mode
and no packets were available to be read) or if no more packets are available in a ``savefile.'' It returns -1 if an error occurs or -2 if
the loop terminated due to a call to pcap_breakloop() before any packets were processed. If your application uses pcap_breakloop(), make
sure that you explicitly check for -1 and -2, rather than just checking for a return value < 0.
If -1 is returned, pcap_geterr() or pcap_perror() may be called with p as an argument to fetch or display the error text.
SEE ALSO pcap(3PCAP), pcap_geterr(3PCAP), pcap_breakloop(3PCAP)
24 December 2008 PCAP_LOOP(3PCAP)