Using as much of the orginal code as possible we can create a simple "while true loop around the decision whether to quit or do another calculation. We enter the value for $n1 once at the top of the script and from that point on seed $n1 with the value of a running total in $total.
Code:
echo "please enter a number"
read n1
total=0
while true
do
echo "please choose an operation (or press c/r to exit)"
echo "1. add"
echo "2. subtract"
echo "3. divide"
echo "4. multiply"
read opr
# Exit if user pressed carriage-return
if [ "${opr}""X" = "X" ]
then
break
fi
echo "please enter a number again"
read n2
# Do the calculation required
if [ $opr = "1" ]
then
total=$((n1+n2))
elif [ $opr = "2" ]
then
total=$((n1-n2))
elif [ $opr = "3" ]
then
total=$((n1/n2))
elif [ $opr = "4" ]
then
total=$((n1*n2))
fi
# Display running total
echo ""
echo " Running total: $total"
echo ""
# Seed $n1 with the current value of $total
n1=$total
done
The modified script keeps on asking for more calculation on the running total until the user presses carriage-return.
You could add a line just before "break" to display "Final total is $total" if that is a requirement.
Try it and enjoy.
Last edited by methyl; 12-19-2011 at 08:38 PM..
Reason: inconsistent f1 n1
Heres a script i wrote as a bit of practise. What it does is insert a line in the middle of a file. The line being $1 and the file being $2
#!/bin/bash
rm tempfile
touch tempfile
count=1
linenum= `wc -l < $2`
if
then
echo $1 >> $2
else
even=`expr "$linenum" % 2`
if
then... (3 Replies)
Hallo everyone
I might just be being dumb, but I am using the BASH shell and cannot get the following script to work:
x=0
while
do
echo $x
x=´echo "$x + 1" | bc´
done
Can anybody help me out. I am just get a repeating output saying:
bc: command not found
0 + 1: command not... (5 Replies)
i have the following process running in background:
when i give "ps -lef"
------------------------------------------------------------------------
user2
user1
user1
user3
user1
user4
user5
user4
user3
user4
user2
user1
user1
user3
user1
user4 (3 Replies)
Hi expert,
I'm using csh
Code:
#!/bin/csh
set x = 0
set number = `awk '{array=$0} END {print array;}'`
i want to use for loop to store data to $number repeatly
untill x = 23
How to use c shell for loop? (2 Replies)
I need to chmod a bunch of files with a specific extension in one directory.
If I understand correctly first I would run ls command like this
ls -R | grep .mp3 > /tmp/list
once I have the output file I should be able to run a loop to chmod all the files in the list created.
This is where... (5 Replies)
Hello,
I'm trying to write a while loop for a decimal value in tcsh which I know can't be done. Instead I want my increments to be one order of magnitude too large and then divide it by 10 when I use the variable. However, I don't know how to divide my variable and set it as another.
set... (1 Reply)
Does any body can help me with a loop in this example?
if
then
if
then
runner=$(grep "$1" "$2")
runne=$(grep "$1" "$3")
run=$(grep "$1" "$4")
fi
fi
#
# Message on screen... (3 Replies)
I am trying to make a calculator. The user Enters number 1, chooses and operation, enters number 2, then chooses another operation or for the answer to be displayed.
eg. 1 + 1 = or 1 + 1 + 2 + 1 =
Both of these should be possible.
#!/bin/bash
read -p "what's the first number? " n1... (3 Replies)
Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known/data:
Script a simple calculator. In the command line enter the script file
/home/etc/mycalc or /home/etc/mycalc 1 +... (6 Replies)
ADE is a UNIX environment for the ancient AMIGA A1200. By default this does NOT have the 'bc' command line calculator.
Although I did a DEMO code to create a C source and compile it under python 1.4.0 and ADE using ksh88 and the gcc of the day, I decided to create this baby that requires no Python... (2 Replies)
Discussion started by: wisecracker
2 Replies
LEARN ABOUT CENTOS
total
TOTAL(1) General Commands Manual TOTAL(1)NAME
total - sum up columns
SYNOPSIS
total [ -m ][ -sE | -p | -u | -l ][ -i{f|d}[N] ][ -o{f|d} ][ -tC ][ -N [ -r ]] [ file .. ]
DESCRIPTION
Total sums up columns of real numbers from one or more files and prints out the result on its standard output.
By default, total computes the straigt sum of each input column, but multiplication can be specified instead with the -p option. Likewise,
the -u option means find the upper limit (maximum), and -l means find the lower limit (minimum).
Sums of powers can be computed by giving an exponent with the -s option. (Note that there is no space between the -s and the exponent.)
This exponent can be any real number, positive or negative. The absolute value of the input is always taken before the power is computed
in order to avoid complex results. Thus, -s1 will produce a sum of absolute values. The default power (zero) is interpreted as a straight
sum without taking absolute values.
The -m option can be used to compute the mean rather than the total. For sums, the arithmetic mean is computed. For products, the geomet-
ric mean is computed. (A logarithmic sum of absolute values is used to avoid overflow, and zero values are silently ignored.)
If the input data is binary, the -id or -if option may be given for 64-bit double or 32-bit float values, respectively. Either option may
be followed immediately by an optional count, which defaults to 1, indicating the number of double or float binary values to read per
record on the input file. (There can be no space between the option and this count.) Similarly, the -od and -of options specify binary
double or float output, respectively. These options do not need a count, as this will be determined by the number of input channels.
A count can be given as the number of lines to read before computing a result. Normally, total reads each file to its end before producing
its result, but this behavior may be overridden by inserting blank lines in the input. For each blank input line, total produces a result
as if the end-of-file had been reached. If two blank lines immediately follow each other, total closes the file and proceeds to the next
one (after reporting the result). The -N option (where N is a decimal integer) tells total to produce a result and reset the calculation
after every N input lines. In addition, the -r option can be specified to override reinitialization and thus give a running total every N
lines (or every blank line). If the end of file is reached, the current total is printed and the calculation is reset before the next file
(with or without the -r option).
The -tC option can be used to specify the input and output tab character. The default tab character is TAB.
If no files are given, the standard input is read.
EXAMPLE
To compute the RMS value of colon-separated columns in a file:
total -t: -m -s2 input
To produce a running product of values from a file:
total -p -1 -r input
BUGS
If the input files have varying numbers of columns, mean values will certainly be off. Total will ignore missing column entries if the tab
separator is a non-white character, but cannot tell where a missing column should have been if the tab character is white.
AUTHOR
Greg Ward
SEE ALSO cnt(1), neaten(1), rcalc(1), rlam(1), tabfunc(1)RADIANCE 2/3/95 TOTAL(1)