hi i am using bash shell to perform some subraction. here is what i have:
i have a while loop and am using i as a counter.
for example array1[1] has -0.7145 and array2[1] has -0.7041.
when i try the above command, i get expr: non-numeric argument. any ideas how i can do this subtraction?
thanks
:confused:
Is it possible to delete array elements dynamically.For instance,consider an array( a b c d ) ,now can i delete array (the third element 'c').So that the array becomes array(a b d)..
Thanks in advance!! (1 Reply)
Hi,
I am writing a bash shell script. I would like to execute a statement only if an array contains a specific value. For example:
array=(1 3 5 7)
I would like to execute the statement only if the value 3 is present in ${array}.
Thanks for any help,
Mike (1 Reply)
hi guys,
i have the following script and when i run it i get blank lines on the screen.. i am trying to display the contents of array var..
#!/usr/bin/bash
var=`awk 'NR>20&&NR<31' try.sum | awk '{print $4}'`
echo "${var}" (1 Reply)
hi guys,
i have an array called ARRAY which has elements in it... i am trying to assign elements of ARRAY to master_array..
i get a =: command not found error..
i=0
while
do
${master_array}=${ARRAY}
((i++))
done
is there something i am missing? (4 Replies)
Hi all,
I have a file that contains many lines, but only a few are of my interest, so I'm cutting it with grep + awk, and the result I get is for example
line 0
line 1
line 2
line 3
line n
Now I want to store each line in an array "cell" so I can use it later calling to
${array},... (2 Replies)
trying to sum elements in an array using bc and getopt,i have a file with names and thier vaules if the names appears 3 times i should multiply its value with 3 then find the sum of all the elements together
cat foo.txt
max 2.3
henry 3
fransis 4.5
max 2.3
henry 3
max 2.3
it should... (1 Reply)
I have the following code and for some reason when I call the program using
/home/tcdata/tatsh/trunk/hstmy/bin/bash/raytrac.bash --cmod=jcdint.cmod
I get
hasArgument =
hasArgument = true
Somehow the array element is returning even though I have not chosen the option.
... (41 Replies)
Hello all .
I have two arrays.
${ARRAY_MOUNT_POINT_CAPACITY}
${ARRAY_MOUNT_POINT_CAPACITY}.
Whats the synatx of subtracting their values , placing them in variable V1 and then echoeing it ???
Ive tried expr and let ...gives me ./test_code.sh: difference: bad number (3 Replies)
Hi all,
i'm making some test on a data file. Imagine i have two columns inside it :
80377,20
80377,20
80379,19
80378,20
80380,20
80382,20
80381,21
Just to understand how can it works, imagine to subtract 100 to the number in the first column when the other one in the second... (4 Replies)
I am sharing a code snippet.
for (( i=0; i<=$(( $count -1 )); i++ ))
do
first=${barr2}
search=${barr1}
echo $first
echo "loop begins"
for (( j=0; j<=5000; j++ ))
do
if } == $search ]]; then
echo $j
break;
fi
done
second=${harr2}
echo $second (2 Replies)
Discussion started by: ngabrani
2 Replies
LEARN ABOUT V7
expr
EXPR(1) General Commands Manual EXPR(1)NAME
expr - evaluate arguments as an expression
SYNOPSIS
expr arg ...
DESCRIPTION
The arguments are taken as an expression. After evaluation, the result is written on the standard output. Each token of the expression is
a separate argument.
The operators and keywords are listed below. The list is in order of increasing precedence, with equal precedence operators grouped.
expr | expr
yields the first expr if it is neither null nor `0', otherwise yields the second expr.
expr & expr
yields the first expr if neither expr is null or `0', otherwise yields `0'.
expr relop expr
where relop is one of < <= = != >= >, yields `1' if the indicated comparison is true, `0' if false. The comparison is numeric if
both expr are integers, otherwise lexicographic.
expr + expr
expr - expr
addition or subtraction of the arguments.
expr * expr
expr / expr
expr % expr
multiplication, division, or remainder of the arguments.
expr : expr
The matching operator compares the string first argument with the regular expression second argument; regular expression syntax is
the same as that of ed(1). The (...) pattern symbols can be used to select a portion of the first argument. Otherwise, the
matching operator yields the number of characters matched (`0' on failure).
( expr )
parentheses for grouping.
Examples:
To add 1 to the Shell variable a:
a=`expr $a + 1`
To find the filename part (least significant part) of the pathname stored in variable a, which may or may not contain `/':
expr $a : '.*/(.*)' '|' $a
Note the quoted Shell metacharacters.
SEE ALSO ed(1), sh(1), test(1)DIAGNOSTICS
Expr returns the following exit codes:
0 if the expression is neither null nor `0',
1 if the expression is null or `0',
2 for invalid expressions.
EXPR(1)