input:
Output:
Basically I am trying to calculate the result of "the path" in $3 where the operators follow the number and not preceding them like we normally do:
rec_10: +1+2-2=1
But I realise (I am sure there is a good reason for that) that awk does handle basic arithmetic operations, like:
(+1) + (2) + (-2) = 1
Giving that to awk:
makes it stuck in a loop.
Therefore, I think the approach of putting the numbers and operators in the right order (code below) would not work at the end anyway:
output:
Is there any awk trick I could use instead?
Maybe using an increment x++, but instead of the '+' sign writing some variables like for example:
The code above is just an example and returns:
Last edited by beca123456; 12-18-2015 at 09:51 PM..
I have no idea what you are trying to do. Arithmetic operators (except unary minus) work on two operands. Therefore, a arithmetic formula has one more operand than there are operators. But, your example has 3 operands and 3 operators.
Are you saying that you want each number to have a trailing + or - sign to indicate whether the number is positive or negative and you then want to add up all of the signed numbers?
Thanks again for your help.
No, it has been a long time I left school (I should have probably taken more programming classes though).
Long story short. I have a string like this:
Which actually defines 3 numbers (written in the usual format below):
I am trying to get the result of the sum of these numbers:
(+1) + (+2) + (-1)
Which is equal to:
1+2-1=2
The + or - signs are actually not operators. They tell you if the number before the sign is positive or negative.
... ... ...
The code above is just an example and returns:
I am having trouble following the logic of your script.
The diagnostic you are getting is because the sequence x(i) is a request to call the function named x with the parameter i, you haven't defined any functions, and the function x is not one that is defined by gawk. Furthermore, you can't have a variable and a function with the same name.
Note that the statement: x==0; is a logical expression (not an assignment statement) returning the value 1 if the variable x is zero or an empty string; otherwise it returns 0. (Note that the value of that logical expression doesn't affect the behavior of this script in any way; it does not assign a value to x.)
Although the gawk statement:
splits the 2nd input field into the array b[] with each element of b[] being set to one character from that field and sets a to the number of characters found; using an empty string as an ERE specifying the field delimiter is not available in all versions of awk (including the one I am using on OS X).
You might want to try something more like:
which, if file contains:
produces the output:
This was tested using awk on OS X, but should also work with gawk on any Linux system.
If someone wants to try this script on a Solaris/SunOS system, change awk to /usr/xpg4/bin/awk or nawk.
This User Gave Thanks to Don Cragun For This Post:
This is a nice approach, and works fine with gawk and other awk implementations that use FS="" to split each input character into a field. A similar approach that doesn't depend on this behavior (which the standards say produces unspecified results) would be:
which also has a little feature creep allowing a decimal point to be included in the input numbers (sparked by RudiC's code using %f instead of %d in the sprintf() format string).
If you change:
in RudiC's script to:
his script will also handle floating point values in awk versions where:
doesn't produce a syntax error.
This User Gave Thanks to Don Cragun For This Post:
The problem reminds me of a rudimentary RPN calculator that I recently did. As it expects operands and operators in separate fields, I added a gsub with spaces at the begin of each step:
( and, in principle, it would need a 0 operand in the beginning. It uses the "|" now resulting in a zero value to start with)
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0800234567|JAN|2017|JAN|2018|0800234567|4|2.5812|10.32|
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git branch -r | while read brname ; do
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-------
-------
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