Visit Our UNIX and Linux User Community

Top Forums Shell Programming and Scripting Enter third column & Perform Operation Post 302530258 by Corona688 on Monday 13th of June 2011 11:20:49 AM
Old 06-13-2011
I don't know why you kept -v when you didn't keep all the stuff it's for.

I'm having a hard time telling what you want to do with this code. I tried to show you how to move the expr into awk (where it belongs) but you've just added more of them. (Half of them with incorrect syntax that's probably throwing errors all by itself.) What're all the expr's for? What're you actually trying to do?

---------- Post updated at 09:20 AM ---------- Previous update was at 09:12 AM ----------

Quote:
Originally Posted by Ernst
Can someone tell me what's wrong with this code?

Code:
#!/usr/bin/ksh
echo Enter a value for p
read p
a=16384
b=1228800
c=2914
expr $c '*' $c > e
expr $a/$b > x
cat e | expr $x/$e > y
expr $p '*' $y > d
awk -v '{ print $1, $2, ($2*d); }' addcolumn > add.xls

Taking your code at face value:
Code:
read p
awk -v a=16384 -v b=1228800 -v c=2914 -v p="$p" '
BEGIN {
        e=c*c;
        x=a/b;
        y=x/e;
        d=p*y;
        }
{
        print $1, $2, ($2*d);
}' addcolumn > add.xls

 
Test Your Knowledge in Computers #978
Difficulty: Easy
The Linux kernel development community uses Git to manage the kernel source code.
True or False?

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

How to perform arithmetic operation on date

Hi all, I would appreciate if anyone knows how to perform adding to date. As for normal date, i can easily plus with any number. But when it comes to month end say for example 28 Jun, i need to perform a plus with number 3, it will not return 1 Jul. Thanks in advance for your help. (4 Replies)
Discussion started by: agathaeleanor
4 Replies

2. Shell Programming and Scripting

perform some operation on a specific coulmn starting from a specific line

I have a txt file having rows and coulmns, i want to perform some operation on a specific coulmn starting from a specific line. eg: 50.000000 1 1 1 1000.00000 1000.00000 50000.000 19 19 3.69797533E-07 871.66394 ... (3 Replies)
Discussion started by: shashi792
3 Replies

3. Shell Programming and Scripting

Column operation : cosne and sine operation

I have a txt file with several columns and i want to peform an operation on two columns and output it to a new txt file . file.txt 900.00000 1 1 1 500.00000 500.00000 100000.000 4 4 1.45257346E-07 899.10834 ... (4 Replies)
Discussion started by: shashi792
4 Replies

4. Shell Programming and Scripting

[Solved] Perform an operation to all directories

Sorry, about this thread - I solved my own problem! Thanks for taking a look. edit by bakunin: no problem, but it would have been a nice touch to actually tell us what the solution was. This would have been slightlich more educating than just knowing that you found it. I changed your title to... (0 Replies)
Discussion started by: Blue Solo
0 Replies

5. Shell Programming and Scripting

Help me to perform count & group by operation in shell scripting?

Hi All, I want to display the distinct values in the file and for each distinct value how may occurance or there. Test data: test1.dat 20121105 20121105 20121105 20121105 20121106 20121106 20121106 20121105 I need to display the output like Output (2 Replies)
Discussion started by: bbc17484
2 Replies

6. Homework & Coursework Questions

Using dbms_pipe with C++ to perform daabase operation

I am getting two result: string and int in c++ code. That I want to store into database. The request which generates result is very frequent. So each time performing db operation to store the result is costly for me. So how this can be achived using dbms_sql? I dont have any experience and how... (1 Reply)
Discussion started by: karimkhan
1 Replies

7. Shell Programming and Scripting

How To Perform Mathematical Operation Within If in awk?

Hi All, I am using an awk script as below: awk -F'|' 'BEGIN{OFS="|";} { if ($1==$3 && $3==$7 && $7==$13 && $2==$6 && $6==$11 && $15-$14+1==$11) print $0"|""TRUE"; else print $0"|""FALSE"; }' tempfile.txt In above script, all conditions are being checked except the one which is... (4 Replies)
Discussion started by: angshuman
4 Replies

8. Shell Programming and Scripting

Filter on one column and then perform conditional calculations on another column with a Linux script

Hi, I have a file (stats.txt) with columns like in the example below. Destination IP address, timestamp, TCP packet sequence number and packet length. destIP time seqNo packetLength 1.2.3.4 0.01 123 500 1.2.3.5 0.03 44 1500 1.3.2.5 0.08 44 1500 1.2.3.4 0.44... (12 Replies)
Discussion started by: Zooma
12 Replies

9. Shell Programming and Scripting

awk script to find data in three file and perform replace operation

Have three files. Any other approach with regards to file concatenation or splitting, etc is appreciated If column55(billngtype) of file1 contains YMNC or YPBC then pick the value of column13(documentnumber). Now find this documentnumber in column1(Billdoc) of file2 and grep the corresponding... (4 Replies)
Discussion started by: as7951
4 Replies

10. UNIX for Beginners Questions & Answers

Copy last few lines of a file, perform math operation and iterate further

Hi, I am trying to generate a data of following order: 4 0 1 642 643 4 642 643 1283 1284 4 1283 1284 1924 1925 4 1924 1925 2565 2566 4 2565 2566 3206 3207 4 3206 3207 3847 3848 4 3847 3848 4488 4489 4 4488 4489 5129 5130 ---------------------- 4 1 2 643 644 4 643 644 1284... (6 Replies)
Discussion started by: SaPa
6 Replies
expr(1B)					     SunOS/BSD Compatibility Package Commands						  expr(1B)

NAME
expr - evaluate arguments as a logical, arithmetic, or string expression SYNOPSIS
/usr/ucb/expr argument... DESCRIPTION
The expr utility evaluates expressions as specified by its arguments. After evaluation, the result is written on the standard output. Each token of the expression is a separate argument, so terms of the expression must be separated by blanks. Characters special to the shell must be escaped. Note: 0 is returned to indicate a zero value, rather than the null string. Strings containing blanks or other special characters should be quoted. Integer-valued arguments may be preceded by a unary minus sign. Internally, integers are treated as 32-bit, two's-complement numbers. The operators and keywords are listed below. Characters that need to be escaped are preceded by `'. The list is in order of increasing precedence, with equal precedence operators grouped within {} symbols. expr | expr Returns the evaluation of the first expr if it is neither NULL nor 0; otherwise, returns the evaluation of the second expr if it is not NULL; otherwise, 0. expr & expr Returns the first expr if neither expr is NULL or 0, otherwise returns 0. expr { =, , , <, <=, != } expr Returns the result of an integer comparison if both arguments are integers, otherwise returns the result of a lexical comparison. expr { +, - } expr Addition or subtraction of integer-valued arguments. expr { , /, % } expr Multiplication, division, or remainder of the integer-valued arguments. string : regular-expression match string regular-expression The two forms of the matching operator above are synonymous. The matching operators : and match compare the first argument with the second argument which must be a regular expression. Regular expression syntax is the same as that of regexp(5), except that all pat- terns are "anchored" (treated as if they begin with ^) and therefore ^ is not a special character, in that context. Normally, the matching operator returns the number of characters matched (0 on failure). Alternatively, the ... pattern symbols can be used to return a portion of the first argument. substr string integer-1 integer-2 Extracts the substring of string starting at position integer-1 and of length integer-2 characters. If integer-1 has a value greater than the length of string, expr returns a null string. If you try to extract more characters than there are in string, expr returns all the remaining characters from string. Beware of using negative values for either integer-1 or integer-2 as expr tends to run forever in these cases. index string character-list Reports the first position in string at which any one of the characters in character-list matches a character in string. length string Returns the length (that is, the number of characters) of string. ( expr ) Parentheses may be used for grouping. EXAMPLES
Example 1: Adding an integer to a shell variable Add 1 to the shell variable a. a='expr $a + 1' Example 2: Returning a path name segment Return the last segment of a path name (that is, the filename part). Watch out for / alone as an argument: expr will take it as the divi- sion operator (see BUGS below). # 'For $a equal to either "/usr/abc/file" or just "file"' expr $a : '.*/ $a Example 3: Using // characters to simplify the expression The addition of the // characters eliminates any ambiguity about the division operator and simplifies the whole expression. # A better representation of example 2. expr //$a : '.*/ Example 4: Returning the value of a variable Returns the number of characters in $VAR. expr $VAR : '.*' EXIT STATUS
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. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWscpu | +-----------------------------+-----------------------------+ SEE ALSO
sh(1), test(1), attributes(5), regexp(5) DIAGNOSTICS
syntax error for operator/operand errors non-numeric argument if arithmetic is attempted on such a string division by zero if an attempt to divide by zero is made BUGS
After argument processing by the shell, expr cannot tell the difference between an operator and an operand except by the value. If $a is an =, the command: expr $a = '=' looks like: expr = = = as the arguments are passed to expr (and they will all be taken as the = operator). The following works: expr X$a = X= Note: the match, substr, length, and index operators cannot themselves be used as ordinary strings. That is, the expression: example% expr index expurgatorious length syntax error example% generates the `syntax error' message as shown instead of the value 1 as you might expect. SunOS 5.10 6 Jun 2000 expr(1B)

Featured Tech Videos

All times are GMT -4. The time now is 08:34 PM.
Unix & Linux Forums Content Copyright 1993-2021. All Rights Reserved.
Privacy Policy