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Getting the count of unique values in a column in bash
I have tab delimited files with several columns. I want to count the frequency of occurrence of the different values in a column for all the files in a folder and sort them in decreasing order of count (highest count first). How would I accomplish this in a Linux command line environment?
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explicit casting from super class to subclass
The assignment Dog dog = (Dog) animal; does not generate a compilation error, but at runtime it generates a ClassCastException . Why can't the compiler detect this error?
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Avoid trailing zeroes in printf()
...or the printf() family of functions. What I want is to be able to print a double (or float) with a maximum given number of digits after the decimal point. If I use:
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Replace non-numeric with empty string
Quick add on requirement in our project. A field in our DB to hold a phone number is set to only allow 10 characters. So, if I get passed "(913)-444-5555" or anything else, is there a quick way to run a string through some kind of special replace function that I can pass it a set of characters to ...
Difference between matches() and find() in Java Regex
I am trying to understand the difference between matches() and find() .
5 Answers
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How to disassemble one single function using objdump?
I've got a binary installed on my system, and would like to look at the disassembly of a given function. Preferrably using objdump , but other solutions would be acceptable as well.
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OpenSSL and error in reading openssl.conf file
I am running windows xp 32bit
16 Answers
16
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Do try/catch blocks hurt performance when exceptions are not thrown?
During a code review with a Microsoft employee we came across a large section of code inside a try{} block. She and an IT representative suggested this can have effects on performance of the code. In fact, they suggested most of the code should be outside of try/catch blocks, and that only importa...
Select SQL Server database size
how can i query my sql server to only get the size of database?
10 Answers
10
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Reorder levels of a factor without changing order of values
I have data frame with some numerical variables and some categorical factor variables. The order of levels for those factors is not the way I want them to be.
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