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Undefined reference to `sin` [duplicate]
...As a result, you can compile your .o object files, but not build your executable.
As Paul has already mentioned add "-lm" to link with the math library in the step where you are attempting to generate your executable.
In the comment, linuxD asks:
Why for sin() in <math.h>, do we need -lm...
How does JPA orphanRemoval=true differ from the ON DELETE CASCADE DML clause
... i call department.remove(emp); that employee will be deleted from the emp table without even calling commit()
– JavaTechnical
Jun 10 '14 at 12:00
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...
JavaScript + Unicode regexes
...ate, and Escape check boxes, which strike a balance between avoiding unprintable characters and minimizing the size of the regex.
Here are some common expansions of different Unicode properties:
\p{L} (Letters):
[A-Za-z\u00AA\u00B5\u00BA\u00C0-\u00D6\u00D8-\u00F6\u00F8-\u02C1\u02C6-\u02D1\u02E0-\...
How to list all methods for an object in Ruby?
..._of", "execute_simple_calculation", "attr_protected",
"reflections", "table_name_prefix", ...
Note that methods is a method for Classes and for Class instances.
Here's the methods that my User class has that are not in the ActiveRecord base class:
>> User.methods - ActiveRecord::Base...
SQL : BETWEEN vs =
...r a range. This is especially true if you have similar field names in your table.
If, say, our table has both a transactiondate and a transitiondate, if I read
transactiondate between ...
I know immediately that both ends of the test are against this one field.
If I read
transactiondate>='2...
Find XOR of all numbers in a given range
...f() function calculates the XOR total run from [0, a]. Take a look at this table for 4-bit numbers:
0000 <- 0 [a]
0001 <- 1 [1]
0010 <- 3 [a+1]
0011 <- 0 [0]
0100 <- 4 [a]
0101 <- 1 [1]
0110 <- 7 [a+1]
0111 <- 0 [0]
1000 <- 8 [a]
1001 <- 1 [1]
1010 <- 11 [...
Difference between float and decimal data type
...
This is what I found when I had this doubt.
mysql> create table numbers (a decimal(10,2), b float);
mysql> insert into numbers values (100, 100);
mysql> select @a := (a/3), @b := (b/3), @a * 3, @b * 3 from numbers \G
*************************** 1. row *************************...
Difference between CTE and SubQuery?
...
The main advantage of the Common Table Expression (when not using it for recursive queries) is encapsulation, instead of having to declare the sub-query in every place you wish to use it, you are able to define it once, but have multiple references to it.
H...
When should an IllegalArgumentException be thrown?
...m and double price. The price for corresponding item is read from database table. I simply multiply the total number of item purchased with the price value and return the result. Although I am always sure at my end(Application end) that price field value in the table could never be negative .But wha...
Virtual functions and performance - C++
...ual is a per-function attribute. A function only needs to be defined via vtable if it's marked as virtual or if it's overriding a base class that has it as virtual. You'll often see classes that have a group of virtual functions for public interface, and then a lot of inline accessors and so on. (...