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Determining complexity for recursive functions (Big O notation)
...complexity of these recursive functions. I know how to solve simple cases, but I am still trying to learn how to solve these harder cases. These were just a few of the example problems that I could not figure out. Any help would be much appreciated and would greatly help in my studies, Thank you! ...
Cleaning `Inf` values from an R dataframe
...apply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)
invisible(lapply(names(DT),function(.name) set(DT, which(is.infinite(DT[[.name]])), j = .name,value =NA)))
Or using column ...
How can I use an array of function pointers?
...Array of Function pointers), with the syntax detailed.
int sum(int a, int b);
int subtract(int a, int b);
int mul(int a, int b);
int div(int a, int b);
int (*p[4]) (int x, int y);
int main(void)
{
int result;
int i, j, op;
p[0] = sum; /* address of sum() */
p[1] = subtract; /* address of...
How to read the output from git diff?
...for git-diff is rather long, and explains many cases which don't seem to be necessary for a beginner. For example:
6 Answ...
Python != operation vs “is not”
...t. It checks whether the right hand side and the left hand side are equal objects (according to their __eq__ or __cmp__ methods.)
is is an identity test. It checks whether the right hand side and the left hand side are the very same object. No methodcalls are done, objects can't influence the is op...
Resolve Type from Class Name in a Different Assembly
...e I need to resolve the Type of a class. This class exists in another assembly with the namespace similar to:
6 Answers
...
How to do 3 table JOIN in UPDATE query?
...
the answer is yes you can
try it like that
UPDATE TABLE_A a
JOIN TABLE_B b ON a.join_col = b.join_col AND a.column_a = b.column_b
JOIN TABLE_C c ON [condition]
SET a.column_c = a.column_c + 1
EDIT:
For general Update join :
UPDATE TABLEA a
JOIN TABLEB b ON...
Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
I've long been under the impression that goto should never be used if possible. While perusing libavcodec (which is written in C) the other day, I noticed multiple uses of it. Is it ever advantageous to use goto in a language that supports loops and functions? If so, why?
...
Extending from two classes
...nt Interfaces from many sources.
Extending multiple classes is not available. The only solution I can think of is not inheriting either class but instead having an internal variable of each class and doing more of a proxy by redirecting the requests to your object to the object that you want them ...
What is the 'new' keyword in JavaScript?
The new keyword in JavaScript can be quite confusing when it is first encountered, as people tend to think that JavaScript is not an object-oriented programming language.
...