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How to measure time in milliseconds using ANSI C?
...nction only measures the amount of time that a process has spent executing and is not accurate on many systems.
You can use this function like this:
struct timeval tval_before, tval_after, tval_result;
gettimeofday(&tval_before, NULL);
// Some code you want to time, for example:
sleep(1);
g...
Best practice to mark deprecated code in Ruby?
...a method as deprecated, so the people using it can easily check their code and catch up. In Java you set @Deprecated and everybody knows what this means.
...
SQLiteDatabase.query method
...By using the Where/Bind -Args version you get automatically escaped values and you don't have to worry if input-data contains '.
Unsafe: String whereClause = "column1='" + value + "'";
Safe: String whereClause = "column1=?";
because if value contains a ' your statement either breaks and you get ex...
How does push notification technology work on Android?
...
From what I've heard during an Android developers conference in Israel:
There is simply a TCP socket waiting in accept mode on a cloud Google server. The TCP connection had been initiated by the Google Play application. That's why Google Play must be inst...
How can I measure the speed of code written in PHP? [closed]
... two solutions :
The quite "naïve" one is using microtime(true) tobefore and after a portion of code, to get how much time has passed during its execution ; other answers said that and gave examples already, so I won"t say much more.
This is a nice solution if you want to benchmark a couple of in...
Can I start the iPhone simulator without “Build and Run”?
I want to delete an app in the simulator before I "build and run". How can I start the simulator so I can do the deletion? If I start it by "build and run" I get a long log output that takes a while because of a bug I'm trying to fix. I'd like to avoid that.
...
Stretch and scale a CSS image in the background - with CSS only
I want that my background image stretch and scale depending on the browser viewport size.
22 Answers
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Search and replace in Vim across all the project files
I'm looking for the best way to do search-and-replace (with confirmation) across all project files in Vim. By "project files" I mean files in the current directory, some of which do not have to be open.
...
Running a cron every 30 seconds
...e offset by 30 seconds:
# Need these to run on 30-sec boundaries, keep commands in sync.
* * * * * /path/to/executable param1 param2
* * * * * ( sleep 30 ; /path/to/executable param1 param2 )
You'll see I've added comments and formatted to ensure it's easy to keep them synchronised.
Bo...
How to append rows to an R data frame
...rs of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n)...