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Run a single migration file
...f the ruby file:
rails console
>> require "db/migrate/20090408054532_add_foos.rb"
>> AddFoos.up
Note: newer versions of rails may require AddFoos.new.up rather than AddFoos.up.
An alternative way (without IRB) which relies on the fact that require returns an array of class names:
sc...
How do I check if there are duplicates in a flat list?
...e set() to remove duplicates if all values are hashable:
>>> your_list = ['one', 'two', 'one']
>>> len(your_list) != len(set(your_list))
True
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How does type Dynamic work and how to use it?
...rized:
class DynImpl extends Dynamic {
import reflect.runtime.universe._
def applyDynamic[A : TypeTag](name: String)(args: A*): A = name match {
case "sum" if typeOf[A] =:= typeOf[Int] =>
args.asInstanceOf[Seq[Int]].sum.asInstanceOf[A]
case "concat" if typeOf[A] =:= typeOf[St...
How do I install cygwin components from the command line?
...tended setup mode').
(Note that you need to use setup-x86.exe or setup-x86_64.exe as appropriate.)
See http://cygwin.com/packages/ for the package list.
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How do I install an R package from source?
...hen use install.packages() and set the repos=NULL:
install.packages(path_to_file, repos = NULL, type="source")
Where path_to_file would represent the full path and file name:
On Windows it will look something like this: "C:\\RJSONIO_0.2-3.tar.gz".
On UNIX it will look like this: "/home/blah/R...
Check that an email address is valid on iOS [duplicate]
...ing-an-e-mail-address/
NSString *stricterFilterString = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
NSString *laxString = @"^.+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*$";
NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;
NSPredicate *emailTest = [NS...
Format a datetime into a string with milliseconds
...
Useful with timezone too: date = datetime(2019,5,10) date_with_tz = pytz.timezone('Europe/Rome').localize(date) date_with_tz.isoformat(sep='T', timespec='milliseconds') output: '2019-05-10T00:00:00.000+02:00'
– Ena
May 10 '19 at 9:17
...
Programmatically retrieve memory usage on iPhone
...icture of usage over-all.
#import <mach/mach.h>
// ...
void report_memory(void) {
struct task_basic_info info;
mach_msg_type_number_t size = TASK_BASIC_INFO_COUNT;
kern_return_t kerr = task_info(mach_task_self(),
TASK_BASIC_INFO,
...
Matplotlib make tick labels font size smaller
...lib figure, how can I make the font size for the tick labels using ax1.set_xticklabels() smaller?
10 Answers
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How can I replace every occurrence of a String in a file with PowerShell?
...
(Get-Content file.txt) |
Foreach-Object {$_ -replace '\[MYID\]','MyValue'} |
Out-File file.txt
Note the parentheses around (Get-Content file.txt) is required:
Without the parenthesis the content is read, one line at a time, and flows down the pipeline until i...