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How to zero pad a sequence of integers in bash so that all have the same width?
...uce the following output:
00010
00011
00012
00013
00014
00015
More generally, bash has printf as a built-in so you can pad output with zeroes as follows:
$ i=99
$ printf "%05d\n" $i
00099
You can use the -v flag to store the output in another variable:
$ i=99
$ printf -v j "%05d" $i
$ echo $j...
HTML5 Canvas vs. SVG vs. div
...rs.
Canvas has the best performance hands-down, but you have to implement all concepts of managed state (object selection, etc) yourself, or use a library.
The long answer:
HTML5 Canvas is simply a drawing surface for a bit-map. You set up to draw (Say with a color and line thickness), draw tha...
IE7 Z-Index Layering Issues
...ex bug, but don't know how to fix it.
I have been playing with z-index all day long.
11 Answers
...
How to make the first option of selected with jQuery
...l($("#target option:first").val()); will work in IE6, because you are literally looking up the first value, and entering it as target's value. Two id lookups instead of one.
– Nicholi
Feb 4 '12 at 1:56
...
Remove duplicated rows using dplyr
... @hadley I like the unique() and distinct() function, however, they all remove the 2nd duplicate from the data frame. what if I want to have all 1st encounters of the duplicate value removed? How could this be done? Thanks for any help!
– FlyingDutch
Feb...
What are the differences between concepts and template constraints?
...To quickly summarise their meanings:
Constraint - A predicate over statically evaluable properties of a type. Purely syntactic requirements. Not a domain abstraction.
Axioms - Semantic requirements of types that are assumed to be true. Not statically checked.
Concepts - General, abstract requireme...
git: difference between “branchname” and “refs/heads/branchname”
...ee heads, remotes, and tags in your .git/refs directory, assuming you have all three types of refs in your repository.
refs/heads/0.58 specifies a branch named 0.58. If you don't specify what namespace the ref is in, git will look in the default ones. This makes using only 0.58 conceivably ambiguous...
How to create the perfect OOP application [closed]
...problem description:
Basic sales tax is applicable at a rate of 10% on all goods, except books, food, and medical products that are exempt. Import duty is an additional sales tax applicable on all imported goods at a rate of 5%, with no exemptions. When I purchase items I receive a receipt which...
Static variable inside of a function in C
...o() to the return from foo(); so it would be re-initialized to 5 on every call.
The keyword static acts to extend the lifetime of a variable to the lifetime of the programme; e.g. initialization occurs once and once only and then the variable retains its value - whatever it has come to be - over al...
C# int to byte[]
...sides, doing the assignment is cheap since it does not copy the memory nor allocate new memory, it just adds a new name to the already allocated array. So why not do it?
– paracycle
May 7 '19 at 15:54
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