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What is in your Mathematica tool bag? [closed]
...and Sow which mimics/extends the behavior of GatherBy:
SelectEquivalents[x_List,f_:Identity, g_:Identity, h_:(#2&)]:=
Reap[Sow[g[#],{f[#]}]&/@x, _, h][[2]];
This allows me to group lists by any criteria and transform them in the process. The way it works is that a criteria function (f...
How do I analyze a program's core dump file with GDB when it has command-line parameters?
... crash scenario
Program terminated with signal 11, Segmentation fault.
#0 __strlen_ia32 () at ../sysdeps/i386/i686/multiarch/../../i586/strlen.S:99
99 ../sysdeps/i386/i686/multiarch/../../i586/strlen.S: No such file or directory.
in ../sysdeps/i386/i686/multiarch/../../i586/strlen.S
(gdb)
...
Add a new item to a dictionary in Python [duplicate]
...
default_data['item3'] = 3
Easy as py.
Another possible solution:
default_data.update({'item3': 3})
which is nice if you want to insert multiple items at once.
...
Multiple Inheritance in PHP
...
This is both a question and a solution....
What about the magical _call(),_get(), __set() methods? I have not yet tested this solution but what if you make a multiInherit class. A protected variable in a child class could contain an array of classes to inherit. The constructor in the multi-...
Finding all possible combinations of numbers to reach a given sum
...t those that reach the target. Here is the algorithm in Python:
def subset_sum(numbers, target, partial=[]):
s = sum(partial)
# check if the partial sum is equals to target
if s == target:
print "sum(%s)=%s" % (partial, target)
if s >= target:
return # if we re...
Max length UITextField
...
With Swift 5 and iOS 12, try the following implementation of textField(_:shouldChangeCharactersIn:replacementString:) method that is part of the UITextFieldDelegate protocol:
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) ->...
Django set default form values
...
@Phlip: Don't override View.get_form to set initial data. Any CBV with a FormMixin (basically all CBVs that create or edit data) can either use a class-level initial variable (for unchanging defaults) or you can override FormMixin.get_initial() to return ...
Remove not alphanumeric characters from string
...:
input.replace(/\W/g, '')
Note that \W is the equivalent of [^0-9a-zA-Z_] - it includes the underscore character. To also remove underscores use e.g.:
input.replace(/[^0-9a-z]/gi, '')
The input is malformed
Since the test string contains various escaped chars, which are not alphanumeric, it ...
How to get all registered routes in Express?
...t app.routes :-)
express 4.x
Applications - built with express()
app._router.stack
Routers - built with express.Router()
router.stack
Note: The stack includes the middleware functions too, it should be filtered to get the "routes" only.
...
Why does 'continue' behave like 'break' in a Foreach-Object?
..., it simulates the continue in a loop.
1..100 | ForEach-Object {
if ($_ % 7 -ne 0 ) { return }
Write-Host "$($_) is a multiple of 7"
}
There is a gotcha to be kept in mind when refactoring. Sometimes one wants to convert a foreach statement block into a pipeline with a ForEach-Object cmdl...