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Why aren't programs written in Assembly more often? [closed]
It seems to be a mainstream opinion that assembly programming takes longer and is more difficult to program in than a higher level language such as C. Therefore it seems to be recommend or assumed that it is better to write in a higher level language for these reasons and for the reason of better po...
How to find list of possible words from a letter matrix [Boggle Solver]
...ictionary word that could be a solution must use only the grid's
# letters and have length >= 3. (With a case-insensitive match.)
import re
alphabet = ''.join(set(''.join(grid)))
bogglable = re.compile('[' + alphabet + ']{3,}$', re.I).match
words = set(word.rstrip('\n') for word in open('words')...
Regex - how to match everything except a particular pattern
...particular pattern? I'm faced with a situation where I have to match an (A and ~B) pattern.
8 Answers
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Empty arrays seem to equal true and false at the same time
...t (Array is instance of Object in JS) will check if the object is present, and returns true/false.
When you call if (arr == false) you compare values of this object and the primitive false value. Internally, arr.toString() is called, which returns an empty string "".
This is because toString cal...
Is there a NumPy function to return the first index of something in an array?
...
Yes, here is the answer given a NumPy array, array, and a value, item, to search for:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your it...
Valid values for android:fontFamily and what they map to?
In the answer to this question the user lists values for android:fontFamily and 12 variants (see below). Where do these values come from? The documentation for android:fontFamily does not list this information in any place (I checked here , and here ). The strings are listed in the Android ...
Counting null and non-null values in a single query
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This works for Oracle and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) fro...
How do I use prepared statements in SQlite in Android?
How do I use prepared statements in SQlite in Android?
5 Answers
5
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xcodebuild says does not contain scheme
...two versions of things -- the "I'm busy, so just the facts please" version and a more involved discussion and rationale. Both of these versions assume you are trying to build from a Workspace file; if you aren't then my apologies as this mostly applicable to workspace-based projects.
Condensed 'Fi...
What's a concise way to check that environment variables are set in a Unix shell script?
...(an empty string) is OK — not exactly what you want, but the alternative and older notation.
The second variant (using :?) requires DEST to be set and non-empty.
If you supply no message, the shell provides a default message.
The ${var?} construct is portable back to Version 7 UNIX and the Bourne ...