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Is there a NumPy function to return the first index of something in an array?
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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...
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...
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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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 ...
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 ...
cscope or ctags why choose one over the other? [closed]
I primarily use vim / gvim as an editor and am looking at using a combination of lxr (the Linux Cross Reference) and either cscope or ctags for exploring the kernel source. However, I haven't ever used either cscope or ctags and would like to hear why one might choose one over the other t...
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...
display: inline-block extra margin [duplicate]
I'm working with a few div s that are set to display: inline-block and have a set height and width . In the HTML, if there is a line break after each div there is an automatic 5px margin add to the right and bottom of the div.
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Formatting floats without trailing zeros
...t formatting rather than scientific notation, etc etc. Yeah, not as slick and elegant as %g, but, it works (and I don't know how to force %g to never use scientific notation;-).
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