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Remove unwanted parts from strings in a column
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If you need the result converted to an integer, you can use Series.astype,
df['result'] = df['result'].str.replace(r'\D', '').astype(int)
df.dtypes
time object
result int64
dtype: object
If you don't want to modify df in-place, use Dat...
android pick images from gallery
...ll example for request permission (if need), pick image from gallery, then convert image to bitmap or file
AndroidManifesh.xml
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
Activity
class MainActivity : AppCompatActivity() {
override fun onCreate(savedIns...
How do I make my string comparison case insensitive?
...e best would be using s1.equalsIgnoreCase(s2): (see javadoc)
You can also convert them both to upper/lower case and use s1.equals(s2)
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When to use std::size_t?
...ff_t is long on 32 and 64 bit systems.
This means that you always have to convert to and from size_t whenever you interact with a std::containers, which not very beautiful. But on a going native conference the authors of c++ mentioned that designing std::vector with an unsigned size_t was a mistake...
Swift double to string
...g = double.description
update Xcode 7.1 • Swift 2.1:
Now Double is also convertible to String so you can simply use it as you wish:
let double = 1.5
let doubleString = String(double) // "1.5"
Swift 3 or later we can extend LosslessStringConvertible and make it generic
Xcode 11.3 • Swift 5.1 ...
CharSequence VS String in Java?
...ne such class, a concrete implementation of CharSequence.
You said:
converting from one to another
There is no converting from String.
Every String object is a CharSequence.
Every CharSequence can produce a String. Call CharSequence::toString. If the CharSequence happens to be a String, ...
Is it safe to use -1 to set all bits to true?
...
why is -1 guaranteed to be converted to all ones? Is that guaranteed by the standard?
– jalf
Apr 30 '09 at 22:11
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What happens when a computer program runs?
...lso note, these aren't actual lines of C code executing. The compiler has converted them into machine language instructions in your executable. They are then (generally) copied from the TEXT area into the CPU pipeline, then into the CPU registers, and executed from there. [This was incorrect. Se...
Is the practice of returning a C++ reference variable evil?
...const&", what actually happens is that the return statement implicitly converts the temp, which is of type T, to type "T const&" as per 6.6.3.2 (a legal conversion but one which does not extend lifetime), and then the calling code initialises the ref of type "T const&" with the function'...
Fast way to get image dimensions (not filesize)
...ng 20-60 KB read by "identify" for 5-335 MB images (I also tested against "convert" which showed all bytes being read). So it looks like "identify" is a good choice here (since it supports all popular formats and reads just the header).
– coderforlife
Feb 12 '1...