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What is the difference between JSON and Object Literal Notation?
...iterals or number literals. You are correct that at runtime, those are all converted to strings (but we have symbols now as well).
– Felix Kling
Mar 24 '16 at 18:17
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Combine two columns of text in pandas dataframe
...arter"]
If one (or both) of the columns are not string typed, you should convert it (them) first,
df["period"] = df["Year"].astype(str) + df["quarter"]
Beware of NaNs when doing this!
If you need to join multiple string columns, you can use agg:
df['period'] = df[['Year', 'quarter', ...]].a...
How to get Scala List from Java List?
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EDIT: Note that this is deprecated since 2.12.0. Use JavaConverters instead. (comment by @Yaroslav)
Since Scala 2.8 this conversion is now built into the language using:
import scala.collection.JavaConversions._
...
lst.toList.foreach{ node => .... }
works. asScala did not ...
About “*.d.ts” in TypeScript
...of file is something like "head file" in C++ but for JS only. But I cannot convert a pure JS file to *.d.ts file unless I forcely change the *.js to *.ts . So I have three files:
a JS file, a TS file and a *.d.ts file.
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How to filter specific apps for ACTION_SEND intent (and set a different text for each app)
...(intent, packageName, ri.loadLabel(pm), ri.icon));
}
}
// convert intentList to array
LabeledIntent[] extraIntents = intentList.toArray( new LabeledIntent[ intentList.size() ]);
openInChooser.putExtra(Intent.EXTRA_INITIAL_INTENTS, extraIntents);
startActivity(openInChoo...
How to Calculate Execution Time of a Code Snippet in C++
...HighDateTime;
uint64 ret = li.QuadPart;
ret -= 116444736000000000LL; /* Convert from file time to UNIX epoch time. */
ret /= 10000; /* From 100 nano seconds (10^-7) to 1 millisecond (10^-3) intervals */
return ret;
#else
/* Linux */
struct timeval tv;
gettimeofday(&tv, NULL);
uint64 ...
Why doesn't c++ have &&= or ||= for booleans?
...different value such as 2. When assigning that value to a bool, it will be converted to true as per the standard.
The only way to get an invalid value into a bool is by using reinterpret_cast on pointers:
int i = 2;
bool b = *reinterpret_cast<bool*>(&i);
b |= true; // MAY yield 3 (but do...
Storing Objects in HTML5 localStorage
...vaScript object in HTML5 localStorage , but my object is apparently being converted to a string.
22 Answers
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data.frame rows to a list
I have a data.frame which I would like to convert to a list by rows, meaning each row would correspond to its own list elements. In other words, I would like a list that is as long as the data.frame has rows.
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Where did the name `atoi` come from?
In the C language where did they come up with the name atoi for converting a string to an integer? The only thing I can think of is Array To Integer for an acronym but that doesn't really make sense.
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