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How do you know what to test when writing unit tests? [closed]
... code, or a completely new feature.
Start simple. Don’t go running off and trying to get your head round
a testing framework as well as being
TDD-esque. Debug.Assert works fine.
Use it as a starting point. It doesn’t
mess with your project or create
dependencies.
Start positive. Yo...
Compare two DataFrames and output their differences side-by-side
...ny(df1.dtypes != df2.dtypes):
"Data Types are different, trying to convert"
df2 = df2.astype(df1.dtypes)
if df1.equals(df2):
return None
else:
# need to account for np.nan != np.nan returning True
diff_mask = (df1 != df2) & ~(df1.isnull() & df2...
What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
Why were 181783497276652981 and 8682522807148012 chosen in Random.java ?
3 Answers
...
What are the rules for evaluation order in Java?
I am reading some Java text and got the following code:
5 Answers
5
...
What is the most efficient way to deep clone an object in JavaScript?
...tring representation of the date in ISO format, which JSON.parse() doesn't convert back to a Date object. See this answer for more details.
Additionally, please note that, in Chrome 65 at least, native cloning is not the way to go. According to JSPerf, performing native cloning by creating a new fu...
How to set time zone of a java.util.Date?
...ies for generating all kinds of other String formats.
If required, you can convert from Joda-Time DateTime to a java.util.Date.
Java.util.Date date = dateTimeIndia.toDate();
Search StackOverflow for "joda date" to find many more examples, some quite detailed.
†Actually there is a time zone embed...
What guarantees are there on the run-time complexity (Big-O) of LINQ methods?
I've recently started using LINQ quite a bit, and I haven't really seen any mention of run-time complexity for any of the LINQ methods. Obviously, there are many factors at play here, so let's restrict the discussion to the plain IEnumerable LINQ-to-Objects provider. Further, let's assume that any...
The purpose of Model View Projection Matrix
...
Because matrices are convenient. Matrices help to convert locations/directions with respect to different spaces (A space can be defined by 3 perpendicular axes and an origin).
Here is an example from a book specified by @legends2k in comments.
The residents of Cartesia ...
Why is rbindlist “better” than rbind?
...t shines are
Fast vectorized merge of list of data.frames by row
Trouble converting long list of data.frames (~1 million) to single data.frame using do.call and ldply
These have benchmarks that show how fast it can be.
rbind.data.frame is slow, for a reason
rbind.data.frame does lots of check...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
...
Standard C Preprocessor
$ cat xx.c
#define VARIABLE 3
#define PASTER(x,y) x ## _ ## y
#define EVALUATOR(x,y) PASTER(x,y)
#define NAME(fun) EVALUATOR(fun, VARIABLE)
extern void NAME(mine)(char *x);
$ gcc -E xx.c
# 1 "xx.c"
# ...