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how to check if object already exists in a list
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It depends on the needs of the specific situation. For example, the dictionary approach would be quite good assuming:
The list is relatively stable (not a lot of inserts/deletions, which dictionaries are not optimized for)
T...
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 item at two loc...
How do I profile memory usage in Python?
I've recently become interested in algorithms and have begun exploring them by writing a naive implementation and then optimizing it in various ways.
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Why is 1/1/1970 the “epoch time”?
...ns of unix measured system time in 1/60 s intervals. This meant that a 32-bit unsigned integer could only represent a span of time less than 829 days. For this reason, the time represented by the number 0 (called the epoch) had to be set in the very recent past. As this was in the early 1970s, the e...
What is a Maven artifact?
What is an artifact and why does Maven need it?
9 Answers
9
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How to get the directory of the currently running file?
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This should do it:
import (
"fmt"
"log"
"os"
"path/filepath"
)
func main() {
dir, err := filepath.Abs(filepath.Dir(os.Args[0]))
if err != nil {
log.Fatal(err)
}
fmt.Println(dir)
}
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Is there an eval() function in Java? [duplicate]
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You can use the ScriptEngine class and evaluate it as a Javascript string.
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("js");
Object result = engine.eval("4*5");
There may be a better way, but this one works.
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keep rsync from removing unfinished source files
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It seems to me the problem is transferring a file before it's complete, not that you're deleting it.
If this is Linux, it's possible for a file to be open by process A and process B can unlink the file. There's no error, bu...
Why does Python pep-8 strongly recommend spaces over tabs for indentation?
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The answer was given right there in the PEP [ed: this passage has been edited out in 2013]. I quote:
The most popular way of indenting Python is with spaces only.
What other underlying reason do you need?
To put it less bluntly: Consider also the scope of the PEP as stated in the very first...
How to round up the result of integer division?
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For languages with a proper Euclidian-division operator such as Python, an even simpler approach would be pageCount = -((-records) // recordsPerPage).
– supercat
Jul 4 '18 at 16:45
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