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Why do I get TypeError: can't multiply sequence by non-int of type 'float'?
...hat everyone here talked about multiplying a float with a string (but here all my element were floats all along) so the problem was actually using the * operator on a list.
For example:
import math
import numpy as np
alpha = 0.2
beta=1-alpha
C = (-math.log(1-beta))/alpha
coff = [0.0,0.01,0.0,0.3...
How to use a wildcard in the classpath to add multiple jars? [duplicate]
...ldcard character *, which is considered equivalent to specifying a list of all the files in the directory with the extension .jar or .JAR. For example, the class path entry foo/* specifies all JAR files in the directory named foo. A classpath entry consisting simply of * expands to a list of all the...
What is “rvalue reference for *this”?
Came across a proposal called "rvalue reference for *this" in clang's C++11 status page .
3 Answers
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Postgresql - unable to drop database because of some auto connections to DB
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(and possibly other users/roles; see \l+ in psql)
You can then terminate all connections to this db except your own:
SELECT pid, pg_terminate_backend(pid)
FROM pg_stat_activity
WHERE datname = current_database() AND pid <> pg_backend_pid();
On older versions pid was called procpid so you'...
Difference between the Facade, Proxy, Adapter and Decorator design patterns? [closed]
...o a new interface. In the case of the former, multiple inheritance is typically employed. In the latter case, the object is wrapped by a conforming adapter object and passed around. The problem we are solving here is that of non-compatible interfaces.
Facade is more like a simple gateway to a compl...
How to remove all characters after a specific character in python?
I have a string. How do I remove all text after a certain character? ( In this case ... )
The text after will ... change so I that's why I want to remove all characters after a certain one.
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in javascript, how can i get the last character in a string [duplicate]
...rt of the core JavaScript language and may be removed in the future. If at all possible, use the substring() method instead. - From MDN
– Ajeet Shah
May 30 at 21:52
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count the frequency that a value occurs in a dataframe column
...
If you want to apply to all columns you can use:
df.apply(pd.value_counts)
This will apply a column based aggregation function (in this case value_counts) to each of the columns.
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Android Studio - Auto complete and other features not working
I installed android studio.. it was working fine. Now all the sudden, none of the auto complete features are working.. I can type anything anywhere no variable checking, no help with functions or checking anything. I can still compile the project and I get errors when that happens.
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How to delete/create databases in Neo4j?
...s in the graph database Neo4j like in MySQL? Or, at least, how to delete all nodes and relationships of an existing graph to get a clean setup for tests, e.g., using shell commands similar to rmrel or rm ?
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