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Change one value based on another value in pandas
...helpful for you.
import pandas
df = pandas.read_csv("test.csv")
df.loc[df.ID == 103, 'FirstName'] = "Matt"
df.loc[df.ID == 103, 'LastName'] = "Jones"
As mentioned in the comments, you can also do the assignment to both columns in one shot:
df.loc[df.ID == 103, ['FirstName', 'LastName']] = 'Matt'...
How do PHP sessions work? (not “how are they used?”)
...re usually stored in, say, /tmp/ on the server, and named sess_{session_id} . I have been looking at the contents and cannot figure out how they really work.
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Laravel Migration Change to Make a Column Nullable
I created a migration with unsigned user_id . How can I edit user_id in a new migration to also make it nullable() ?
9 ...
Can I set enum start value in Java?
...re like classes - and they can even have multiple attributes.
public enum Ids {
OPEN(100), CLOSE(200);
private final int id;
Ids(int id) { this.id = id; }
public int getValue() { return id; }
}
The big difference is that they are type-safe which means you don't have to worry abou...
Why does `a == b or c or d` always evaluate to True?
... == "Kevin" or name == "Jon" or name == "Inbar":
Compose a sequence of valid values, and use the in operator to test for membership:
if name in {"Kevin", "Jon", "Inbar"}:
In general of the two the second should be preferred as it's easier to read and also faster:
>>> import timeit
>&g...
How to retrieve form values from HTTPPOST, dictionary or?
...d controllers. There are good cases for option 2 but I wouldn't encourage wide use.
– Serguei Fedorov
Mar 2 '16 at 15:06
1
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How to query SOLR for empty fields?
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Try this:
?q=-id:["" TO *]
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Show Youtube video source into HTML5 video tag?
I'm trying to put a YouTube video source into the HTML5 <video> tag, but it doesn't seem to work. After some Googling, I found out that HTML5 doesn't support YouTube video URLs as a source.
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How does the compilation/linking process work?
... is usually just declarations), doing replacement of macros (#define), and selecting different portions of text depending of #if, #ifdef and #ifndef directives.
The preprocessor works on a stream of preprocessing tokens. Macro substitution is defined as replacing tokens with other tokens (the opera...
MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback.
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