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Difference between map, applymap and apply methods in Pandas
...taframe is only modified by either reassigning df = modified_df or if you set inplace=True flag. Also dataframe will change if you pass a dataframe to a function by reference and the function modifies the dataframe
– muon
Apr 13 '16 at 16:30
...
Python __str__ and lists
In Java, if I call List.toString(), it will automatically call the toString() method on each object inside the List. For example, if my list contains objects o1, o2, and o3, list.toString() would look something like this:
...
What are the most interesting equivalences arising from the Curry-Howard Isomorphism?
...me upon the Curry-Howard Isomorphism relatively late in my programming life, and perhaps this contributes to my being utterly fascinated by it. It implies that for every programming concept there exists a precise analogue in formal logic, and vice versa. Here's a "basic" list of such analogies, of...
Android - border for button
...917" />
</shape>
And add button to your XML activity layout and set background android:background="@drawable/button_border".
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/button_border"
android:text="Butto...
Get the name of an object's type
...tor property that points to Object, not Thingy. So we fall right at the outset; you simply cannot trust constructor in a codebase that you don't control.
Multiple Inheritance
An example where it isn't as obvious is using multiple inheritance:
function a() { this.foo = 1;}
function b() { this.bar = 2...
MySQL load NULL values from CSV data
...o what you want. It reads the fourth field into a local variable, and then sets the actual field value to NULL, if the local variable ends up containing an empty string:
LOAD DATA INFILE '/tmp/testdata.txt'
INTO TABLE moo
FIELDS TERMINATED BY ","
LINES TERMINATED BY "\n"
(one, two, three, @vfour, f...
What is Data Transfer Object?
...ue however that this is ok if it's semantically correct (say if you pass a settings class with properties rather than the properties themselves as values). What you shouldn't do is throw in all the arguments for the sake of passing a single object, since they may very well be unrelated and cause nig...
Rollback a Git merge
...ou do a fast-forward merge, the second one you describe, you can use git reset to get back to the previous state:
git reset --hard <commit_before_merge>
You can find the <commit_before_merge> with git reflog, git log, or, if you're feeling the moxy (and haven't done anything else): gi...
ssh: The authenticity of host 'hostname' can't be established
...
Depending on your ssh client, you can set the StrictHostKeyChecking option to no on the command line, and/or send the key to a null known_hosts file. You can also set these options in your config file, either for all hosts or for a given set of IP addresses or ho...
Printing Lists as Tabular Data
... If the data in the body is larger than the headers, you can set column width based on the first row of data. for t in data[0]: ...