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Django Rest Framework File Upload
... very helpful thank you a lot. But i don't understand, why you are converting dict data to QueryDict in parser? In my case in Django, normal dictionary data work perfectly without converting.
– Metehan Gülaç
Apr 12 at 20:15
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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
... 0.0 NaN 0.0
3 0.0 1.0 2.0 3.0
4 NaN 0.0 NaN NaN
If you want to select the rows that have two or more columns with null value, you run the following:
>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
0 1 2 3
1 0.0 NaN 0...
Change Author template in Android Studio
...ferences dialog.
2)In the search box, write "File and Code Templates".
3)Select the left menu item "File and Code Templates".
4)From the middle tabular navigation section, select Includes.
5)Select File Header item that applies to the Java files.
6)You will find an editor section that allow you...
What are the options for storing hierarchical data in a relational database? [closed]
... thought I'd give Celko a bit of competition by coming up with a method to convert an Adjacency List to Nested sets at speeds that just seem impossible. Here's the performance of the push stack method on my i5 laptop.
Duration for 1,000 Nodes = 00:00:00:870
Duration for 10,000 Nodes = 00:01...
What are the differences between the BLOB and TEXT datatypes in MySQL?
...
TEXT and CHAR will convert to/from the character set they have associated with time. BLOB and BINARY simply store bytes.
BLOB is used for storing binary data while Text is used to store large string.
BLOB values are treated as binary strings ...
How can I cast int to enum?
...urEnum is dynamic and will only be known at runtime, and what I want is to convert to Enum?
– Shimmy Weitzhandler
Feb 19 '12 at 9:56
235
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Media Queries: How to target desktop, tablet, and mobile?
...1281px) { /* hi-res laptops and desktops */ }
In practice, many designers convert pixels to ems, largely because ems afford better zooming. At standard zoom 1em === 16px, multiply pixels by 1em/16px to get ems. For example, 320px === 20em.
In response to the comment, min-width is standard in "mobil...
How to select the row with the maximum value in each group
In a dataset with multiple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset:
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Select random lines from a file
...e point is you can keep some lines in memory with shuffle to do the random selection of what to output. Sort is going to sort the entire file, regardless of what your needs are.
– Rubens
Sep 25 '14 at 2:01
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How to deserialize a list using GSON or another JSON library in Java?
... hassle with the Type object, and if you really need a list you can always convert the array to a list, e.g.:
List<Video> videoList = Arrays.asList(videoArray);
IMHO this is much more readable.
In Kotlin this looks like this:
Gson().fromJson(jsonString, Array<Video>::class.java)
...