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How to extract text from a PDF? [closed]
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I was given a 400 page pdf file with a table of data that I had to import - luckily no images. Ghostscript worked for me:
gswin64c -sDEVICE=txtwrite -o output.txt input.pdf
The output file was split into pages with headers, etc., but it was then easy to write a...
UITableView + Add content offset at top
I need to add some blank space to the top of my UITableView that does not affect the size of the content area. Shifting the content down or adding a blank cell is NOT what I want to do. Instead I just want an offset.
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Rails migrations: self.up and self.down versus change
... you rollback? Of course it's remove_column. What is the inverse of create_table? It's drop_table. So in these cases rails know how to rollback and define a down method is superfluous (you can see in the documentation the methods currently supported from the change method).
But pay attention becaus...
Django dump data for a single model?
...Django dumpdata management command allows you to dump data from individual tables:
./manage.py dumpdata myapp1 myapp2.my_model
You can also separate multiple apps and models on the command line. Here's the canonical definition:
django-admin dumpdata [app_label[.ModelName] [app_label[.ModelName] ...
Difference between “read commited” and “repeatable read”
..., will find the Same data, data is free to change after it was read.
Repeatable read is a higher isolation level, that in addition to the guarantees of the read committed level, it also guarantees that any data read cannot change, if the transaction reads the same data again, it will find the previ...
How do I replace NA values with zeros in an R dataframe?
...the complete results.
If you are struggling with massive dataframes, data.table is the fastest option of all: 40% faster than the standard Base R approach. It also modifies the data in place, effectively allowing you to work with nearly twice as much of the data at once.
A clustering of other he...
iOS 7 TableView like in Settings App on iPad
I want to have a group UITableView with the style same like the iPad Settings application Detail view for iOS 7 .
15 Ans...
How does Go compile so quickly?
...ded to be fast: it should take at most a few seconds to build a large executable on a single computer. To meet these goals required addressing a number of linguistic issues: an expressive but lightweight type system; concurrency and garbage collection; rigid dependency specification; and so on. FAQ
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How to add a footer to a UITableView in Storyboard
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You can just drag a view to the bottom area of the tableView. You'll see in the hierarchy that it will be a subview of the tableview. You can then drag subviews such as labels and buttons there, adjust the height, etc.
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What does SQL clause “GROUP BY 1” mean?
...d name, you may also group by ordinal, or position of the field within the table. 1 corresponds to the first field (regardless of name), 2 is the second, and so on.
This is generally ill-advised if you're grouping on something specific, since the table/view structure may change. Additionally, it ma...