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How to save a data.frame in R?
...ta.Rda")
Then load it with:
load("data.Rda")
You could also use write.table() or something like that to save the table in plain text, or dput() to obtain R code to reproduce the table.
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What is the most ridiculous pessimization you've seen? [closed]
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Databases are pessimization playland.
Favorites include:
Split a table into multiples (by date range, alphabetic range, etc.) because it's "too big".
Create an archive table for retired records, but continue to UNION it with the production table.
Duplicate entire databases by (division/cus...
Reset Entity-Framework Migrations
...e the migrations folder in your project; And
Delete the __MigrationHistory table in your database (may be under system tables); Then
Run the following command in the Package Manager Console:
Enable-Migrations -EnableAutomaticMigrations -Force
Use with or without -EnableAutomaticMigrations
And fin...
Fastest Way to Find Distance Between Two Lat/Long Points
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Create your points using Point values of Geometry data types in MyISAM table. As of Mysql 5.7.5, InnoDB tables now also support SPATIAL indices.
Create a SPATIAL index on these points
Use MBRContains() to find the values:
SELECT *
FROM table
WHERE MBRContains(LineFromText(CONCAT(
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Replace all 0 values to NA
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What would the equivalent syntax be for a data.table object?
– itpetersen
Dec 7 '14 at 5:33
6
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“’” showing on page instead of “ ' ”
...h is being decoded as CP-1252 instead of UTF-8. If you check the encodings table, then you see that this character is in UTF-8 composed of bytes 0xE2, 0x80 and 0x99. If you check the CP-1252 code page layout, then you'll see that each of those bytes stand for the individual characters â, € and ...
How do I specify unique constraint for multiple columns in MySQL?
I have a table:
14 Answers
14
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What is the difference between MOV and LEA?
...is answer is basically wrong because the question is asking about MOV AX, [TABLE-ADDR], which is a load. So there is a major difference. The equivalent instruction is mov ax, OFFSET table_addr
– Peter Cordes
Feb 27 '18 at 23:56
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Quick Way to Implement Dictionary in C
...ection 6.6 of The C Programming Language presents a simple dictionary (hashtable) data structure. I don't think a useful dictionary implementation could get any simpler than this. For your convenience, I reproduce the code here.
struct nlist { /* table entry: */
struct nlist *next; /* next ent...
Correct way to use StringBuilder in SQL
...ink you've misquoted it, though; surely there aren't quotes around id2 and table?)
Note that the aim (usually) is to reduce memory churn rather than total memory used, to make life a bit easier on the garbage collector.
Will that take memory equal to using String like below?
No, it'll cause m...