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How to name variables on the fly?
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And this option?
list_name<-list()
for(i in 1:100){
paste("orca",i,sep="")->list_name[[i]]
}
It works perfectly. In the example you put, first line is missing, and then gives you the error message.
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Why does MYSQL higher LIMIT offset slow the query down?
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FROM mytable
ORDER BY
id
LIMIT 10000, 30
) q
JOIN mytable t
ON t.id = q.id
See this article:
MySQL ORDER BY / LIMIT performance: late row lookups
share
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How to delete a row by reference in data.table?
...something like this:
DT = data.table(col1 = 1:1e6)
cols = paste0('col', 2:100)
for (col in cols){ DT[, (col) := 1:1e6] }
keep.idxs = sample(1e6, 9e5, FALSE) # keep 90% of entries
DT.subset = data.table(col1 = DT[['col1']][keep.idxs]) # this is the subsetted table
for (col in cols){
DT.subset[, (c...
How to get line count of a large file cheaply in Python?
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I am working with 100Gb+ files, and your rawgencounts is the only feasible solution I have seen so far. Thanks!
– soungalo
Nov 10 '15 at 11:47
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Using semicolon (;) vs plus (+) with exec in find
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Charlie MartinCharlie Martin
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Java multiline string
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100
This is an old thread, but a new quite elegant solution (with only 4 maybe 3 little drawbacks)...
CharSequence VS String in Java?
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100
But keep in mind this caveat from the CharSequence javadoc: This interface does not refine the general contracts of the equals and hashCod...
Convert Unicode to ASCII without errors in Python
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100
Use unidecode - it even converts weird characters to ascii instantly, and even converts Chines...
Remove leading or trailing spaces in an entire column of data
...'.
Set a break line so the longest text will fit. If your largest cell
has 100 characters you can set the breakline on 200 or whatever you
want.
Finish the operation.
You can now delete the new column Excel has created.
The 'side-effect' is that Excel has removed all trailing spaces in the origina...
SparseArray vs HashMap
...ere is an example of SparseIntArray vs HashMap<Integer, Integer> for 1000 elements:
SparseIntArray:
class SparseIntArray {
int[] keys;
int[] values;
int size;
}
Class = 12 + 3 * 4 = 24 bytes
Array = 20 + 1000 * 4 = 4024 bytes
Total = 8,072 bytes
HashMap:
class HashMap<K, V...