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How to get a subset of a javascript object's properties
Say I have an object:
25 Answers
25
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Removing leading zeroes from a field in a SQL statement
I am working on a SQL query that reads from a SQLServer database to produce an extract file. One of the requirements to remove the leading zeroes from a particular field, which is a simple VARCHAR(10) field. So, for example, if the field contains '00001A', the SELECT statement needs to return the...
How to keep index when using pandas merge
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In [5]: a.reset_index().merge(b, how="left").set_index('index')
Out[5]:
col1 to_merge_on col2
index
a 1 1 1
b 2 3 2
c 3 4 NaN
Note that for some left merge operations, you may en...
Difference between binary semaphore and mutex
Is there any difference between a binary semaphore and mutex or are they essentially the same?
34 Answers
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In MySQL, how to copy the content of one table to another table within the same database?
...uld like to insert to a table from another table. Is there easy way of doing this?
8 Answers
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How do I put variables inside javascript strings?
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If you want to have something similar, you could create a function:
function parse(str) {
var args = [].slice.call(arguments, 1),
i = 0;
return str.replace(/%s/g, () => args[i++]);
}
Usage:
s = parse('hello %s, how are you doing...
Opposite of %in%: exclude rows with values specified in a vector
A categorical variable V1 in a data frame D1 can have values represented by the letters from A to Z. I want to create a subset D2, which excludes some values, say, B, N and T. Basically, I want a command which is the opposite of %in%
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Order data frame rows according to vector with specific order
...cording to a "target" vector as the one I implemented in the short example below?
5 Answers
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How to remove the first Item from a list?
...st [0, 1, 2, 3, 4] I'd like to make it into [1, 2, 3, 4] . How do I go about this?
10 Answers
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Get selected value/text from Select on change
I need to get the value of the selected option in javascript: does anyone know how to get the selected value or text, please tell how to write a function for it. I have assigned onchange() function to select so what do i do after that?
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