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Generate a random letter in Python
Is there a way to generate random letters in Python (like random.randint but for letters)? The range functionality of random.randint would be nice but having a generator that just outputs a random letter would be better than nothing.
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Call apply-like function on each row of dataframe with multiple arguments from each row
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You can apply apply to a subset of the original data.
dat <- data.frame(x=c(1,2), y=c(3,4), z=c(5,6))
apply(dat[,c('x','z')], 1, function(x) sum(x) )
or if your function is just sum use the vectorized version:
rowSums(dat[,c('x','z')])
[1] 6 8...
Get unique values from a list in python [duplicate]
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First declare your list properly, separated by commas. You can get the unique values by converting the list to a set.
mylist = ['nowplaying', 'PBS', 'PBS', 'nowplaying', 'job', 'debate', 'thenandnow']
myset = set(mylist)
print(myset)
If you use it further as a list,...
Why does comparing strings using either '==' or 'is' sometimes produce a different result?
I've got a Python program where two variables are set to the value 'public' . In a conditional expression I have the comparison var1 is var2 which fails, but if I change it to var1 == var2 it returns True .
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LINQPad [extension] methods [closed]
...s two extension methods (in LINQPad.Extensions), namely Dump() and Disassemble(). Dump() writes to the output window using LINQPad's output formatter and is overloaded to let you specify a heading:
typeof (int).Assembly.Dump ();
typeof (int).Assembly.Dump ("mscorlib");
You can also specify a maxi...
With arrays, why is it the case that a[5] == 5[a]?
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The C standard defines the [] operator as follows:
a[b] == *(a + b)
Therefore a[5] will evaluate to:
*(a + 5)
and 5[a] will evaluate to:
*(5 + a)
a is a pointer to the first element of the array. a[5] is the value that's 5 elements further from a, which is the same as *(...
How to wrap async function calls into a sync function in Node.js or Javascript?
Suppose you maintain a library that exposes a function getData . Your users call it to get actual data:
var output = getData();
Under the hood data is saved in a file so you implemented getData using Node.js built-in fs.readFileSync . It's obvious both getData and fs.readFileSync are sy...
Should you choose the MONEY or DECIMAL(x,y) datatypes in SQL Server?
I'm curious as to whether or not there is a real difference between the money datatype and something like decimal(19,4) (which is what money uses internally, I believe).
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How to compare types
...eld and I want to know if it is System.String , System.DateTime , etc., but typeField.Equals(System.String) doesn't work.
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How can I tell if I'm running in 64-bit JVM or 32-bit JVM (from within a program)?
How can I tell if the JVM in which my application runs is 32 bit or 64-bit? Specifically, what functions or properties I can used to detect this within the program?
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