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Is there a NumPy function to return the first index of something in an array?
...mensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so would
array[itemindex[0][1]][itemindex[1][1]]
numpy.where
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Which is faster in Python: x**.5 or math.sqrt(x)?
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math.sqrt(x) is significantly faster than x**0.5.
import math
N = 1000000
%%timeit
for i in range(N):
z=i**.5
10 loops, best of 3: 156 ms per loop
%%timeit
for i in range(N):
z=math.sqrt(i)
10 loops, best of 3: 91.1 ms per loop
Using Python 3.6....
How to make link look like a button?
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107
Using CSS:
.button {
display: block;
width: 115px;
height: 25px;
backg...
How can I convert a DateTime to the number of seconds since 1970?
...ateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
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leading zeros in rails
...eld, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the min field if the user enter "0" it should put in as "00".
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MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...4) zerofill
both columns has the value of 1, output for column A would be 01 and 0001 for B, as seen in screenshot below :)
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What is the difference between 127.0.0.1 and localhost
... still have to do an actual lookup of localhost somewhere.
If you use 127.0.0.1, then (intelligent) software will just turn that directly into an IP address and use it. Some implementations of gethostbyname will detect the dotted format (and presumably the equivalent IPv6 format) and not do a looku...
Converting strings to floats in a DataFrame
...) or pd.to_numeric as described in other
answers.
This is available in 0.11. Forces conversion (or set's to nan)
This will work even when astype will fail; its also series by series
so it won't convert say a complete string column
In [10]: df = DataFrame(dict(A = Series(['1.0','1']), B = Series...
.NET String.Format() to add commas in thousands place for a number
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String.Format("{0:n}", 1234); // Output: 1,234.00
String.Format("{0:n0}", 9876); // No digits after the decimal point. Output: 9,876
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Minimizing NExpectation for a custom distribution in Mathematica
...f we plot pdf2 it looks exactly as your Plot
Plot[pdf2[3.77, 1.34, -2.65, 0.40, x], {x, 0, .3}]
Now to the expected value. If I understand it correctly we have to integrate x * pdf[x] from -inf to +inf for a normal expected value.
x * pdf[x] looks like
Plot[pdf2[3.77, 1.34, -2.65, 0.40, x]*x...