 | 1 | initial version |
Why is the absolute value of the exponential of z:
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
about twice as fast as the exponential of the real part of z:
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
Should I ignore this kind of thing in sage, or is there a good reason in this particular case?
| | 2 | No.2 Revision |
Why is the absolute value of the exponential of z:
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
about twice as fast as the exponential of the real part of z:
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
Should I ignore this kind of thing in sage, or is there a good reason in this particular case?
Here is the data: without fast_callable, these functions take exactly the same amount of time, for example on 4 + 2i they take about 1 second (!!!). With fast_callable, f takes 2.99 µs, and g takes 6.23µs
| | 3 | corrected "second" mistake but the question remains |
Why is the absolute value of the exponential of z:
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
about twice as fast as the exponential of the real part of z:
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
Should I ignore this kind of thing in sage, or is there a good reason in this particular case?
Here is the data: Data:
z = var('z')
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
fs(z) = exp(z).abs()
gs(z) = exp(z.real())
sage: timeit('f(4+2*I)')
625 loops, best of 3: 2.94 µs per loop
without fast_callable, these functions take exactly the same amount sage: timeit('g(4+2I)')
625 loops, best of time, for example on 4 + 2i they take about 1 second (!!!). 3: 5.87 µs per loop
With fast_callable, f takes 2.99 µs, and g takes 6.23µs sage: timeit('fs(4+2I)')
625 loops, best of 3: 1.02 ms per loop
sage: timeit('gs(4+2*I)')
625 loops, best of 3: 988 µs per loop
| | 4 | No.4 Revision |
Why is the absolute value of the exponential of z:
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
about twice as fast as the exponential of the real part of z:
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
Should I ignore this kind of thing in sage, or is there a good reason in this particular case?
Data:
z = var('z')
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
fs(z) = exp(z).abs()
gs(z) = exp(z.real())
sage: timeit('f(4+2*I)')
625 loops, best of 3: 2.94 µs per loop
loop
sage: timeit('g(4+2I)')
timeit('g(4+2*I)')
625 loops, best of 3: 5.87 µs per loop
loop
sage: timeit('fs(4+2I)')
timeit('fs(4+2*I)')
625 loops, best of 3: 1.02 ms per loop
loop
sage: timeit('gs(4+2*I)')
625 loops, best of 3: 988 µs per loop
| | 5 | No.5 Revision |
Why is the absolute value of the exponential of z:
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
about twice as fast as the exponential of the real part of z:
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
Should I ignore this kind of thing in sage, or is there a good reason in this particular case?
Data:
z = var('z')
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
fs(z) = exp(z).abs()
gs(z) = exp(z.real())
sage: timeit('f(4+2*I)')
625 loops, best of 3: 2.94 µs per loop
sage: timeit('g(4+2*I)')
625 loops, best of 3: 5.87 µs per loop
sage: timeit('fs(4+2*I)')
Incidentally, here are the non-fast_callable times: z = var('z') fs(z) = exp(z).abs() gs(z) = exp(z.real()) timeit('fs(4+2*I)')
625 loops, best of 3: 1.02 ms per loop
sage: timeit('gs(4+2*I)')
625 loops, best of 3: 988 µs per loop
| | 6 | No.6 Revision |
Why is the absolute value of the exponential of z:
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
about twice as fast as the exponential of the real part of z:
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
Should I ignore this kind of thing in sage, or is there a good reason in this particular case?
Data:
z = var('z')
f = fast_callable(exp(z).abs(),domain=CDF,vars='z')
g = fast_callable(exp(z.real()), domain=CDF, vars='z')
timeit('f(4+2*I)')
625 loops, best of 3: 2.94 µs per loop
timeit('g(4+2*I)')
625 loops, best of 3: 5.87 µs per loop
Incidentally, here
Non-fast_callable times, in case you
are625 loops, best of 3: 1.02 ms per loop
timeit('gs(4+2*I)')
625 loops, best of 3: 988 µs per loop
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