Sage Reference Manual: Quantitative Finance - Mirrors

Sage Reference Manual: Quantitative Finance, Release 6.1.1
scale(s)
Return new time series obtained by multiplying every value in the series by s.
INPUT:
•s – a float.
OUTPUT:
A new time series with all values multiplied by s.
EXAMPLES:
sage: v = finance.TimeSeries([5,4,1.3,2,8,10,3,-5]); v
[5.0000, 4.0000, 1.3000, 2.0000, 8.0000, 10.0000, 3.0000, -5.0000]
sage: v.scale(0.5)
[2.5000, 2.0000, 0.6500, 1.0000, 4.0000, 5.0000, 1.5000, -2.5000]
scale_time(k)
Return the new time series at scale k. If the input time series is X 0 , X 1 , X 2 , . . . , then this function returns
the shorter time series X 0 , X k , X 2k , . . . .
INPUT:
•k – a positive integer.
OUTPUT:
A new time series.
EXAMPLES:
sage: v = finance.TimeSeries([5,4,1.3,2,8,10,3,-5]); v
[5.0000, 4.0000, 1.3000, 2.0000, 8.0000, 10.0000, 3.0000, -5.0000]
sage: v.scale_time(1)
[5.0000, 4.0000, 1.3000, 2.0000, 8.0000, 10.0000, 3.0000, -5.0000]
sage: v.scale_time(2)
[5.0000, 1.3000, 8.0000, 3.0000]
sage: v.scale_time(3)
[5.0000, 2.0000]
sage: v.scale_time(10)
[]
A series of odd length:
sage: v = finance.TimeSeries([1..5]); v
[1.0000, 2.0000, 3.0000, 4.0000, 5.0000]
sage: v.scale_time(2)
[1.0000, 3.0000, 5.0000]
TESTS:
sage: v.scale_time(0)
Traceback (most recent call last):
...
ValueError: k must be positive
sage: v.scale_time(-1)
Traceback (most recent call last):
...
ValueError: k must be positive
show(*args, **kwds)
Calls plot and passes all arguments onto the plot function. This is thus just an alias for plot.
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