I'd like to define a CustomFactor that looks at the prices for all available dates before the current timestamp and tries to compute some output. Is there a way to do this? It seems like I can only specific a static value for window_length when I define my CustomFactor. Can I get around it by just specifying a very high window length, like 10000?
Ex:
Time Price
2002/1/1 45.4
2002/1/2 42.4
2002/1/3 41.4
2002/1/4 41.4
...
2011/1/1 125.5
At 2002/1/1, I'd like the window_length = 0
At 2002/1/2, I'd like the window_length = 1
At 2002/1/3, I'd like the window_length = 2
At 2002/1/4, I'd like the window_length = 3
so on and so forth. At 2011/1/1, I'd like the window_length = I guess 365 * 10 years.