Hice mi primera interpolación connumpy.polyfit () ynumpy.polyval () para 50 valores de longitud para una órbita satelital completa.

Ahora, solo quiero mirar una ventana de 0-4.5 grados de longitud y hacer una segunda interpolación para tener 6,000 puntos de longitud en la ventana.

Necesito usar la ecuación / curva de la primera interpolación para crear la segunda porque solo hay un punto en el rango de la ventana. No estoy seguro de cómo hacer la segunda interpolación.

Entradas:

lon = [-109.73105744378498, -104.28690174554579, -99.2435132929552, -94.48533149079628, -89.91054414962821, -85.42671400689177, -80.94616150449806, -76.38135021210172, -71.6402674905218, -66.62178379632216, -61.21120467960157, -55.27684029674759, -48.66970878028004, -41.23083703244677, -32.813881865289346, -23.332386757370532, -12.832819226213942, -1.5659455609661785, 10.008077792630402, 21.33116444634303, 31.92601575632583, 41.51883213364072, 50.04498630545507, 57.58103957109249, 64.26993028992476, 70.2708323505337, 75.73441871754586, 80.7944079829813, 85.56734813043659, 90.1558676264546, 94.65309120129724, 99.14730128118617, 103.72658922048785, 108.48349841714494, 113.51966824008079, 118.95024882101737, 124.9072309203375, 131.5395221402974, 139.00523971191907, 147.44847902856114, 156.95146022590976, 167.46163867248032, 178.72228750873975, -169.72898181991064, -158.44642409799974, -147.8993300787564, -138.35373014113995, -129.86955508919888, -122.36868103811106, -115.70852432245486]

myOrbitJ2000Time = [ 20027712.,  20027713.,  20027714.,  20027715.,  20027716.,
        20027717.,  20027718.,  20027719.,  20027720.,  20027721.,
        20027722.,  20027723.,  20027724.,  20027725.,  20027726.,
        20027727.,  20027728.,  20027729.,  20027730.,  20027731.,
        20027732.,  20027733.,  20027734.,  20027735.,  20027736.,
        20027737.,  20027738.,  20027739.,  20027740.,  20027741.,
        20027742.,  20027743.,  20027744.,  20027745.,  20027746.,
        20027747.,  20027748.,  20027749.,  20027750.,  20027751.,
        20027752.,  20027753.,  20027754.,  20027755.,  20027756.,
        20027757.,  20027758.,  20027759.,  20027760.,  20027761.]

Código:

deg = 30 #polynomial degree for fit
fittime = myOrbitJ2000Time - myOrbitJ2000Time[0]

'Longitude Interpolation'
fitLon = np.polyfit(fittime, lon, deg)   #gets fit coefficients
polyval_lon = np.polyval(fitLon,fittime) #interp.s to get actual values


'Get Longitude values for a window of 0-4.5 deg Longitude'
lonwindow =[]

for i in range(len(polyval_lon)):
    if 0 < polyval_lon[i] < 4.5:         # get lon vals in window
        lonwindow.append(polyval_lon[i]) #append lon vals

lonwindow = np.array(lonwindow)