cy maps in this paper is very simple – much simpler than the wavelet analysis or laskar's (1990， 1993) frequency analysis.
divide the low-pass filtered orbital data into many fragments of the same length. the length of each data segment should be a multiple of 2 in order to apply the fft.
each fragment of the data has a large overlapping part: for example， when the ith data begins from t=ti and ends at t=ti+t， the next data segment ranges from ti+δt≤ti+δt+t， where δt?t. we continue this division until we reach a certain number n by which tn+t reaches the total integration length.
we apply an fft to each of the data fragments， and o
对火星轨道变化问题的最后解释(28/49)