Displaying 1 result from an estimated 1 matches for "sine_nls".
2011 Dec 11
1
nls start values
...963610,
1.884184, 1.955160, 1.801175, 1.829686, 1.773260, 1.588768, 1.563774,
1.559192)
tpoints <-
c(0,0,0,2,2,2,4,4,4,6,6,6,8,8,8,12,12,12,14,14,14,16,16,16,18,18,18,20,20,20,24,24,24)
shift=mean(gene_expression) # y-axis (expression) shift
# Perfect fit
startvals <- list(phase=pi, amp=0.5)
sine_nls <- nls(gene_expression ~ sin(tpoints * afreq + phase) * amp +
shift, start=startvals, algorithm="port", lower=lowervals, upper=uppervals)
# Convergence failure
startvals <- list(phase=0, amp=0.5)
sine_nls <- nls(gene_expression ~ sin(tpoints * afreq + phase) * amp +
shift, start...