DADiSP Worksheet Functions > F - K > IDXTOX
Converts index values of a series to X values.
IDXTOX(series, idx)
series |
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An input series |
idx |
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An integer or a series of integers. The indices ranging from SPL_START_INDEX (usually 1) to length(s). |
A real or series.
W1: 1..0.1..10
W2: idxtox(W1, 1..6)
W2 contains the series {1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6}, the first 6 X values of W1.
W3: gsin(10, .1, 1)
idxto(W3, 2)
returns 0.1, the second X value of series.
Indices start at 1 unless STARTINDEX is invoked or the SPL_START_INDEX configuration parameter is set.
For XY or XYZ series, the indices are looked up and the closest matches are returned.
For interval series, the X values are computed as follows:
x = (idx - start) * deltax(s) + xoffset(s)
where start is the value of STARTINDEX or SPL_START_INDEX (usually 1).