Programmer Guide/Command Reference/EVAL/wsum: Difference between revisions
From STX Wiki
< Programmer Guide | Command Reference | EVAL
Jump to navigationJump to search
No edit summary |
No edit summary |
||
Line 1: | Line 1: | ||
{{DISPLAYTITLE:{{SUBPAGENAME}}}} | {{DISPLAYTITLE:{{SUBPAGENAME}}}} | ||
Calculate the weighted sum over one or more user-defined extents of a function <var>y = f(x)</var>. Depending on the number of extents, the result of the function is a vector or a scalar. | Calculate the weighted sum over one or more user-defined extents of a function <var>y = f(x)</var>. Depending on the number of extents, the result of the function is a vector or a scalar. |
Revision as of 12:19, 8 April 2011
Calculate the weighted sum over one or more user-defined extents of a function y = f(x). Depending on the number of extents, the result of the function is a vector or a scalar.
- Usage
wsum(x, y, w, s, us, os, n)
sum(x, y, w, s, uv, ov)
sum(x, y, w, s, rv)
sum(x, y, w, s, rm)
- x, y
- the x- and y-data vector; y[i] = f(x[i])
- wdefines the type of the weighting function
- {class="keinrahmen"
|w=0 ||no weight (rectangle) |- |w=1 ||triangle |- |w=2 ||hanning window |- |w=2 ||hamming window |}
- sif this argument is set to 1 the sum of each extent is normalized (scaled by
1/sum(weights)
), otherwise not
- sif this argument is set to 1 the sum of each extent is normalized (scaled by
- Note: an extent is defined by the x-range {xmin, xmax} and not by the indices!
- us, os, n
- us is the lowest x-value, os the highest and n the number of extents. All three arguments are scalars. Every pair
{'us'+d*k, us+d*(k+1)} (with: d=(os-us)/n, k=0..n-1)
defines an extent to sum. - uv, ov
- Every pair
{uv[k], ov[k]} (with k=0..nrow(uv)-1)
defines an extent to sum. Both arguments must be vectors with same length. - rv
- Every pair
{rv[k], rv[k+1]} (with k=0..nrow(rv)-2)
defines an extent to sum. The argument must be vector. - rm
- Every pair
{rm[k,0], rm[k,1]} (with k=0..nrow(rm)-1)
defines an extent to sum. The argument must be matrix with 2 columns.
- Result
- The result r is a scalar or a vector. Each element ri is the sum of weighted the y values over the i-th extent {xmini, xmax<sub}.