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 8: | Line 8: | ||
:'''<code>sum(<var>x</var>, <var>y</var>, <var>w</var>, <var>s</var>, <var>rm</var>)</code>''' | :'''<code>sum(<var>x</var>, <var>y</var>, <var>w</var>, <var>s</var>, <var>rm</var>)</code>''' | ||
:;<var>x, y</var>: the x- and y-data vector; y[i] = f(x[i]) | :;<var>x, y</var>: the x- and y-data vector; y[i] = f(x[i]) | ||
:;<var>w</var>defines the type of the weighting function | :;<var>w</var>: defines the type of the weighting function | ||
::{|class="keinrahmen" | ::{|class="keinrahmen" | ||
|''w''=0 ||no weight (rectangle) | |''w''=0 ||no weight (rectangle) | ||
| Line 18: | Line 18: | ||
|''w''=2 ||hamming window | |''w''=2 ||hamming window | ||
|} | |} | ||
:;<var>s</var>if this argument is set to '''1''' the sum of each extent is normalized (scaled by <code>1/sum(weights)</code>), otherwise not | :;<var>s</var>: if this argument is set to '''1''' the sum of each extent is normalized (scaled by <code>1/sum(weights)</code>), otherwise not | ||
:Note: an extent is defined by the x-range {xmin, xmax} and not by the indices! | :Note: an extent is defined by the x-range {xmin, xmax} and not by the indices! | ||
:;<var>us, os, n</var>: ''us'' is the lowest x-value, ''os'' the highest and ''n'' the number of extents. All three arguments are scalars. Every pair <code>{'us'+d*k, ''us''+d*(k+1)} (with: d=(''os''-''us'')/n, k=0..n-1)</code> defines an extent to sum. | :;<var>us, os, n</var>: ''us'' is the lowest x-value, ''os'' the highest and ''n'' the number of extents. All three arguments are scalars. Every pair <code>{'us'+d*k, ''us''+d*(k+1)} (with: d=(''os''-''us'')/n, k=0..n-1)</code> defines an extent to sum. | ||
Revision as of 12:20, 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])
- w
- defines the type of the weighting function
w=0 no weight (rectangle) w=1 triangle w=2 hanning window w=2 hamming window
- s
- if this argument is set to 1 the sum of each extent is normalized (scaled by
1/sum(weights)), otherwise not
- 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}.
