Manuals/calci/TREND

TREND(y,x,x1,c)

Description

This function calculating the trend line using the given set of $y$ and $x$ values.
Trend line is the straight line which joins two or more points in the upward direction.
It is calculating using the equation $y=mx+b$ ,which is the simple equation for the straight line.
In this equation $x$ is the independent variable, $y$ is the dependent variable, $m$ is the slope of the line and $b$ is the constant which is equal to $y$ when $x=0$ .
In $TREND(y,x,x_{1},c)$ , $y$ is the set of y-values to find the linear trend, $x$ is the set of x- values to find the linear trend, $x_{1}$ is the set of new x-values for which the function calculates corresponding new y-values and $c$ is the constant.
It is either TRUE or FALSE. If c value is TRUE or omitted, then it is calculated normally.
If $c$ value is FALSE, then $c=0$ , and $y=mx$ . Here $y$ is required. $x$ , $x_{1}$ and $c$ are optional.
If $x$ value is omitted, then it is assumed to be the array{1,2,3..} which is the same size of $y$ . If $x_{1}$ value is omitted, then it is assumed to be the same size of $x$ .
If both $x$ and $x_{1}$ are omitted, then they are assumed to be the array {1,2,3..} which is the same size of y.
$TREND$ function is used for polynomial curve fitting by regressing against the same variable raised to different powers.
When entering an array constant for an argument such as $x$ , use commas to separate values in the same row and semicolons to separate rows.