Subversion Repositories wimsdev

!goto $wims_read_parm

:def

title=Data median

synonyme=statistic median, median of statistics

input=data1d

!exit

:proc

cnt=!itemcnt $formula

fml=

!for i=1 to $cnt

 t=!item $i of $formula

 fml=!append item $[$t] to $fml

!next i

fml=!sort numeric item $fml

!if $[$cnt%2]=1

 result=!item $[($cnt+1)/2] of $fml

!else

 t1=!item $[$cnt/2] of $fml

 t2=!item $[$cnt/2+1] of $fml

 result=$[($t1+$t2)/2]

!endif

!exit

:output

<p class="wimscenter">

Median =

!htmlmath $result

</p>

Data: $cnt numbers { $formula }

<p>

The <em>median</em> of sorted data 

\(\{x_1, x_2, ..., x_n\}\) 

is equal to

!set ins_align=middle

!insmath \frac{x_{n/2}+x_{n/2+1}}{2}

 when \(n\) is even, or to \(x_{\frac{n+1}{2}}\)

when \(n\) is odd.

</p>

!exit