Median in Easylanguage

[trader273 10]

Was trying to find an easy way to find the median of a given set of numbers. I've searched the pdf files that are available and the only thing remotely close was related to activity bars, so that didnt really help.

 

anyone got an ideas?

[Tams 20]

there is a function named medianprice.

 

it is simply ( H + L ) / 2

[trader273 10]

ok, i guess its just median( )

duh

 

Then I guess what I don't understand is how to get the median of a set of numbers I have.

 

If anyone reads Dr.Steenbarger's blog he showed what he uses for price projections, and I was trying to code something up. I have five variables and I need to take the median of those 5.

[zdo 20]

The Median (or MedianArray) function won't work for you?

[BlowFish 10]

There is some good background here Selection algorithm - Wikipedia, the free encyclopedia.

 

Are you actually talking about price data arriving in real time? That's a wee bit tricky. Trouble with EL is that it's not great for more complex data structures. You could probably sort data into an array as it arrived. Whilst not difficult a bit fiddly.

 

Median is the mid price in a sorted set of numbers right? (not the mid price).

[Tams 20]

ok, i guess its just median( )

duh

 

Then I guess what I don't understand is how to get the median of a set of numbers I have.

 

If anyone reads Dr.Steenbarger's blog he showed what he uses for price projections, and I was trying to code something up. I have five variables and I need to take the median of those 5.

 

you have to use the medianarray

 

first, create an array,

then put the 5 numbers in the array,

then use medianarray to interrogate the array for the median.

[trader273 10]

Ok, I gave this my best shot. I have never used arrays, so this is fun:crap:

 

I searched through TL and some other pdf's.

 

Here is what I got so far:

 

Array:
MyArray[5](0);
ArrayElement[1]=((yesthi-yestlo)/yestop)*100;
ArrayElement[2]=((H2-L2)/O2)*100;
ArrayElement[3]=((H3-L3)/O3)*100;
ArrayElement[4]=((H4-L4)/O4)*100;
ArrayElement[5]=((H5-L5)/O5)*100;

V=MedianArray(myArray,5);

 

 

I have everything defined, and it plots correctly. The error I got is "Index was outsite the bounds of the array"

 

Googled that, and I thought I fixed it but not so much. Probably missing something easy...

[Tams 20]

Array:
MyArray[6](0);

MyArray[1] = ((yesthi-yestlo)/yestop)*100;
MyArray[2] = ((H2-L2)/O2)*100;
MyArray[3] = ((H3-L3)/O3)*100;
MyArray[4] = ((H4-L4)/O4)*100;
MyArray[5] = ((H5-L5)/O5)*100;

Value1 = MedianArray(myArray,6);

 

 

array numbering starts with zero,

but medianarray referencing begins with array element 1.

therefore you need an array of 6 to handle 5 numbers.

Edited April 6, 2010 by Tams

[Tams 20]

more info on array

 

http://www.traderslaboratory.com/forums/f56/array-easylanguage-5785.html

 

[BlowFish 10]

you have to use the medianarray

 

first, create an array,

then put the 5 numbers in the array,

then use medianarray to interrogate the array for the median.

 

This would certainly work but grows exponentially slower as the set of data increases. (It calls SortArray which is a bubble sort and fairly highly iterative). Not a problem if you are looking at (for example) the close of 5 minute bars (small data set) but possibly an issue if you are using say tick data (a large data set).

 

Just offering this for consideration .