Here's one effort to formulate RSI, based on the formula:
rsi:= 100-(100/(1+rs));
The scan is below, but it doesn't give values matching those in QP's data window, Wow and Metastock. I thought the problem might be that it's only calculating average price changes on up and down days, but not a moving average of average price changes on up down days, but I tried it with the moving average, too, and that scan didn't give the right values, either. The scans are:
output = "ma.lst";
input = "portfoli.lst";
daystoload=2000;
issuetype=common;
exchange nyse,nasdaq,amex;
float plus, minus, newrsi, rs;
integer i;
plus:=0;
minus:=0;
for i = 0 to -13 step -1 do
if close(i)>close(i-1) then
plus:= plus + (close(i)-close(i-1))/14;
endif;
if close(i) < close(i-1) then
minus:= minus + abs(close(i)-close(i-1))/14;
endif;
next i;
rs:=plus/(minus+.000000001);
newrsi:= 100-(100/(1+rs));
println Symbol:-6,",", "Plus: ", plus, "Minus: ", minus:6:3, "Newrsi: ", newrsi:6:3;
***********************
The next scan is basically the same, except for the fact that it calculates moving averages of average price changes on up and down days (moving averages of "plus" and "minus").
output="ma.lst";
input="portfoli.lst";
daystoload=500;
issuetype=common;
exchange nyse,nasdaq,amex;
float plus, minus, newrsi, rs;
integer i, d;
plus:=0;
minus:=0;
for d = 0 to 13 step 1 do
for i = (0) to (-13) step -1 do
if close(i)>close(i-1) then
plus:= plus + (close(i)-close(i-1));
endif;
if close(i) < close(i-1) then
minus:= minus + abs(close(i)-close(i-1));
endif;
next i;
next d;
rs:=plus/(minus+.000000001);
newrsi:= 100-(100/(1+rs));
println Symbol:-6,",", "Plus: ", plus, "Minus: ", minus:6:3, "Newrsi: ", newrsi:6:3;
***************************
The moving average of average price changes amounts to a moving average of a moving average. The formula I used for that is below. I checked this formula for an MA of an MA with closing prices, and compared it to the results from this formula in Wow and Metastock: mov(mov(c,14,s),14,s). The values are the same. Here's the formula:
output = "moma.lst";
//moving average of moving average, by Brooke
daystoload=2000;
issuetype=common;
exchange nyse,nasdaq,amex;
float ma, moma, period;
integer i, d;
period:=14;
ma:=0;
for d = 0 to period-1 step 1 do
for i = (0-d) to (-(period-1)-d) step -1 do
ma:= ma + close(i)/period;
moma:=ma/period;
next i;
next d;
println Symbol:-6,",", "Moving average of moving average: ", moma; |
