[R] IF/Else

[Guenther, Cameron]

Hi,
I am trying to write a for loop with if else statements to calculate
biomass density estimates for different types of sampling gear.  
My code is:

bmd=for (i in 1:length(Gear)){
if (Gear==20) {bioden=Biomass/141}
else {if (Gear==23) {bioden=Biomass/68}}
else {if (Gear==160) {bioden=Biomass/4120}}
else {if (Gear==170) {bioden=Biomass/2210}}
else {if (Gear==300) {bioden=Biomass/(DIST_TOW*4*1853)}}
else {if (Gear==301) {bioden=Biomass/(DIST_TOW*4*1853)}}
}

The syntax that is returned is:

> bmd=for (i in 1:length(Gear)){
+ if (Gear==20) {bioden=Biomass/141}
+ else {if (Gear==23) {bioden=Biomass/68}}
+ else {if (Gear==160) {bioden=Biomass/4120}}
Error: syntax error in:
"else {if (Gear==23) {bioden=Biomass/68}}
else"
> else {if (Gear==170) {bioden=Biomass/2210}}
Error: syntax error in "else"
> else {if (Gear==300) {bioden=Biomass/(DIST_TOW*4*1853)}}
Error: syntax error in "else"
> else {if (Gear==301) {bioden=Biomass/(DIST_TOW*4*1853)}}
Error: syntax error in "else"
> }
Error: syntax error in "}"

It appears that the code works for the first two if/else statements and
then fails there after.  Any suggestions?

Cameron Guenther 
Associate Research Scientist
FWC/FWRI, Marine Fisheries Research
100 8th Avenue S.E.
St. Petersburg, FL 33701
(727)896-8626 Ext. 4305
cameron.guenther at myfwc.com