Can someone please point me towards right direction, my current data looks like this =>

Meter= c( Meter1, Meter 2, Meter 3........Meter 1440)

and for each meter, I have monthly electricity consumption,

Cons=c ( 6623, 11285, 21785....) like this.

I would like to cerate a simple regression model for each meter Meter 1:

```
lm(Cons~ HDD), Meter2: lm( Cons~HDD)----Meter1140=lm( Cons~ HDD )
```

Please see below my code this gives me an error message of

Error in model.frame.default(formula = df$Cons ~ HDD, data = data.subset, : variable lengths differ (found for 'HDD')

Please can you advise where I'm doing wrong

```
mod.store<- list()
unique(df$Meter)
for (i in 1:unique(df$Meter)){
data.subset<-df[df$Meter==unique(df$Meter)[i],]
mod<-lm(df$Cons~HDD,data=data.subset)
mod.store[[i]]<-summary(mod)
}
```

Thanks in advance!