using match-type function to return correctly ordered data from a dataframe

I am regularly running into a problem where I can't seem to figure out
how
maintain correct data order when selecting data out of a dataframe. 
The
below code shows an example of trying to pull data from a dataframe
using
ordered zip codes.  My problem is returning the pulled data in the
correct
order.  This is a very simple example, but it illustrates a regular
problem
that I am running into.

In the past, I have used fairly complicated solutions to pull this off.
There has got to be a more simple and straightforward method ...
probably
some function that I missed in all my googling.

Thanks in advance for anybody's help figuring this out.
~Markus


### Function Definitions ###

# FUNCTION #1 (returns wrong order)
getLatitude1 = function(myzips) {

 # load libraries and data
 library(zipcode)
 data(zipcode)

 # get latitude values
mylats = zipcode[zipcode$zip %in% myzips, "latitude"] #problem is that
this code does not maintain order

 # return data
 return(mylats)
}

# FUNCTION #2 (also returns wrong order)
getLatitude2 = function(myzips) {

 # load libraries and data
 library(zipcode)
 data(zipcode)

 # convert myzips to DF
 myzips = as.data.frame(as.character(myzips))

 # merge in zipcode data based on zip
 results = merge(myzips, zipcode[,c("zip", "latitude")], by.x =
"as.character(myzips)", by.y="zip", all.x=TRUE)

 # return data
 return(results$latitude)
}


### Code ###

# specify a set of zip codes
myzips = c("74432", "72537", "06026", "01085", "65793")

# create a DF
myzips.df = data.frame(zip=myzips, latitude=NA, longitude=NA)

# look at data to determine what should be returned and in what order
library(zipcode)
data(zipcode)
zipcode[zipcode$zip %in% myzips,]

# test function #1 (function definition below)
myzips.df$latitude = getLatitude1(myzips.df$zip) #returns wrong order

# test function #2 (function definition below)
myzips.df$latitude = getLatitude2(myzips.df$zip) #also returns wrong
order



# need "myzips %in% zipcode$zip" to return array/df indices rather than
logical

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