Why is `merge()` producing an empty object?

lodash merge empty array
lodash merge objects
lodash merge arrays
lodash merge vs object assign
lodash mergewith
lodash deep merge
lodash compare objects
lodash differenceby

I have subset a data frame by species using which():

sp1 <- data[which(data$species=='sp1'),]

There are data for 4 sites in this subset data frame (sp1), and I would like to pull out the data from two of them and combine them into a a new data frame.

I subset them out using which() again:

site.1 <- data.frame(sp1[which(sp1$site=='site1'),]) site.2 <- data.frame(sp1[which(sp1$site=='site2'),])

However, when I use merge() to combine them into a new data frame:

site.1.2 <- merge(site.1,site.2, by = "site")

R produces an empty data frame (with the correct headers).

My questions are:

1) Why isn't merge() putting the data from site.1 and site.2 into this new data frame?

2) Could I simply subset the data from site1 and site2 out of the original data frame together? If so, how? I have tried to use which() with an OR statement:

site.1.2 <- data.frame(data[which(data$site=='site1'),] | data[which(data$site=='site1'),])

but this was not successful.

merge isn't working because it is looking to match site being equal in the two data sets, you could do it by doing it by = "all other columns" maybe

the easiest way to do what you want would be

site.1.2 <- sp1[sp1$Site %in% c("site1", "site2"), ]

may need some slight alterations, didn't use a dummy set to check as not provided

edit: sp1$ required since not data.table

ECOOP 2013 -- Object-Oriented Programming: 27th European , Decoration combinator derived from merge and empty Unfortunately, it is still =​>A and an object algebra ExpAlg[A] and produces a wrapped object algebra of  Merging two data.frame objects while preserving the rows’ order Merging two data.frame objects in R is very easily done by using the merge function. While being very powerful, the merge function does not (as of yet) offer to return a merged data.frame that preserved the original order of, one of the two merged, data.frame objects.

I am no t sure if I understand what do you really want as output, but I suspect you want a dataframe for species == sp1 with data of the two sites.

If I am correct you should do the merge by species not by site, like as follow:

site.1.2 <- merge(site.1,site.2, by = "species")

If not, and you want to merge by site you should do :

site.1.2 <- merge(site.1,site.2, by = "site", all=T)

Hope it helps.

The Unity of Linguistic Meaning, 5.3.2 The syntax of Merge: heads and hierarchy The moral of the previous section to produce further merged objects ad infinitum, where each object displays its We can, however, exclude the latter sets, for the empty set is uninterpretable  N-number of dimension objects can be merged between 2 Queries provided the objects have the same data type. Note : 'Data type' means STRING, NUMBER, DATE etc. While merging the dimension objects it should be kept in mind that if the 2 objects to be merged are of same type and value but the values are of different case (Lower Case & Upper Case) then the values will be treated as 2 distinct values.

A very simple solution:


Beyond jQuery, The ability to merge two objects is possible without jQuery as well method, we can simply declare the first parameter (the “target” object) to be an empty object. extend function we wrote earlier can be used to produce the exact same result. >Is it possible to merge the empty cell beside "A" and "BELL" into the cells where "A" and BELL are so that both are centered above the "Start" and "Finish" cells? The "A" and "BELL" cells are actual fields - they were not manually typed in. Try these steps: 1. Create a break on the variable that includes A and BELL.

The Complete Guide to Blender Graphics: Computer Modeling & , We can combine a sound file “F Curve” and a “Cast” modifier with an “Empty” control object to produce an animation of the “Plane” surface deformation. Merge Dimension. This is a feature in Web Intelligence which allows linking of two or more data providers( queries). Basically we merge objects from two or more queries in one webi report, so that we can use them in same block. Mandatory condition to merge objects is to have same data type. For eg.

The Adaptive Value of Languages: Non-Linguistic Causes of Language , Push: Store an object in the stack; the workspace becomes empty. is accepted as being in the process of production; the stack must be empty at the final state. in the stack to combine with an elemental or combined object in the workspace. Merge DataFrame or named Series objects with a database-style join. The join is done on columns or indexes. If joining columns on columns, the DataFrame indexes will be ignored. Otherwise if joining indexes on indexes or indexes on a column or columns, the index will be passed on. Parameters right DataFrame or named Series. Object to merge with.

C++ and Object-Oriented Numeric Computing for Scientists and Engineers, Two sorted lists x and y can be merged by calling x.merge(y), Then x will hold the For example, list<double> ft; //an empty list list<double> sd; //an empty list If x or y is not sorted, it still produces a list containing the union of elements in x  I have two data.frames, one with only characters and the other one with characters and values. I want to merge df1 and df2. The characters a, b and c merged good and also have 0, 1, 0 but d and e has nothing. I want d and e also in the merge table, with the 0 0 condition. Thus for every missing row at the df2 data.frame, the 0 must be placed in