# difference_byname: Name-wise subtraction of matrices In matsbyname: An Implementation of Matrix Mathematics

 difference_byname R Documentation

## Name-wise subtraction of matrices

### Description

Name-wise subtraction of matrices

### Usage

```difference_byname(minuend, subtrahend)
```

### Arguments

 `minuend` matrix or constant `subtrahend` matrix or constant Performs a union and sorting of row and column names prior to differencing. Zeroes are inserted for missing matrix elements.

### Value

A matrix representing the name-wise difference between `minuend` and `subtrahend`

### Examples

```library(dplyr)
difference_byname(100, 50)
commoditynames <- c("c1", "c2")
industrynames <- c("i1", "i2")
U <- matrix(1:4, ncol = 2, dimnames = list(commoditynames, industrynames)) %>%
setrowtype("Commodities") %>% setcoltype("Industries")
G <- matrix(rev(1:4), ncol = 2, dimnames = list(rev(commoditynames), rev(industrynames))) %>%
setrowtype("Commodities") %>% setcoltype("Industries")
U - G # Non-sensical. Row and column names not respected.
difference_byname(U, G) # Row and column names respected! Should be all zeroes.
difference_byname(100, U)
difference_byname(10, G)
difference_byname(G) # When subtrahend is missing, return minuend (in this case, G).
difference_byname(subtrahend = G) # When minuend is missing, return - subtrahend (in this case, -G)
# This also works with lists
difference_byname(list(100, 100), list(50, 50))
difference_byname(list(U,U), list(G,G))
DF <- data.frame(U = I(list()), G = I(list()))
DF[[1,"U"]] <- U
DF[[2,"U"]] <- U
DF[[1,"G"]] <- G
DF[[2,"G"]] <- G
difference_byname(DF\$U, DF\$G)
DF %>% mutate(diffs = difference_byname(U, G))
```

matsbyname documentation built on April 2, 2022, 1:06 a.m.