Calculates the matrix product of two matrices and writes output to the server-side.

ds.matrixMult(M1 = NULL, M2 = NULL, newobj = NULL, datasources = NULL)

Arguments

M1

a character string specifying the name of the first matrix.

M2

a character string specifying the name of the second matrix.

newobj

a character string that provides the name for the output variable that is stored on the data servers. Default matrixmult.newobj.

datasources

a list of DSConnection-class objects obtained after login. If the datasources argument is not specified the default set of connections will be used: see datashield.connections_default.

Value

ds.matrixMult returns to the server-side the result of the two matrix multiplication. Also, two validity messages are returned to the client-side indicating whether the new object has been created in each data source and if so whether it is in a valid form.

Details

Undertakes standard matrix multiplication wherewith input matrices A and B with dimensions A: m x n and B: n x p the output matrix C has dimensions m x p. This calculation is only valid if the number of columns of A is the same as the number of rows of B.

Server function called: matrixMultDS

Author

DataSHIELD Development Team

Examples

if (FALSE) { # \dontrun{

 ## Version 6, for version 5 see the Wiki
  
  # connecting to the Opal servers

  require('DSI')
  require('DSOpal')
  require('dsBaseClient')

  builder <- DSI::newDSLoginBuilder()
  builder$append(server = "study1", 
                 url = "http://192.168.56.100:8080/", 
                 user = "administrator", password = "datashield_test&", 
                 table = "CNSIM.CNSIM1", driver = "OpalDriver")
  builder$append(server = "study2", 
                 url = "http://192.168.56.100:8080/", 
                 user = "administrator", password = "datashield_test&", 
                 table = "CNSIM.CNSIM2", driver = "OpalDriver")
  builder$append(server = "study3",
                 url = "http://192.168.56.100:8080/", 
                 user = "administrator", password = "datashield_test&", 
                 table = "CNSIM.CNSIM3", driver = "OpalDriver")
  logindata <- builder$build()
  
  connections <- DSI::datashield.login(logins = logindata, assign = TRUE, symbol = "D") 
  
            
  #Example 1: Multiplicate two server-side matrix
  
  #Create the server-side vector 
  
  ds.rUnif(samp.size = 9,
           min = -10.5,
           max = 10.5,
           newobj = "ss.vector.9",
           seed.as.integer = 5575,
           force.output.to.k.decimal.places = 0,
           datasources = connections)
           
  #Create the server-side matrixes
           
  ds.matrix(mdata = "ss.vector.9",#using the created vector
            from = "serverside.vector",
            nrows.scalar = 5,
            ncols.scalar = 4,
            byrow = TRUE,
            newobj = "matrix1",
            datasources = connections)
            
   ds.matrix(mdata = 10,
             from = "clientside.scalar",
             nrows.scalar = 4,
             ncols.scalar = 6,
             byrow = TRUE,
             newobj = "matrix2",
             datasources = connections)

  #Multiplicate the matrixes
  
  ds.matrixMult(M1 = "matrix1", 
                M2 = "matrix2", 
                newobj = "matrix.mult", 
                datasources = connections)
  
  # clear the Datashield R sessions and logout
  datashield.logout(connections)
} # }